ACLOCAL_AMFLAGS = -I config
-SUBDIRS = liblttng-sessiond-comm \
+SUBDIRS = common \
+ liblttng-sessiond-comm \
libkernelctl \
librunas \
liblttng-kconsumer \
--- /dev/null
+/*
+ * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; only version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <urcu.h>
+
+#include <lttng-share.h>
+
+#include "hashtable.h"
+#include "hashtable/rculfhash.h"
+#include "hashtable/hash.h"
+
+struct cds_lfht *hashtable_new(unsigned long size)
+{
+ if (size == 0) {
+ size = DEFAULT_HT_SIZE;
+ }
+
+ return cds_lfht_new(hash_key, hash_compare_key, 0x42UL,
+ size, size, CDS_LFHT_AUTO_RESIZE, NULL);
+}
+
+struct cds_lfht *hashtable_new_str(unsigned long size)
+{
+ if (size == 0) {
+ size = DEFAULT_HT_SIZE;
+ }
+
+ return cds_lfht_new(hash_key_str, hash_compare_key_str, 0x42UL,
+ size, size, CDS_LFHT_AUTO_RESIZE, NULL);
+}
+
+struct cds_lfht_node *hashtable_iter_get_node(struct cds_lfht_iter *iter)
+{
+ /* Safety net */
+ if (iter == NULL) {
+ return NULL;
+ }
+
+ return cds_lfht_iter_get_node(iter);
+}
+
+struct cds_lfht_node *hashtable_lookup(struct cds_lfht *ht, void *key,
+ size_t key_len, struct cds_lfht_iter *iter)
+{
+ /* Safety net */
+ if (ht == NULL || iter == NULL || key == NULL) {
+ return NULL;
+ }
+
+ cds_lfht_lookup(ht, key, key_len, iter);
+
+ return hashtable_iter_get_node(iter);
+}
+
+void hashtable_get_first(struct cds_lfht *ht, struct cds_lfht_iter *iter)
+{
+ cds_lfht_first(ht, iter);
+}
+
+void hashtable_get_next(struct cds_lfht *ht, struct cds_lfht_iter *iter)
+{
+ cds_lfht_next(ht, iter);
+}
+
+void hashtable_add_unique(struct cds_lfht *ht, struct cds_lfht_node *node)
+{
+ cds_lfht_add_unique(ht, node);
+}
+
+void hashtable_node_init(struct cds_lfht_node *node, void *key,
+ size_t key_len)
+{
+ cds_lfht_node_init(node, key, key_len);
+}
+
+int hashtable_del(struct cds_lfht *ht, struct cds_lfht_iter *iter)
+{
+ /* Safety net */
+ if (ht == NULL || iter == NULL) {
+ return -1;
+ }
+
+ return cds_lfht_del(ht, iter);
+}
+
+unsigned long hashtable_get_count(struct cds_lfht *ht)
+{
+ long ab, aa;
+ unsigned long count, removed;
+
+ cds_lfht_count_nodes(ht, &ab, &count, &removed, &aa);
+
+ return count;
+}
+
+int hashtable_destroy(struct cds_lfht *ht)
+{
+ return cds_lfht_destroy(ht, NULL);
+}
--- /dev/null
+/*
+ * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; only version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#ifndef _LTT_HASHTABLE_H
+#define _LTT_HASHTABLE_H
+
+#include <urcu.h>
+#include "hashtable/rculfhash.h"
+
+struct cds_lfht *hashtable_new(unsigned long size);
+struct cds_lfht *hashtable_new_str(unsigned long size);
+
+struct cds_lfht_node *hashtable_iter_get_node(struct cds_lfht_iter *iter);
+struct cds_lfht_node *hashtable_lookup(struct cds_lfht *ht, void *key,
+ size_t key_len, struct cds_lfht_iter *iter);
+
+void hashtable_get_first(struct cds_lfht *ht, struct cds_lfht_iter *iter);
+void hashtable_get_next(struct cds_lfht *ht, struct cds_lfht_iter *iter);
+void hashtable_add_unique(struct cds_lfht *ht, struct cds_lfht_node *node);
+void hashtable_node_init(struct cds_lfht_node *node,
+ void *key, size_t key_len);
+
+int hashtable_del(struct cds_lfht *ht, struct cds_lfht_iter *iter);
+unsigned long hashtable_get_count(struct cds_lfht *ht);
+int hashtable_destroy(struct cds_lfht *ht);
+
+#endif /* _LTT_HASHTABLE_H */
--- /dev/null
+/*
+ * Copyright (C) - Bob Jenkins, May 2006, Public Domain.
+ * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
+ * Copyright (C) 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * These are functions for producing 32-bit hashes for hash table lookup.
+ * hashword(), hashlittle(), hashlittle2(), hashbig(), mix(), and final() are
+ * externally useful functions. Routines to test the hash are included if
+ * SELF_TEST is defined. You can use this free for any purpose. It's in the
+ * public domain. It has no warranty.
+ *
+ * You probably want to use hashlittle(). hashlittle() and hashbig() hash byte
+ * arrays. hashlittle() is is faster than hashbig() on little-endian machines.
+ * Intel and AMD are little-endian machines. On second thought, you probably
+ * want hashlittle2(), which is identical to hashlittle() except it returns two
+ * 32-bit hashes for the price of one. You could implement hashbig2() if you
+ * wanted but I haven't bothered here.
+ *
+ * If you want to find a hash of, say, exactly 7 integers, do
+ * a = i1; b = i2; c = i3;
+ * mix(a,b,c);
+ * a += i4; b += i5; c += i6;
+ * mix(a,b,c);
+ * a += i7;
+ * final(a,b,c);
+ * then use c as the hash value. If you have a variable length array of
+ * 4-byte integers to hash, use hashword(). If you have a byte array (like
+ * a character string), use hashlittle(). If you have several byte arrays, or
+ * a mix of things, see the comments above hashlittle().
+ *
+ * Why is this so big? I read 12 bytes at a time into 3 4-byte integers, then
+ * mix those integers. This is fast (you can do a lot more thorough mixing
+ * with 12*3 instructions on 3 integers than you can with 3 instructions on 1
+ * byte), but shoehorning those bytes into integers efficiently is messy.
+ */
+
+#include <stdio.h> /* defines printf for tests */
+#include <time.h> /* defines time_t for timings in the test */
+#include <stdint.h> /* defines uint32_t etc */
+#include <sys/param.h> /* attempt to define endianness */
+#include <endian.h> /* attempt to define endianness */
+#include <string.h>
+#include <assert.h>
+#include <urcu/compiler.h>
+
+/*
+ * My best guess at if you are big-endian or little-endian. This may
+ * need adjustment.
+ */
+#if (defined(__BYTE_ORDER) && defined(__LITTLE_ENDIAN) && \
+ __BYTE_ORDER == __LITTLE_ENDIAN) || \
+ (defined(i386) || defined(__i386__) || defined(__i486__) || \
+ defined(__i586__) || defined(__i686__) || defined(vax) || defined(MIPSEL))
+# define HASH_LITTLE_ENDIAN 1
+# define HASH_BIG_ENDIAN 0
+#elif (defined(__BYTE_ORDER) && defined(__BIG_ENDIAN) && \
+ __BYTE_ORDER == __BIG_ENDIAN) || \
+ (defined(sparc) || defined(POWERPC) || defined(mc68000) || defined(sel))
+# define HASH_LITTLE_ENDIAN 0
+# define HASH_BIG_ENDIAN 1
+#else
+# define HASH_LITTLE_ENDIAN 0
+# define HASH_BIG_ENDIAN 0
+#endif
+
+#define hashsize(n) ((uint32_t)1<<(n))
+#define hashmask(n) (hashsize(n)-1)
+#define rot(x,k) (((x)<<(k)) | ((x)>>(32-(k))))
+
+/*
+ * mix -- mix 3 32-bit values reversibly.
+ *
+ * This is reversible, so any information in (a,b,c) before mix() is
+ * still in (a,b,c) after mix().
+ *
+ * If four pairs of (a,b,c) inputs are run through mix(), or through
+ * mix() in reverse, there are at least 32 bits of the output that
+ * are sometimes the same for one pair and different for another pair.
+ * This was tested for:
+ * * pairs that differed by one bit, by two bits, in any combination
+ * of top bits of (a,b,c), or in any combination of bottom bits of
+ * (a,b,c).
+ * * "differ" is defined as +, -, ^, or ~^. For + and -, I transformed
+ * the output delta to a Gray code (a^(a>>1)) so a string of 1's (as
+ * is commonly produced by subtraction) look like a single 1-bit
+ * difference.
+ * * the base values were pseudorandom, all zero but one bit set, or
+ * all zero plus a counter that starts at zero.
+ *
+ * Some k values for my "a-=c; a^=rot(c,k); c+=b;" arrangement that
+ * satisfy this are
+ * 4 6 8 16 19 4
+ * 9 15 3 18 27 15
+ * 14 9 3 7 17 3
+ * Well, "9 15 3 18 27 15" didn't quite get 32 bits diffing
+ * for "differ" defined as + with a one-bit base and a two-bit delta. I
+ * used http://burtleburtle.net/bob/hash/avalanche.html to choose
+ * the operations, constants, and arrangements of the variables.
+ *
+ * This does not achieve avalanche. There are input bits of (a,b,c)
+ * that fail to affect some output bits of (a,b,c), especially of a. The
+ * most thoroughly mixed value is c, but it doesn't really even achieve
+ * avalanche in c.
+ *
+ * This allows some parallelism. Read-after-writes are good at doubling
+ * the number of bits affected, so the goal of mixing pulls in the opposite
+ * direction as the goal of parallelism. I did what I could. Rotates
+ * seem to cost as much as shifts on every machine I could lay my hands
+ * on, and rotates are much kinder to the top and bottom bits, so I used
+ * rotates.
+ */
+#define mix(a,b,c) \
+{ \
+ a -= c; a ^= rot(c, 4); c += b; \
+ b -= a; b ^= rot(a, 6); a += c; \
+ c -= b; c ^= rot(b, 8); b += a; \
+ a -= c; a ^= rot(c,16); c += b; \
+ b -= a; b ^= rot(a,19); a += c; \
+ c -= b; c ^= rot(b, 4); b += a; \
+}
+
+/*
+ * final -- final mixing of 3 32-bit values (a,b,c) into c
+ *
+ * Pairs of (a,b,c) values differing in only a few bits will usually
+ * produce values of c that look totally different. This was tested for
+ * * pairs that differed by one bit, by two bits, in any combination
+ * of top bits of (a,b,c), or in any combination of bottom bits of
+ * (a,b,c).
+ * * "differ" is defined as +, -, ^, or ~^. For + and -, I transformed
+ * the output delta to a Gray code (a^(a>>1)) so a string of 1's (as
+ * is commonly produced by subtraction) look like a single 1-bit
+ * difference.
+ * * the base values were pseudorandom, all zero but one bit set, or
+ * all zero plus a counter that starts at zero.
+ *
+ * These constants passed:
+ * 14 11 25 16 4 14 24
+ * 12 14 25 16 4 14 24
+ * and these came close:
+ * 4 8 15 26 3 22 24
+ * 10 8 15 26 3 22 24
+ * 11 8 15 26 3 22 24
+ */
+#define final(a,b,c) \
+{ \
+ c ^= b; c -= rot(b,14); \
+ a ^= c; a -= rot(c,11); \
+ b ^= a; b -= rot(a,25); \
+ c ^= b; c -= rot(b,16); \
+ a ^= c; a -= rot(c,4); \
+ b ^= a; b -= rot(a,14); \
+ c ^= b; c -= rot(b,24); \
+}
+
+static __attribute__((unused))
+uint32_t hashword(
+ const uint32_t *k, /* the key, an array of uint32_t values */
+ size_t length, /* the length of the key, in uint32_ts */
+ uint32_t initval) /* the previous hash, or an arbitrary value */
+{
+ uint32_t a, b, c;
+
+ /* Set up the internal state */
+ a = b = c = 0xdeadbeef + (((uint32_t) length) << 2) + initval;
+
+ /*----------------------------------------- handle most of the key */
+ while (length > 3) {
+ a += k[0];
+ b += k[1];
+ c += k[2];
+ mix(a, b, c);
+ length -= 3;
+ k += 3;
+ }
+
+ /*----------------------------------- handle the last 3 uint32_t's */
+ switch (length) { /* all the case statements fall through */
+ case 3: c += k[2];
+ case 2: b += k[1];
+ case 1: a += k[0];
+ final(a, b, c);
+ case 0: /* case 0: nothing left to add */
+ break;
+ }
+ /*---------------------------------------------- report the result */
+ return c;
+}
+
+
+/*
+ * hashword2() -- same as hashword(), but take two seeds and return two 32-bit
+ * values. pc and pb must both be nonnull, and *pc and *pb must both be
+ * initialized with seeds. If you pass in (*pb)==0, the output (*pc) will be
+ * the same as the return value from hashword().
+ */
+static __attribute__((unused))
+void hashword2(const uint32_t *k, size_t length,
+ uint32_t *pc, uint32_t *pb)
+{
+ uint32_t a, b, c;
+
+ /* Set up the internal state */
+ a = b = c = 0xdeadbeef + ((uint32_t) (length << 2)) + *pc;
+ c += *pb;
+
+ while (length > 3) {
+ a += k[0];
+ b += k[1];
+ c += k[2];
+ mix(a, b, c);
+ length -= 3;
+ k += 3;
+ }
+
+ switch (length) {
+ case 3 :
+ c += k[2];
+ case 2 :
+ b += k[1];
+ case 1 :
+ a += k[0];
+ final(a, b, c);
+ case 0: /* case 0: nothing left to add */
+ break;
+ }
+
+ *pc = c;
+ *pb = b;
+}
+
+/*
+ * hashlittle() -- hash a variable-length key into a 32-bit value
+ * k : the key (the unaligned variable-length array of bytes)
+ * length : the length of the key, counting by bytes
+ * initval : can be any 4-byte value
+ * Returns a 32-bit value. Every bit of the key affects every bit of
+ * the return value. Two keys differing by one or two bits will have
+ * totally different hash values.
+ *
+ * The best hash table sizes are powers of 2. There is no need to do
+ * mod a prime (mod is sooo slow!). If you need less than 32 bits,
+ * use a bitmask. For example, if you need only 10 bits, do
+ * h = (h & hashmask(10));
+ * In which case, the hash table should have hashsize(10) elements.
+ *
+ * If you are hashing n strings (uint8_t **)k, do it like this:
+ * for (i=0, h=0; i<n; ++i) h = hashlittle( k[i], len[i], h);
+ *
+ * By Bob Jenkins, 2006. bob_jenkins@burtleburtle.net. You may use this
+ * code any way you wish, private, educational, or commercial. It's free.
+ *
+ * Use for hash table lookup, or anything where one collision in 2^^32 is
+ * acceptable. Do NOT use for cryptographic purposes.
+ */
+
+static uint32_t hashlittle(const void *key, size_t length, uint32_t initval)
+{
+ uint32_t a,b,c;
+ union {
+ const void *ptr;
+ size_t i;
+ } u; /* needed for Mac Powerbook G4 */
+
+ /* Set up the internal state */
+ a = b = c = 0xdeadbeef + ((uint32_t)length) + initval;
+
+ u.ptr = key;
+ if (HASH_LITTLE_ENDIAN && ((u.i & 0x3) == 0)) {
+ const uint32_t *k = (const uint32_t *)key; /* read 32-bit chunks */
+
+ /*------ all but last block: aligned reads and affect 32 bits of (a,b,c) */
+ while (length > 12) {
+ a += k[0];
+ b += k[1];
+ c += k[2];
+ mix(a,b,c);
+ length -= 12;
+ k += 3;
+ }
+
+ /*
+ * "k[2]&0xffffff" actually reads beyond the end of the string, but
+ * then masks off the part it's not allowed to read. Because the
+ * string is aligned, the masked-off tail is in the same word as the
+ * rest of the string. Every machine with memory protection I've seen
+ * does it on word boundaries, so is OK with this. But VALGRIND will
+ * still catch it and complain. The masking trick does make the hash
+ * noticably faster for short strings (like English words).
+ */
+#ifndef VALGRIND
+
+ switch (length) {
+ case 12: c+=k[2]; b+=k[1]; a+=k[0]; break;
+ case 11: c+=k[2]&0xffffff; b+=k[1]; a+=k[0]; break;
+ case 10: c+=k[2]&0xffff; b+=k[1]; a+=k[0]; break;
+ case 9 : c+=k[2]&0xff; b+=k[1]; a+=k[0]; break;
+ case 8 : b+=k[1]; a+=k[0]; break;
+ case 7 : b+=k[1]&0xffffff; a+=k[0]; break;
+ case 6 : b+=k[1]&0xffff; a+=k[0]; break;
+ case 5 : b+=k[1]&0xff; a+=k[0]; break;
+ case 4 : a+=k[0]; break;
+ case 3 : a+=k[0]&0xffffff; break;
+ case 2 : a+=k[0]&0xffff; break;
+ case 1 : a+=k[0]&0xff; break;
+ case 0 : return c; /* zero length strings require no mixing */
+ }
+#else /* make valgrind happy */
+ const uint8_t *k8;
+
+ k8 = (const uint8_t *)k;
+ switch (length) {
+ case 12: c+=k[2]; b+=k[1]; a+=k[0]; break;
+ case 11: c+=((uint32_t)k8[10])<<16; /* fall through */
+ case 10: c+=((uint32_t)k8[9])<<8; /* fall through */
+ case 9 : c+=k8[8]; /* fall through */
+ case 8 : b+=k[1]; a+=k[0]; break;
+ case 7 : b+=((uint32_t)k8[6])<<16; /* fall through */
+ case 6 : b+=((uint32_t)k8[5])<<8; /* fall through */
+ case 5 : b+=k8[4]; /* fall through */
+ case 4 : a+=k[0]; break;
+ case 3 : a+=((uint32_t)k8[2])<<16; /* fall through */
+ case 2 : a+=((uint32_t)k8[1])<<8; /* fall through */
+ case 1 : a+=k8[0]; break;
+ case 0 : return c;
+ }
+#endif /* !valgrind */
+ } else if (HASH_LITTLE_ENDIAN && ((u.i & 0x1) == 0)) {
+ const uint16_t *k = (const uint16_t *)key; /* read 16-bit chunks */
+ const uint8_t *k8;
+
+ /*--------------- all but last block: aligned reads and different mixing */
+ while (length > 12) {
+ a += k[0] + (((uint32_t)k[1])<<16);
+ b += k[2] + (((uint32_t)k[3])<<16);
+ c += k[4] + (((uint32_t)k[5])<<16);
+ mix(a,b,c);
+ length -= 12;
+ k += 6;
+ }
+
+ k8 = (const uint8_t *)k;
+ switch (length) {
+ case 12:
+ c+=k[4]+(((uint32_t)k[5])<<16);
+ b+=k[2]+(((uint32_t)k[3])<<16);
+ a+=k[0]+(((uint32_t)k[1])<<16);
+ break;
+ case 11:
+ c+=((uint32_t)k8[10])<<16; /* fall through */
+ case 10:
+ c+=k[4];
+ b+=k[2]+(((uint32_t)k[3])<<16);
+ a+=k[0]+(((uint32_t)k[1])<<16);
+ break;
+ case 9:
+ c+=k8[8]; /* fall through */
+ case 8:
+ b+=k[2]+(((uint32_t)k[3])<<16);
+ a+=k[0]+(((uint32_t)k[1])<<16);
+ break;
+ case 7:
+ b+=((uint32_t)k8[6])<<16; /* fall through */
+ case 6:
+ b+=k[2];
+ a+=k[0]+(((uint32_t)k[1])<<16);
+ break;
+ case 5:
+ b+=k8[4]; /* fall through */
+ case 4:
+ a+=k[0]+(((uint32_t)k[1])<<16);
+ break;
+ case 3:
+ a+=((uint32_t)k8[2])<<16; /* fall through */
+ case 2:
+ a+=k[0];
+ break;
+ case 1:
+ a+=k8[0];
+ break;
+ case 0:
+ return c; /* zero length requires no mixing */
+ }
+
+ } else { /* need to read the key one byte at a time */
+ const uint8_t *k = (const uint8_t *)key;
+
+ while (length > 12) {
+ a += k[0];
+ a += ((uint32_t)k[1])<<8;
+ a += ((uint32_t)k[2])<<16;
+ a += ((uint32_t)k[3])<<24;
+ b += k[4];
+ b += ((uint32_t)k[5])<<8;
+ b += ((uint32_t)k[6])<<16;
+ b += ((uint32_t)k[7])<<24;
+ c += k[8];
+ c += ((uint32_t)k[9])<<8;
+ c += ((uint32_t)k[10])<<16;
+ c += ((uint32_t)k[11])<<24;
+ mix(a,b,c);
+ length -= 12;
+ k += 12;
+ }
+
+ switch(length) { /* all the case statements fall through */
+ case 12: c+=((uint32_t)k[11])<<24;
+ case 11: c+=((uint32_t)k[10])<<16;
+ case 10: c+=((uint32_t)k[9])<<8;
+ case 9: c+=k[8];
+ case 8: b+=((uint32_t)k[7])<<24;
+ case 7: b+=((uint32_t)k[6])<<16;
+ case 6: b+=((uint32_t)k[5])<<8;
+ case 5: b+=k[4];
+ case 4: a+=((uint32_t)k[3])<<24;
+ case 3: a+=((uint32_t)k[2])<<16;
+ case 2: a+=((uint32_t)k[1])<<8;
+ case 1:
+ a+=k[0];
+ break;
+ case 0:
+ return c;
+ }
+ }
+
+ final(a,b,c);
+ return c;
+}
+
+#if (CAA_BITS_PER_LONG == 64)
+/*
+ * Hash function for number value.
+ */
+unsigned long hash_key(void *_key, size_t length, unsigned long seed)
+{
+ union {
+ uint64_t v64;
+ uint32_t v32[2];
+ } v;
+ union {
+ uint64_t v64;
+ uint32_t v32[2];
+ } key;
+
+ assert(length == sizeof(unsigned long));
+ v.v64 = (uint64_t) seed;
+ key.v64 = (uint64_t) _key;
+ hashword2(key.v32, 2, &v.v32[0], &v.v32[1]);
+ return v.v64;
+}
+#else
+/*
+ * Hash function for number value.
+ */
+unsigned long hash_key(void *_key, size_t length, unsigned long seed)
+{
+ uint32_t key = (uint32_t) _key;
+
+ assert(length == sizeof(uint32_t));
+ return hashword(&key, 1, seed);
+}
+#endif
+
+/*
+ * Hash function for string.
+ */
+unsigned long hash_key_str(void *key, size_t length, unsigned long seed)
+{
+ return hashlittle(key, length, seed);
+}
+
+/*
+ * Hash function compare for number value.
+ */
+unsigned long hash_compare_key(void *key1, size_t key1_len,
+ void *key2, size_t key2_len)
+{
+ if (key1_len != key2_len) {
+ return -1;
+ }
+
+ if (key1 == key2) {
+ return 0;
+ }
+
+ return 1;
+}
+
+/*
+ * Hash compare function for string.
+ */
+unsigned long hash_compare_key_str(void *key1, size_t key1_len,
+ void *key2, size_t key2_len)
+{
+ if (key1_len != key2_len) {
+ return -1;
+ }
+
+ if (strncmp(key1, key2, key1_len) == 0) {
+ return 0;
+ }
+
+ return 1;
+}
--- /dev/null
+/*
+ * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; only version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#ifndef _LTT_HASH_H
+#define _LTT_HASH_H
+
+unsigned long hash_key(void *_key, size_t length, unsigned long seed);
+
+unsigned long hash_key_str(void *_key, size_t length, unsigned long seed);
+
+unsigned long hash_compare_key(void *key1, size_t key1_len,
+ void *key2, size_t key2_len);
+
+unsigned long hash_compare_key_str(void *key1, size_t key1_len,
+ void *key2, size_t key2_len);
+
+#endif /* _LTT_HASH_H */
--- /dev/null
+/*
+ * rculfhash.c
+ *
+ * Userspace RCU library - Lock-Free Resizable RCU Hash Table
+ *
+ * Copyright 2010-2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/*
+ * Based on the following articles:
+ * - Ori Shalev and Nir Shavit. Split-ordered lists: Lock-free
+ * extensible hash tables. J. ACM 53, 3 (May 2006), 379-405.
+ * - Michael, M. M. High performance dynamic lock-free hash tables
+ * and list-based sets. In Proceedings of the fourteenth annual ACM
+ * symposium on Parallel algorithms and architectures, ACM Press,
+ * (2002), 73-82.
+ *
+ * Some specificities of this Lock-Free Resizable RCU Hash Table
+ * implementation:
+ *
+ * - RCU read-side critical section allows readers to perform hash
+ * table lookups and use the returned objects safely by delaying
+ * memory reclaim of a grace period.
+ * - Add and remove operations are lock-free, and do not need to
+ * allocate memory. They need to be executed within RCU read-side
+ * critical section to ensure the objects they read are valid and to
+ * deal with the cmpxchg ABA problem.
+ * - add and add_unique operations are supported. add_unique checks if
+ * the node key already exists in the hash table. It ensures no key
+ * duplicata exists.
+ * - The resize operation executes concurrently with add/remove/lookup.
+ * - Hash table nodes are contained within a split-ordered list. This
+ * list is ordered by incrementing reversed-bits-hash value.
+ * - An index of dummy nodes is kept. These dummy nodes are the hash
+ * table "buckets", and they are also chained together in the
+ * split-ordered list, which allows recursive expansion.
+ * - The resize operation for small tables only allows expanding the hash table.
+ * It is triggered automatically by detecting long chains in the add
+ * operation.
+ * - The resize operation for larger tables (and available through an
+ * API) allows both expanding and shrinking the hash table.
+ * - Split-counters are used to keep track of the number of
+ * nodes within the hash table for automatic resize triggering.
+ * - Resize operation initiated by long chain detection is executed by a
+ * call_rcu thread, which keeps lock-freedom of add and remove.
+ * - Resize operations are protected by a mutex.
+ * - The removal operation is split in two parts: first, a "removed"
+ * flag is set in the next pointer within the node to remove. Then,
+ * a "garbage collection" is performed in the bucket containing the
+ * removed node (from the start of the bucket up to the removed node).
+ * All encountered nodes with "removed" flag set in their next
+ * pointers are removed from the linked-list. If the cmpxchg used for
+ * removal fails (due to concurrent garbage-collection or concurrent
+ * add), we retry from the beginning of the bucket. This ensures that
+ * the node with "removed" flag set is removed from the hash table
+ * (not visible to lookups anymore) before the RCU read-side critical
+ * section held across removal ends. Furthermore, this ensures that
+ * the node with "removed" flag set is removed from the linked-list
+ * before its memory is reclaimed. Only the thread which removal
+ * successfully set the "removed" flag (with a cmpxchg) into a node's
+ * next pointer is considered to have succeeded its removal (and thus
+ * owns the node to reclaim). Because we garbage-collect starting from
+ * an invariant node (the start-of-bucket dummy node) up to the
+ * "removed" node (or find a reverse-hash that is higher), we are sure
+ * that a successful traversal of the chain leads to a chain that is
+ * present in the linked-list (the start node is never removed) and
+ * that is does not contain the "removed" node anymore, even if
+ * concurrent delete/add operations are changing the structure of the
+ * list concurrently.
+ * - The add operation performs gargage collection of buckets if it
+ * encounters nodes with removed flag set in the bucket where it wants
+ * to add its new node. This ensures lock-freedom of add operation by
+ * helping the remover unlink nodes from the list rather than to wait
+ * for it do to so.
+ * - A RCU "order table" indexed by log2(hash index) is copied and
+ * expanded by the resize operation. This order table allows finding
+ * the "dummy node" tables.
+ * - There is one dummy node table per hash index order. The size of
+ * each dummy node table is half the number of hashes contained in
+ * this order (except for order 0).
+ * - synchronzie_rcu is used to garbage-collect the old dummy node table.
+ * - The per-order dummy node tables contain a compact version of the
+ * hash table nodes. These tables are invariant after they are
+ * populated into the hash table.
+ *
+ * Dummy node tables:
+ *
+ * hash table hash table the last all dummy node tables
+ * order size dummy node 0 1 2 3 4 5 6(index)
+ * table size
+ * 0 1 1 1
+ * 1 2 1 1 1
+ * 2 4 2 1 1 2
+ * 3 8 4 1 1 2 4
+ * 4 16 8 1 1 2 4 8
+ * 5 32 16 1 1 2 4 8 16
+ * 6 64 32 1 1 2 4 8 16 32
+ *
+ * When growing/shrinking, we only focus on the last dummy node table
+ * which size is (!order ? 1 : (1 << (order -1))).
+ *
+ * Example for growing/shrinking:
+ * grow hash table from order 5 to 6: init the index=6 dummy node table
+ * shrink hash table from order 6 to 5: fini the index=6 dummy node table
+ *
+ * A bit of ascii art explanation:
+ *
+ * Order index is the off-by-one compare to the actual power of 2 because
+ * we use index 0 to deal with the 0 special-case.
+ *
+ * This shows the nodes for a small table ordered by reversed bits:
+ *
+ * bits reverse
+ * 0 000 000
+ * 4 100 001
+ * 2 010 010
+ * 6 110 011
+ * 1 001 100
+ * 5 101 101
+ * 3 011 110
+ * 7 111 111
+ *
+ * This shows the nodes in order of non-reversed bits, linked by
+ * reversed-bit order.
+ *
+ * order bits reverse
+ * 0 0 000 000
+ * 1 | 1 001 100 <-
+ * 2 | | 2 010 010 <- |
+ * | | | 3 011 110 | <- |
+ * 3 -> | | | 4 100 001 | |
+ * -> | | 5 101 101 |
+ * -> | 6 110 011
+ * -> 7 111 111
+ */
+
+#define _LGPL_SOURCE
+#include <stdlib.h>
+#include <errno.h>
+#include <assert.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+
+#include "config.h"
+#include <urcu.h>
+#include <urcu-call-rcu.h>
+#include <urcu/arch.h>
+#include <urcu/uatomic.h>
+#include <urcu/compiler.h>
+#include <stdio.h>
+#include <pthread.h>
+
+#include "rculfhash.h"
+
+#ifdef DEBUG
+#define dbg_printf(fmt, args...) printf("[debug rculfhash] " fmt, ## args)
+#else
+#define dbg_printf(fmt, args...)
+#endif
+
+/*
+ * Split-counters lazily update the global counter each 1024
+ * addition/removal. It automatically keeps track of resize required.
+ * We use the bucket length as indicator for need to expand for small
+ * tables and machines lacking per-cpu data suppport.
+ */
+#define COUNT_COMMIT_ORDER 10
+#define DEFAULT_SPLIT_COUNT_MASK 0xFUL
+#define CHAIN_LEN_TARGET 1
+#define CHAIN_LEN_RESIZE_THRESHOLD 3
+
+/*
+ * Define the minimum table size.
+ */
+#define MIN_TABLE_SIZE 1
+
+#if (CAA_BITS_PER_LONG == 32)
+#define MAX_TABLE_ORDER 32
+#else
+#define MAX_TABLE_ORDER 64
+#endif
+
+/*
+ * Minimum number of dummy nodes to touch per thread to parallelize grow/shrink.
+ */
+#define MIN_PARTITION_PER_THREAD_ORDER 12
+#define MIN_PARTITION_PER_THREAD (1UL << MIN_PARTITION_PER_THREAD_ORDER)
+
+#ifndef min
+#define min(a, b) ((a) < (b) ? (a) : (b))
+#endif
+
+#ifndef max
+#define max(a, b) ((a) > (b) ? (a) : (b))
+#endif
+
+/*
+ * The removed flag needs to be updated atomically with the pointer.
+ * It indicates that no node must attach to the node scheduled for
+ * removal, and that node garbage collection must be performed.
+ * The dummy flag does not require to be updated atomically with the
+ * pointer, but it is added as a pointer low bit flag to save space.
+ */
+#define REMOVED_FLAG (1UL << 0)
+#define DUMMY_FLAG (1UL << 1)
+#define FLAGS_MASK ((1UL << 2) - 1)
+
+/* Value of the end pointer. Should not interact with flags. */
+#define END_VALUE NULL
+
+/*
+ * ht_items_count: Split-counters counting the number of node addition
+ * and removal in the table. Only used if the CDS_LFHT_ACCOUNTING flag
+ * is set at hash table creation.
+ *
+ * These are free-running counters, never reset to zero. They count the
+ * number of add/remove, and trigger every (1 << COUNT_COMMIT_ORDER)
+ * operations to update the global counter. We choose a power-of-2 value
+ * for the trigger to deal with 32 or 64-bit overflow of the counter.
+ */
+struct ht_items_count {
+ unsigned long add, del;
+} __attribute__((aligned(CAA_CACHE_LINE_SIZE)));
+
+/*
+ * rcu_level: Contains the per order-index-level dummy node table. The
+ * size of each dummy node table is half the number of hashes contained
+ * in this order (except for order 0). The minimum allocation size
+ * parameter allows combining the dummy node arrays of the lowermost
+ * levels to improve cache locality for small index orders.
+ */
+struct rcu_level {
+ /* Note: manually update allocation length when adding a field */
+ struct _cds_lfht_node nodes[0];
+};
+
+/*
+ * rcu_table: Contains the size and desired new size if a resize
+ * operation is in progress, as well as the statically-sized array of
+ * rcu_level pointers.
+ */
+struct rcu_table {
+ unsigned long size; /* always a power of 2, shared (RCU) */
+ unsigned long resize_target;
+ int resize_initiated;
+ struct rcu_level *tbl[MAX_TABLE_ORDER];
+};
+
+/*
+ * cds_lfht: Top-level data structure representing a lock-free hash
+ * table. Defined in the implementation file to make it be an opaque
+ * cookie to users.
+ */
+struct cds_lfht {
+ struct rcu_table t;
+ cds_lfht_hash_fct hash_fct;
+ cds_lfht_compare_fct compare_fct;
+ unsigned long min_alloc_order;
+ unsigned long min_alloc_size;
+ unsigned long hash_seed;
+ int flags;
+ /*
+ * We need to put the work threads offline (QSBR) when taking this
+ * mutex, because we use synchronize_rcu within this mutex critical
+ * section, which waits on read-side critical sections, and could
+ * therefore cause grace-period deadlock if we hold off RCU G.P.
+ * completion.
+ */
+ pthread_mutex_t resize_mutex; /* resize mutex: add/del mutex */
+ unsigned int in_progress_resize, in_progress_destroy;
+ void (*cds_lfht_call_rcu)(struct rcu_head *head,
+ void (*func)(struct rcu_head *head));
+ void (*cds_lfht_synchronize_rcu)(void);
+ void (*cds_lfht_rcu_read_lock)(void);
+ void (*cds_lfht_rcu_read_unlock)(void);
+ void (*cds_lfht_rcu_thread_offline)(void);
+ void (*cds_lfht_rcu_thread_online)(void);
+ void (*cds_lfht_rcu_register_thread)(void);
+ void (*cds_lfht_rcu_unregister_thread)(void);
+ pthread_attr_t *resize_attr; /* Resize threads attributes */
+ long count; /* global approximate item count */
+ struct ht_items_count *split_count; /* split item count */
+};
+
+/*
+ * rcu_resize_work: Contains arguments passed to RCU worker thread
+ * responsible for performing lazy resize.
+ */
+struct rcu_resize_work {
+ struct rcu_head head;
+ struct cds_lfht *ht;
+};
+
+/*
+ * partition_resize_work: Contains arguments passed to worker threads
+ * executing the hash table resize on partitions of the hash table
+ * assigned to each processor's worker thread.
+ */
+struct partition_resize_work {
+ pthread_t thread_id;
+ struct cds_lfht *ht;
+ unsigned long i, start, len;
+ void (*fct)(struct cds_lfht *ht, unsigned long i,
+ unsigned long start, unsigned long len);
+};
+
+static
+void _cds_lfht_add(struct cds_lfht *ht,
+ unsigned long size,
+ struct cds_lfht_node *node,
+ struct cds_lfht_iter *unique_ret,
+ int dummy);
+
+/*
+ * Algorithm to reverse bits in a word by lookup table, extended to
+ * 64-bit words.
+ * Source:
+ * http://graphics.stanford.edu/~seander/bithacks.html#BitReverseTable
+ * Originally from Public Domain.
+ */
+
+static const uint8_t BitReverseTable256[256] =
+{
+#define R2(n) (n), (n) + 2*64, (n) + 1*64, (n) + 3*64
+#define R4(n) R2(n), R2((n) + 2*16), R2((n) + 1*16), R2((n) + 3*16)
+#define R6(n) R4(n), R4((n) + 2*4 ), R4((n) + 1*4 ), R4((n) + 3*4 )
+ R6(0), R6(2), R6(1), R6(3)
+};
+#undef R2
+#undef R4
+#undef R6
+
+static
+uint8_t bit_reverse_u8(uint8_t v)
+{
+ return BitReverseTable256[v];
+}
+
+static __attribute__((unused))
+uint32_t bit_reverse_u32(uint32_t v)
+{
+ return ((uint32_t) bit_reverse_u8(v) << 24) |
+ ((uint32_t) bit_reverse_u8(v >> 8) << 16) |
+ ((uint32_t) bit_reverse_u8(v >> 16) << 8) |
+ ((uint32_t) bit_reverse_u8(v >> 24));
+}
+
+static __attribute__((unused))
+uint64_t bit_reverse_u64(uint64_t v)
+{
+ return ((uint64_t) bit_reverse_u8(v) << 56) |
+ ((uint64_t) bit_reverse_u8(v >> 8) << 48) |
+ ((uint64_t) bit_reverse_u8(v >> 16) << 40) |
+ ((uint64_t) bit_reverse_u8(v >> 24) << 32) |
+ ((uint64_t) bit_reverse_u8(v >> 32) << 24) |
+ ((uint64_t) bit_reverse_u8(v >> 40) << 16) |
+ ((uint64_t) bit_reverse_u8(v >> 48) << 8) |
+ ((uint64_t) bit_reverse_u8(v >> 56));
+}
+
+static
+unsigned long bit_reverse_ulong(unsigned long v)
+{
+#if (CAA_BITS_PER_LONG == 32)
+ return bit_reverse_u32(v);
+#else
+ return bit_reverse_u64(v);
+#endif
+}
+
+/*
+ * fls: returns the position of the most significant bit.
+ * Returns 0 if no bit is set, else returns the position of the most
+ * significant bit (from 1 to 32 on 32-bit, from 1 to 64 on 64-bit).
+ */
+#if defined(__i386) || defined(__x86_64)
+static inline
+unsigned int fls_u32(uint32_t x)
+{
+ int r;
+
+ asm("bsrl %1,%0\n\t"
+ "jnz 1f\n\t"
+ "movl $-1,%0\n\t"
+ "1:\n\t"
+ : "=r" (r) : "rm" (x));
+ return r + 1;
+}
+#define HAS_FLS_U32
+#endif
+
+#if defined(__x86_64)
+static inline
+unsigned int fls_u64(uint64_t x)
+{
+ long r;
+
+ asm("bsrq %1,%0\n\t"
+ "jnz 1f\n\t"
+ "movq $-1,%0\n\t"
+ "1:\n\t"
+ : "=r" (r) : "rm" (x));
+ return r + 1;
+}
+#define HAS_FLS_U64
+#endif
+
+#ifndef HAS_FLS_U64
+static __attribute__((unused))
+unsigned int fls_u64(uint64_t x)
+{
+ unsigned int r = 64;
+
+ if (!x)
+ return 0;
+
+ if (!(x & 0xFFFFFFFF00000000ULL)) {
+ x <<= 32;
+ r -= 32;
+ }
+ if (!(x & 0xFFFF000000000000ULL)) {
+ x <<= 16;
+ r -= 16;
+ }
+ if (!(x & 0xFF00000000000000ULL)) {
+ x <<= 8;
+ r -= 8;
+ }
+ if (!(x & 0xF000000000000000ULL)) {
+ x <<= 4;
+ r -= 4;
+ }
+ if (!(x & 0xC000000000000000ULL)) {
+ x <<= 2;
+ r -= 2;
+ }
+ if (!(x & 0x8000000000000000ULL)) {
+ x <<= 1;
+ r -= 1;
+ }
+ return r;
+}
+#endif
+
+#ifndef HAS_FLS_U32
+static __attribute__((unused))
+unsigned int fls_u32(uint32_t x)
+{
+ unsigned int r = 32;
+
+ if (!x)
+ return 0;
+ if (!(x & 0xFFFF0000U)) {
+ x <<= 16;
+ r -= 16;
+ }
+ if (!(x & 0xFF000000U)) {
+ x <<= 8;
+ r -= 8;
+ }
+ if (!(x & 0xF0000000U)) {
+ x <<= 4;
+ r -= 4;
+ }
+ if (!(x & 0xC0000000U)) {
+ x <<= 2;
+ r -= 2;
+ }
+ if (!(x & 0x80000000U)) {
+ x <<= 1;
+ r -= 1;
+ }
+ return r;
+}
+#endif
+
+unsigned int fls_ulong(unsigned long x)
+{
+#if (CAA_BITS_PER_LONG == 32)
+ return fls_u32(x);
+#else
+ return fls_u64(x);
+#endif
+}
+
+/*
+ * Return the minimum order for which x <= (1UL << order).
+ * Return -1 if x is 0.
+ */
+int get_count_order_u32(uint32_t x)
+{
+ if (!x)
+ return -1;
+
+ return fls_u32(x - 1);
+}
+
+/*
+ * Return the minimum order for which x <= (1UL << order).
+ * Return -1 if x is 0.
+ */
+int get_count_order_ulong(unsigned long x)
+{
+ if (!x)
+ return -1;
+
+ return fls_ulong(x - 1);
+}
+
+#ifdef POISON_FREE
+#define poison_free(ptr) \
+ do { \
+ if (ptr) { \
+ memset(ptr, 0x42, sizeof(*(ptr))); \
+ free(ptr); \
+ } \
+ } while (0)
+#else
+#define poison_free(ptr) free(ptr)
+#endif
+
+static
+void cds_lfht_resize_lazy(struct cds_lfht *ht, unsigned long size, int growth);
+
+static
+void cds_lfht_resize_lazy_count(struct cds_lfht *ht, unsigned long size,
+ unsigned long count);
+
+static long nr_cpus_mask = -1;
+static long split_count_mask = -1;
+
+#if defined(HAVE_SYSCONF)
+static void ht_init_nr_cpus_mask(void)
+{
+ long maxcpus;
+
+ maxcpus = sysconf(_SC_NPROCESSORS_CONF);
+ if (maxcpus <= 0) {
+ nr_cpus_mask = -2;
+ return;
+ }
+ /*
+ * round up number of CPUs to next power of two, so we
+ * can use & for modulo.
+ */
+ maxcpus = 1UL << get_count_order_ulong(maxcpus);
+ nr_cpus_mask = maxcpus - 1;
+}
+#else /* #if defined(HAVE_SYSCONF) */
+static void ht_init_nr_cpus_mask(void)
+{
+ nr_cpus_mask = -2;
+}
+#endif /* #else #if defined(HAVE_SYSCONF) */
+
+static
+void alloc_split_items_count(struct cds_lfht *ht)
+{
+ struct ht_items_count *count;
+
+ if (nr_cpus_mask == -1) {
+ ht_init_nr_cpus_mask();
+ if (nr_cpus_mask < 0)
+ split_count_mask = DEFAULT_SPLIT_COUNT_MASK;
+ else
+ split_count_mask = nr_cpus_mask;
+ }
+
+ assert(split_count_mask >= 0);
+
+ if (ht->flags & CDS_LFHT_ACCOUNTING) {
+ ht->split_count = calloc(split_count_mask + 1, sizeof(*count));
+ assert(ht->split_count);
+ } else {
+ ht->split_count = NULL;
+ }
+}
+
+static
+void free_split_items_count(struct cds_lfht *ht)
+{
+ poison_free(ht->split_count);
+}
+
+#if defined(HAVE_SCHED_GETCPU)
+static
+int ht_get_split_count_index(unsigned long hash)
+{
+ int cpu;
+
+ assert(split_count_mask >= 0);
+ cpu = sched_getcpu();
+ if (caa_unlikely(cpu < 0))
+ return hash & split_count_mask;
+ else
+ return cpu & split_count_mask;
+}
+#else /* #if defined(HAVE_SCHED_GETCPU) */
+static
+int ht_get_split_count_index(unsigned long hash)
+{
+ return hash & split_count_mask;
+}
+#endif /* #else #if defined(HAVE_SCHED_GETCPU) */
+
+static
+void ht_count_add(struct cds_lfht *ht, unsigned long size, unsigned long hash)
+{
+ unsigned long split_count;
+ int index;
+
+ if (caa_unlikely(!ht->split_count))
+ return;
+ index = ht_get_split_count_index(hash);
+ split_count = uatomic_add_return(&ht->split_count[index].add, 1);
+ if (caa_unlikely(!(split_count & ((1UL << COUNT_COMMIT_ORDER) - 1)))) {
+ long count;
+
+ dbg_printf("add split count %lu\n", split_count);
+ count = uatomic_add_return(&ht->count,
+ 1UL << COUNT_COMMIT_ORDER);
+ /* If power of 2 */
+ if (!(count & (count - 1))) {
+ if ((count >> CHAIN_LEN_RESIZE_THRESHOLD) < size)
+ return;
+ dbg_printf("add set global %ld\n", count);
+ cds_lfht_resize_lazy_count(ht, size,
+ count >> (CHAIN_LEN_TARGET - 1));
+ }
+ }
+}
+
+static
+void ht_count_del(struct cds_lfht *ht, unsigned long size, unsigned long hash)
+{
+ unsigned long split_count;
+ int index;
+
+ if (caa_unlikely(!ht->split_count))
+ return;
+ index = ht_get_split_count_index(hash);
+ split_count = uatomic_add_return(&ht->split_count[index].del, 1);
+ if (caa_unlikely(!(split_count & ((1UL << COUNT_COMMIT_ORDER) - 1)))) {
+ long count;
+
+ dbg_printf("del split count %lu\n", split_count);
+ count = uatomic_add_return(&ht->count,
+ -(1UL << COUNT_COMMIT_ORDER));
+ /* If power of 2 */
+ if (!(count & (count - 1))) {
+ if ((count >> CHAIN_LEN_RESIZE_THRESHOLD) >= size)
+ return;
+ dbg_printf("del set global %ld\n", count);
+ /*
+ * Don't shrink table if the number of nodes is below a
+ * certain threshold.
+ */
+ if (count < (1UL << COUNT_COMMIT_ORDER) * (split_count_mask + 1))
+ return;
+ cds_lfht_resize_lazy_count(ht, size,
+ count >> (CHAIN_LEN_TARGET - 1));
+ }
+ }
+}
+
+static
+void check_resize(struct cds_lfht *ht, unsigned long size, uint32_t chain_len)
+{
+ unsigned long count;
+
+ if (!(ht->flags & CDS_LFHT_AUTO_RESIZE))
+ return;
+ count = uatomic_read(&ht->count);
+ /*
+ * Use bucket-local length for small table expand and for
+ * environments lacking per-cpu data support.
+ */
+ if (count >= (1UL << COUNT_COMMIT_ORDER))
+ return;
+ if (chain_len > 100)
+ dbg_printf("WARNING: large chain length: %u.\n",
+ chain_len);
+ if (chain_len >= CHAIN_LEN_RESIZE_THRESHOLD)
+ cds_lfht_resize_lazy(ht, size,
+ get_count_order_u32(chain_len - (CHAIN_LEN_TARGET - 1)));
+}
+
+static
+struct cds_lfht_node *clear_flag(struct cds_lfht_node *node)
+{
+ return (struct cds_lfht_node *) (((unsigned long) node) & ~FLAGS_MASK);
+}
+
+static
+int is_removed(struct cds_lfht_node *node)
+{
+ return ((unsigned long) node) & REMOVED_FLAG;
+}
+
+static
+struct cds_lfht_node *flag_removed(struct cds_lfht_node *node)
+{
+ return (struct cds_lfht_node *) (((unsigned long) node) | REMOVED_FLAG);
+}
+
+static
+int is_dummy(struct cds_lfht_node *node)
+{
+ return ((unsigned long) node) & DUMMY_FLAG;
+}
+
+static
+struct cds_lfht_node *flag_dummy(struct cds_lfht_node *node)
+{
+ return (struct cds_lfht_node *) (((unsigned long) node) | DUMMY_FLAG);
+}
+
+static
+struct cds_lfht_node *get_end(void)
+{
+ return (struct cds_lfht_node *) END_VALUE;
+}
+
+static
+int is_end(struct cds_lfht_node *node)
+{
+ return clear_flag(node) == (struct cds_lfht_node *) END_VALUE;
+}
+
+static
+unsigned long _uatomic_max(unsigned long *ptr, unsigned long v)
+{
+ unsigned long old1, old2;
+
+ old1 = uatomic_read(ptr);
+ do {
+ old2 = old1;
+ if (old2 >= v)
+ return old2;
+ } while ((old1 = uatomic_cmpxchg(ptr, old2, v)) != old2);
+ return v;
+}
+
+static
+struct _cds_lfht_node *lookup_bucket(struct cds_lfht *ht, unsigned long size,
+ unsigned long hash)
+{
+ unsigned long index, order;
+
+ assert(size > 0);
+ index = hash & (size - 1);
+
+ if (index < ht->min_alloc_size) {
+ dbg_printf("lookup hash %lu index %lu order 0 aridx 0\n",
+ hash, index);
+ return &ht->t.tbl[0]->nodes[index];
+ }
+ /*
+ * equivalent to get_count_order_ulong(index + 1), but optimizes
+ * away the non-existing 0 special-case for
+ * get_count_order_ulong.
+ */
+ order = fls_ulong(index);
+ dbg_printf("lookup hash %lu index %lu order %lu aridx %lu\n",
+ hash, index, order, index & ((1UL << (order - 1)) - 1));
+ return &ht->t.tbl[order]->nodes[index & ((1UL << (order - 1)) - 1)];
+}
+
+/*
+ * Remove all logically deleted nodes from a bucket up to a certain node key.
+ */
+static
+void _cds_lfht_gc_bucket(struct cds_lfht_node *dummy, struct cds_lfht_node *node)
+{
+ struct cds_lfht_node *iter_prev, *iter, *next, *new_next;
+
+ assert(!is_dummy(dummy));
+ assert(!is_removed(dummy));
+ assert(!is_dummy(node));
+ assert(!is_removed(node));
+ for (;;) {
+ iter_prev = dummy;
+ /* We can always skip the dummy node initially */
+ iter = rcu_dereference(iter_prev->p.next);
+ assert(!is_removed(iter));
+ assert(iter_prev->p.reverse_hash <= node->p.reverse_hash);
+ /*
+ * We should never be called with dummy (start of chain)
+ * and logically removed node (end of path compression
+ * marker) being the actual same node. This would be a
+ * bug in the algorithm implementation.
+ */
+ assert(dummy != node);
+ for (;;) {
+ if (caa_unlikely(is_end(iter)))
+ return;
+ if (caa_likely(clear_flag(iter)->p.reverse_hash > node->p.reverse_hash))
+ return;
+ next = rcu_dereference(clear_flag(iter)->p.next);
+ if (caa_likely(is_removed(next)))
+ break;
+ iter_prev = clear_flag(iter);
+ iter = next;
+ }
+ assert(!is_removed(iter));
+ if (is_dummy(iter))
+ new_next = flag_dummy(clear_flag(next));
+ else
+ new_next = clear_flag(next);
+ (void) uatomic_cmpxchg(&iter_prev->p.next, iter, new_next);
+ }
+ return;
+}
+
+static
+int _cds_lfht_replace(struct cds_lfht *ht, unsigned long size,
+ struct cds_lfht_node *old_node,
+ struct cds_lfht_node *old_next,
+ struct cds_lfht_node *new_node)
+{
+ struct cds_lfht_node *dummy, *ret_next;
+ struct _cds_lfht_node *lookup;
+
+ if (!old_node) /* Return -ENOENT if asked to replace NULL node */
+ return -ENOENT;
+
+ assert(!is_removed(old_node));
+ assert(!is_dummy(old_node));
+ assert(!is_removed(new_node));
+ assert(!is_dummy(new_node));
+ assert(new_node != old_node);
+ for (;;) {
+ /* Insert after node to be replaced */
+ if (is_removed(old_next)) {
+ /*
+ * Too late, the old node has been removed under us
+ * between lookup and replace. Fail.
+ */
+ return -ENOENT;
+ }
+ assert(!is_dummy(old_next));
+ assert(new_node != clear_flag(old_next));
+ new_node->p.next = clear_flag(old_next);
+ /*
+ * Here is the whole trick for lock-free replace: we add
+ * the replacement node _after_ the node we want to
+ * replace by atomically setting its next pointer at the
+ * same time we set its removal flag. Given that
+ * the lookups/get next use an iterator aware of the
+ * next pointer, they will either skip the old node due
+ * to the removal flag and see the new node, or use
+ * the old node, but will not see the new one.
+ */
+ ret_next = uatomic_cmpxchg(&old_node->p.next,
+ old_next, flag_removed(new_node));
+ if (ret_next == old_next)
+ break; /* We performed the replacement. */
+ old_next = ret_next;
+ }
+
+ /*
+ * Ensure that the old node is not visible to readers anymore:
+ * lookup for the node, and remove it (along with any other
+ * logically removed node) if found.
+ */
+ lookup = lookup_bucket(ht, size, bit_reverse_ulong(old_node->p.reverse_hash));
+ dummy = (struct cds_lfht_node *) lookup;
+ _cds_lfht_gc_bucket(dummy, new_node);
+
+ assert(is_removed(rcu_dereference(old_node->p.next)));
+ return 0;
+}
+
+/*
+ * A non-NULL unique_ret pointer uses the "add unique" (or uniquify) add
+ * mode. A NULL unique_ret allows creation of duplicate keys.
+ */
+static
+void _cds_lfht_add(struct cds_lfht *ht,
+ unsigned long size,
+ struct cds_lfht_node *node,
+ struct cds_lfht_iter *unique_ret,
+ int dummy)
+{
+ struct cds_lfht_node *iter_prev, *iter, *next, *new_node, *new_next,
+ *return_node;
+ struct _cds_lfht_node *lookup;
+
+ assert(!is_dummy(node));
+ assert(!is_removed(node));
+ lookup = lookup_bucket(ht, size, bit_reverse_ulong(node->p.reverse_hash));
+ for (;;) {
+ uint32_t chain_len = 0;
+
+ /*
+ * iter_prev points to the non-removed node prior to the
+ * insert location.
+ */
+ iter_prev = (struct cds_lfht_node *) lookup;
+ /* We can always skip the dummy node initially */
+ iter = rcu_dereference(iter_prev->p.next);
+ assert(iter_prev->p.reverse_hash <= node->p.reverse_hash);
+ for (;;) {
+ if (caa_unlikely(is_end(iter)))
+ goto insert;
+ if (caa_likely(clear_flag(iter)->p.reverse_hash > node->p.reverse_hash))
+ goto insert;
+
+ /* dummy node is the first node of the identical-hash-value chain */
+ if (dummy && clear_flag(iter)->p.reverse_hash == node->p.reverse_hash)
+ goto insert;
+
+ next = rcu_dereference(clear_flag(iter)->p.next);
+ if (caa_unlikely(is_removed(next)))
+ goto gc_node;
+
+ /* uniquely add */
+ if (unique_ret
+ && !is_dummy(next)
+ && clear_flag(iter)->p.reverse_hash == node->p.reverse_hash) {
+ struct cds_lfht_iter d_iter = { .node = node, .next = iter, };
+
+ /*
+ * uniquely adding inserts the node as the first
+ * node of the identical-hash-value node chain.
+ *
+ * This semantic ensures no duplicated keys
+ * should ever be observable in the table
+ * (including observe one node by one node
+ * by forward iterations)
+ */
+ cds_lfht_next_duplicate(ht, &d_iter);
+ if (!d_iter.node)
+ goto insert;
+
+ *unique_ret = d_iter;
+ return;
+ }
+
+ /* Only account for identical reverse hash once */
+ if (iter_prev->p.reverse_hash != clear_flag(iter)->p.reverse_hash
+ && !is_dummy(next))
+ check_resize(ht, size, ++chain_len);
+ iter_prev = clear_flag(iter);
+ iter = next;
+ }
+
+ insert:
+ assert(node != clear_flag(iter));
+ assert(!is_removed(iter_prev));
+ assert(!is_removed(iter));
+ assert(iter_prev != node);
+ if (!dummy)
+ node->p.next = clear_flag(iter);
+ else
+ node->p.next = flag_dummy(clear_flag(iter));
+ if (is_dummy(iter))
+ new_node = flag_dummy(node);
+ else
+ new_node = node;
+ if (uatomic_cmpxchg(&iter_prev->p.next, iter,
+ new_node) != iter) {
+ continue; /* retry */
+ } else {
+ return_node = node;
+ goto end;
+ }
+
+ gc_node:
+ assert(!is_removed(iter));
+ if (is_dummy(iter))
+ new_next = flag_dummy(clear_flag(next));
+ else
+ new_next = clear_flag(next);
+ (void) uatomic_cmpxchg(&iter_prev->p.next, iter, new_next);
+ /* retry */
+ }
+end:
+ if (unique_ret) {
+ unique_ret->node = return_node;
+ /* unique_ret->next left unset, never used. */
+ }
+}
+
+static
+int _cds_lfht_del(struct cds_lfht *ht, unsigned long size,
+ struct cds_lfht_node *node,
+ int dummy_removal)
+{
+ struct cds_lfht_node *dummy, *next, *old;
+ struct _cds_lfht_node *lookup;
+
+ if (!node) /* Return -ENOENT if asked to delete NULL node */
+ return -ENOENT;
+
+ /* logically delete the node */
+ assert(!is_dummy(node));
+ assert(!is_removed(node));
+ old = rcu_dereference(node->p.next);
+ do {
+ struct cds_lfht_node *new_next;
+
+ next = old;
+ if (caa_unlikely(is_removed(next)))
+ return -ENOENT;
+ if (dummy_removal)
+ assert(is_dummy(next));
+ else
+ assert(!is_dummy(next));
+ new_next = flag_removed(next);
+ old = uatomic_cmpxchg(&node->p.next, next, new_next);
+ } while (old != next);
+ /* We performed the (logical) deletion. */
+
+ /*
+ * Ensure that the node is not visible to readers anymore: lookup for
+ * the node, and remove it (along with any other logically removed node)
+ * if found.
+ */
+ lookup = lookup_bucket(ht, size, bit_reverse_ulong(node->p.reverse_hash));
+ dummy = (struct cds_lfht_node *) lookup;
+ _cds_lfht_gc_bucket(dummy, node);
+
+ assert(is_removed(rcu_dereference(node->p.next)));
+ return 0;
+}
+
+static
+void *partition_resize_thread(void *arg)
+{
+ struct partition_resize_work *work = arg;
+
+ work->ht->cds_lfht_rcu_register_thread();
+ work->fct(work->ht, work->i, work->start, work->len);
+ work->ht->cds_lfht_rcu_unregister_thread();
+ return NULL;
+}
+
+static
+void partition_resize_helper(struct cds_lfht *ht, unsigned long i,
+ unsigned long len,
+ void (*fct)(struct cds_lfht *ht, unsigned long i,
+ unsigned long start, unsigned long len))
+{
+ unsigned long partition_len;
+ struct partition_resize_work *work;
+ int thread, ret;
+ unsigned long nr_threads;
+
+ /*
+ * Note: nr_cpus_mask + 1 is always power of 2.
+ * We spawn just the number of threads we need to satisfy the minimum
+ * partition size, up to the number of CPUs in the system.
+ */
+ if (nr_cpus_mask > 0) {
+ nr_threads = min(nr_cpus_mask + 1,
+ len >> MIN_PARTITION_PER_THREAD_ORDER);
+ } else {
+ nr_threads = 1;
+ }
+ partition_len = len >> get_count_order_ulong(nr_threads);
+ work = calloc(nr_threads, sizeof(*work));
+ assert(work);
+ for (thread = 0; thread < nr_threads; thread++) {
+ work[thread].ht = ht;
+ work[thread].i = i;
+ work[thread].len = partition_len;
+ work[thread].start = thread * partition_len;
+ work[thread].fct = fct;
+ ret = pthread_create(&(work[thread].thread_id), ht->resize_attr,
+ partition_resize_thread, &work[thread]);
+ assert(!ret);
+ }
+ for (thread = 0; thread < nr_threads; thread++) {
+ ret = pthread_join(work[thread].thread_id, NULL);
+ assert(!ret);
+ }
+ free(work);
+}
+
+/*
+ * Holding RCU read lock to protect _cds_lfht_add against memory
+ * reclaim that could be performed by other call_rcu worker threads (ABA
+ * problem).
+ *
+ * When we reach a certain length, we can split this population phase over
+ * many worker threads, based on the number of CPUs available in the system.
+ * This should therefore take care of not having the expand lagging behind too
+ * many concurrent insertion threads by using the scheduler's ability to
+ * schedule dummy node population fairly with insertions.
+ */
+static
+void init_table_populate_partition(struct cds_lfht *ht, unsigned long i,
+ unsigned long start, unsigned long len)
+{
+ unsigned long j;
+
+ assert(i > ht->min_alloc_order);
+ ht->cds_lfht_rcu_read_lock();
+ for (j = start; j < start + len; j++) {
+ struct cds_lfht_node *new_node =
+ (struct cds_lfht_node *) &ht->t.tbl[i]->nodes[j];
+
+ dbg_printf("init populate: i %lu j %lu hash %lu\n",
+ i, j, (1UL << (i - 1)) + j);
+ new_node->p.reverse_hash =
+ bit_reverse_ulong((1UL << (i - 1)) + j);
+ _cds_lfht_add(ht, 1UL << (i - 1),
+ new_node, NULL, 1);
+ }
+ ht->cds_lfht_rcu_read_unlock();
+}
+
+static
+void init_table_populate(struct cds_lfht *ht, unsigned long i,
+ unsigned long len)
+{
+ assert(nr_cpus_mask != -1);
+ if (nr_cpus_mask < 0 || len < 2 * MIN_PARTITION_PER_THREAD) {
+ ht->cds_lfht_rcu_thread_online();
+ init_table_populate_partition(ht, i, 0, len);
+ ht->cds_lfht_rcu_thread_offline();
+ return;
+ }
+ partition_resize_helper(ht, i, len, init_table_populate_partition);
+}
+
+static
+void init_table(struct cds_lfht *ht,
+ unsigned long first_order, unsigned long last_order)
+{
+ unsigned long i;
+
+ dbg_printf("init table: first_order %lu last_order %lu\n",
+ first_order, last_order);
+ assert(first_order > ht->min_alloc_order);
+ for (i = first_order; i <= last_order; i++) {
+ unsigned long len;
+
+ len = 1UL << (i - 1);
+ dbg_printf("init order %lu len: %lu\n", i, len);
+
+ /* Stop expand if the resize target changes under us */
+ if (CMM_LOAD_SHARED(ht->t.resize_target) < (1UL << i))
+ break;
+
+ ht->t.tbl[i] = calloc(1, len * sizeof(struct _cds_lfht_node));
+ assert(ht->t.tbl[i]);
+
+ /*
+ * Set all dummy nodes reverse hash values for a level and
+ * link all dummy nodes into the table.
+ */
+ init_table_populate(ht, i, len);
+
+ /*
+ * Update table size.
+ */
+ cmm_smp_wmb(); /* populate data before RCU size */
+ CMM_STORE_SHARED(ht->t.size, 1UL << i);
+
+ dbg_printf("init new size: %lu\n", 1UL << i);
+ if (CMM_LOAD_SHARED(ht->in_progress_destroy))
+ break;
+ }
+}
+
+/*
+ * Holding RCU read lock to protect _cds_lfht_remove against memory
+ * reclaim that could be performed by other call_rcu worker threads (ABA
+ * problem).
+ * For a single level, we logically remove and garbage collect each node.
+ *
+ * As a design choice, we perform logical removal and garbage collection on a
+ * node-per-node basis to simplify this algorithm. We also assume keeping good
+ * cache locality of the operation would overweight possible performance gain
+ * that could be achieved by batching garbage collection for multiple levels.
+ * However, this would have to be justified by benchmarks.
+ *
+ * Concurrent removal and add operations are helping us perform garbage
+ * collection of logically removed nodes. We guarantee that all logically
+ * removed nodes have been garbage-collected (unlinked) before call_rcu is
+ * invoked to free a hole level of dummy nodes (after a grace period).
+ *
+ * Logical removal and garbage collection can therefore be done in batch or on a
+ * node-per-node basis, as long as the guarantee above holds.
+ *
+ * When we reach a certain length, we can split this removal over many worker
+ * threads, based on the number of CPUs available in the system. This should
+ * take care of not letting resize process lag behind too many concurrent
+ * updater threads actively inserting into the hash table.
+ */
+static
+void remove_table_partition(struct cds_lfht *ht, unsigned long i,
+ unsigned long start, unsigned long len)
+{
+ unsigned long j;
+
+ assert(i > ht->min_alloc_order);
+ ht->cds_lfht_rcu_read_lock();
+ for (j = start; j < start + len; j++) {
+ struct cds_lfht_node *fini_node =
+ (struct cds_lfht_node *) &ht->t.tbl[i]->nodes[j];
+
+ dbg_printf("remove entry: i %lu j %lu hash %lu\n",
+ i, j, (1UL << (i - 1)) + j);
+ fini_node->p.reverse_hash =
+ bit_reverse_ulong((1UL << (i - 1)) + j);
+ (void) _cds_lfht_del(ht, 1UL << (i - 1), fini_node, 1);
+ }
+ ht->cds_lfht_rcu_read_unlock();
+}
+
+static
+void remove_table(struct cds_lfht *ht, unsigned long i, unsigned long len)
+{
+
+ assert(nr_cpus_mask != -1);
+ if (nr_cpus_mask < 0 || len < 2 * MIN_PARTITION_PER_THREAD) {
+ ht->cds_lfht_rcu_thread_online();
+ remove_table_partition(ht, i, 0, len);
+ ht->cds_lfht_rcu_thread_offline();
+ return;
+ }
+ partition_resize_helper(ht, i, len, remove_table_partition);
+}
+
+static
+void fini_table(struct cds_lfht *ht,
+ unsigned long first_order, unsigned long last_order)
+{
+ long i;
+ void *free_by_rcu = NULL;
+
+ dbg_printf("fini table: first_order %lu last_order %lu\n",
+ first_order, last_order);
+ assert(first_order > ht->min_alloc_order);
+ for (i = last_order; i >= first_order; i--) {
+ unsigned long len;
+
+ len = 1UL << (i - 1);
+ dbg_printf("fini order %lu len: %lu\n", i, len);
+
+ /* Stop shrink if the resize target changes under us */
+ if (CMM_LOAD_SHARED(ht->t.resize_target) > (1UL << (i - 1)))
+ break;
+
+ cmm_smp_wmb(); /* populate data before RCU size */
+ CMM_STORE_SHARED(ht->t.size, 1UL << (i - 1));
+
+ /*
+ * We need to wait for all add operations to reach Q.S. (and
+ * thus use the new table for lookups) before we can start
+ * releasing the old dummy nodes. Otherwise their lookup will
+ * return a logically removed node as insert position.
+ */
+ ht->cds_lfht_synchronize_rcu();
+ if (free_by_rcu)
+ free(free_by_rcu);
+
+ /*
+ * Set "removed" flag in dummy nodes about to be removed.
+ * Unlink all now-logically-removed dummy node pointers.
+ * Concurrent add/remove operation are helping us doing
+ * the gc.
+ */
+ remove_table(ht, i, len);
+
+ free_by_rcu = ht->t.tbl[i];
+
+ dbg_printf("fini new size: %lu\n", 1UL << i);
+ if (CMM_LOAD_SHARED(ht->in_progress_destroy))
+ break;
+ }
+
+ if (free_by_rcu) {
+ ht->cds_lfht_synchronize_rcu();
+ free(free_by_rcu);
+ }
+}
+
+static
+void cds_lfht_create_dummy(struct cds_lfht *ht, unsigned long size)
+{
+ struct _cds_lfht_node *prev, *node;
+ unsigned long order, len, i, j;
+
+ ht->t.tbl[0] = calloc(1, ht->min_alloc_size * sizeof(struct _cds_lfht_node));
+ assert(ht->t.tbl[0]);
+
+ dbg_printf("create dummy: order %lu index %lu hash %lu\n", 0, 0, 0);
+ ht->t.tbl[0]->nodes[0].next = flag_dummy(get_end());
+ ht->t.tbl[0]->nodes[0].reverse_hash = 0;
+
+ for (order = 1; order < get_count_order_ulong(size) + 1; order++) {
+ len = 1UL << (order - 1);
+ if (order <= ht->min_alloc_order) {
+ ht->t.tbl[order] = (struct rcu_level *) (ht->t.tbl[0]->nodes + len);
+ } else {
+ ht->t.tbl[order] = calloc(1, len * sizeof(struct _cds_lfht_node));
+ assert(ht->t.tbl[order]);
+ }
+
+ i = 0;
+ prev = ht->t.tbl[i]->nodes;
+ for (j = 0; j < len; j++) {
+ if (j & (j - 1)) { /* Between power of 2 */
+ prev++;
+ } else if (j) { /* At each power of 2 */
+ i++;
+ prev = ht->t.tbl[i]->nodes;
+ }
+
+ node = &ht->t.tbl[order]->nodes[j];
+ dbg_printf("create dummy: order %lu index %lu hash %lu\n",
+ order, j, j + len);
+ node->next = prev->next;
+ assert(is_dummy(node->next));
+ node->reverse_hash = bit_reverse_ulong(j + len);
+ prev->next = flag_dummy((struct cds_lfht_node *)node);
+ }
+ }
+}
+
+struct cds_lfht *_cds_lfht_new(cds_lfht_hash_fct hash_fct,
+ cds_lfht_compare_fct compare_fct,
+ unsigned long hash_seed,
+ unsigned long init_size,
+ unsigned long min_alloc_size,
+ int flags,
+ void (*cds_lfht_call_rcu)(struct rcu_head *head,
+ void (*func)(struct rcu_head *head)),
+ void (*cds_lfht_synchronize_rcu)(void),
+ void (*cds_lfht_rcu_read_lock)(void),
+ void (*cds_lfht_rcu_read_unlock)(void),
+ void (*cds_lfht_rcu_thread_offline)(void),
+ void (*cds_lfht_rcu_thread_online)(void),
+ void (*cds_lfht_rcu_register_thread)(void),
+ void (*cds_lfht_rcu_unregister_thread)(void),
+ pthread_attr_t *attr)
+{
+ struct cds_lfht *ht;
+ unsigned long order;
+
+ /* min_alloc_size must be power of two */
+ if (!min_alloc_size || (min_alloc_size & (min_alloc_size - 1)))
+ return NULL;
+ /* init_size must be power of two */
+ if (!init_size || (init_size & (init_size - 1)))
+ return NULL;
+ min_alloc_size = max(min_alloc_size, MIN_TABLE_SIZE);
+ init_size = max(init_size, min_alloc_size);
+ ht = calloc(1, sizeof(struct cds_lfht));
+ assert(ht);
+ ht->flags = flags;
+ ht->hash_fct = hash_fct;
+ ht->compare_fct = compare_fct;
+ ht->hash_seed = hash_seed;
+ ht->cds_lfht_call_rcu = cds_lfht_call_rcu;
+ ht->cds_lfht_synchronize_rcu = cds_lfht_synchronize_rcu;
+ ht->cds_lfht_rcu_read_lock = cds_lfht_rcu_read_lock;
+ ht->cds_lfht_rcu_read_unlock = cds_lfht_rcu_read_unlock;
+ ht->cds_lfht_rcu_thread_offline = cds_lfht_rcu_thread_offline;
+ ht->cds_lfht_rcu_thread_online = cds_lfht_rcu_thread_online;
+ ht->cds_lfht_rcu_register_thread = cds_lfht_rcu_register_thread;
+ ht->cds_lfht_rcu_unregister_thread = cds_lfht_rcu_unregister_thread;
+ ht->resize_attr = attr;
+ alloc_split_items_count(ht);
+ /* this mutex should not nest in read-side C.S. */
+ pthread_mutex_init(&ht->resize_mutex, NULL);
+ order = get_count_order_ulong(init_size);
+ ht->t.resize_target = 1UL << order;
+ ht->min_alloc_size = min_alloc_size;
+ ht->min_alloc_order = get_count_order_ulong(min_alloc_size);
+ cds_lfht_create_dummy(ht, 1UL << order);
+ ht->t.size = 1UL << order;
+ return ht;
+}
+
+void cds_lfht_lookup(struct cds_lfht *ht, void *key, size_t key_len,
+ struct cds_lfht_iter *iter)
+{
+ struct cds_lfht_node *node, *next, *dummy_node;
+ struct _cds_lfht_node *lookup;
+ unsigned long hash, reverse_hash, size;
+
+ hash = ht->hash_fct(key, key_len, ht->hash_seed);
+ reverse_hash = bit_reverse_ulong(hash);
+
+ size = rcu_dereference(ht->t.size);
+ lookup = lookup_bucket(ht, size, hash);
+ dummy_node = (struct cds_lfht_node *) lookup;
+ /* We can always skip the dummy node initially */
+ node = rcu_dereference(dummy_node->p.next);
+ node = clear_flag(node);
+ for (;;) {
+ if (caa_unlikely(is_end(node))) {
+ node = next = NULL;
+ break;
+ }
+ if (caa_unlikely(node->p.reverse_hash > reverse_hash)) {
+ node = next = NULL;
+ break;
+ }
+ next = rcu_dereference(node->p.next);
+ assert(node == clear_flag(node));
+ if (caa_likely(!is_removed(next))
+ && !is_dummy(next)
+ && node->p.reverse_hash == reverse_hash
+ && caa_likely(!ht->compare_fct(node->key, node->key_len, key, key_len))) {
+ break;
+ }
+ node = clear_flag(next);
+ }
+ assert(!node || !is_dummy(rcu_dereference(node->p.next)));
+ iter->node = node;
+ iter->next = next;
+}
+
+void cds_lfht_next_duplicate(struct cds_lfht *ht, struct cds_lfht_iter *iter)
+{
+ struct cds_lfht_node *node, *next;
+ unsigned long reverse_hash;
+ void *key;
+ size_t key_len;
+
+ node = iter->node;
+ reverse_hash = node->p.reverse_hash;
+ key = node->key;
+ key_len = node->key_len;
+ next = iter->next;
+ node = clear_flag(next);
+
+ for (;;) {
+ if (caa_unlikely(is_end(node))) {
+ node = next = NULL;
+ break;
+ }
+ if (caa_unlikely(node->p.reverse_hash > reverse_hash)) {
+ node = next = NULL;
+ break;
+ }
+ next = rcu_dereference(node->p.next);
+ if (caa_likely(!is_removed(next))
+ && !is_dummy(next)
+ && caa_likely(!ht->compare_fct(node->key, node->key_len, key, key_len))) {
+ break;
+ }
+ node = clear_flag(next);
+ }
+ assert(!node || !is_dummy(rcu_dereference(node->p.next)));
+ iter->node = node;
+ iter->next = next;
+}
+
+void cds_lfht_next(struct cds_lfht *ht, struct cds_lfht_iter *iter)
+{
+ struct cds_lfht_node *node, *next;
+
+ node = clear_flag(iter->next);
+ for (;;) {
+ if (caa_unlikely(is_end(node))) {
+ node = next = NULL;
+ break;
+ }
+ next = rcu_dereference(node->p.next);
+ if (caa_likely(!is_removed(next))
+ && !is_dummy(next)) {
+ break;
+ }
+ node = clear_flag(next);
+ }
+ assert(!node || !is_dummy(rcu_dereference(node->p.next)));
+ iter->node = node;
+ iter->next = next;
+}
+
+void cds_lfht_first(struct cds_lfht *ht, struct cds_lfht_iter *iter)
+{
+ struct _cds_lfht_node *lookup;
+
+ /*
+ * Get next after first dummy node. The first dummy node is the
+ * first node of the linked list.
+ */
+ lookup = &ht->t.tbl[0]->nodes[0];
+ iter->next = lookup->next;
+ cds_lfht_next(ht, iter);
+}
+
+void cds_lfht_add(struct cds_lfht *ht, struct cds_lfht_node *node)
+{
+ unsigned long hash, size;
+
+ hash = ht->hash_fct(node->key, node->key_len, ht->hash_seed);
+ node->p.reverse_hash = bit_reverse_ulong((unsigned long) hash);
+
+ size = rcu_dereference(ht->t.size);
+ _cds_lfht_add(ht, size, node, NULL, 0);
+ ht_count_add(ht, size, hash);
+}
+
+struct cds_lfht_node *cds_lfht_add_unique(struct cds_lfht *ht,
+ struct cds_lfht_node *node)
+{
+ unsigned long hash, size;
+ struct cds_lfht_iter iter;
+
+ hash = ht->hash_fct(node->key, node->key_len, ht->hash_seed);
+ node->p.reverse_hash = bit_reverse_ulong((unsigned long) hash);
+
+ size = rcu_dereference(ht->t.size);
+ _cds_lfht_add(ht, size, node, &iter, 0);
+ if (iter.node == node)
+ ht_count_add(ht, size, hash);
+ return iter.node;
+}
+
+struct cds_lfht_node *cds_lfht_add_replace(struct cds_lfht *ht,
+ struct cds_lfht_node *node)
+{
+ unsigned long hash, size;
+ struct cds_lfht_iter iter;
+
+ hash = ht->hash_fct(node->key, node->key_len, ht->hash_seed);
+ node->p.reverse_hash = bit_reverse_ulong((unsigned long) hash);
+
+ size = rcu_dereference(ht->t.size);
+ for (;;) {
+ _cds_lfht_add(ht, size, node, &iter, 0);
+ if (iter.node == node) {
+ ht_count_add(ht, size, hash);
+ return NULL;
+ }
+
+ if (!_cds_lfht_replace(ht, size, iter.node, iter.next, node))
+ return iter.node;
+ }
+}
+
+int cds_lfht_replace(struct cds_lfht *ht, struct cds_lfht_iter *old_iter,
+ struct cds_lfht_node *new_node)
+{
+ unsigned long size;
+
+ size = rcu_dereference(ht->t.size);
+ return _cds_lfht_replace(ht, size, old_iter->node, old_iter->next,
+ new_node);
+}
+
+int cds_lfht_del(struct cds_lfht *ht, struct cds_lfht_iter *iter)
+{
+ unsigned long size, hash;
+ int ret;
+
+ size = rcu_dereference(ht->t.size);
+ ret = _cds_lfht_del(ht, size, iter->node, 0);
+ if (!ret) {
+ hash = bit_reverse_ulong(iter->node->p.reverse_hash);
+ ht_count_del(ht, size, hash);
+ }
+ return ret;
+}
+
+static
+int cds_lfht_delete_dummy(struct cds_lfht *ht)
+{
+ struct cds_lfht_node *node;
+ struct _cds_lfht_node *lookup;
+ unsigned long order, i, size;
+
+ /* Check that the table is empty */
+ lookup = &ht->t.tbl[0]->nodes[0];
+ node = (struct cds_lfht_node *) lookup;
+ do {
+ node = clear_flag(node)->p.next;
+ if (!is_dummy(node))
+ return -EPERM;
+ assert(!is_removed(node));
+ } while (!is_end(node));
+ /*
+ * size accessed without rcu_dereference because hash table is
+ * being destroyed.
+ */
+ size = ht->t.size;
+ /* Internal sanity check: all nodes left should be dummy */
+ for (order = 0; order < get_count_order_ulong(size) + 1; order++) {
+ unsigned long len;
+
+ len = !order ? 1 : 1UL << (order - 1);
+ for (i = 0; i < len; i++) {
+ dbg_printf("delete order %lu i %lu hash %lu\n",
+ order, i,
+ bit_reverse_ulong(ht->t.tbl[order]->nodes[i].reverse_hash));
+ assert(is_dummy(ht->t.tbl[order]->nodes[i].next));
+ }
+
+ if (order == ht->min_alloc_order)
+ poison_free(ht->t.tbl[0]);
+ else if (order > ht->min_alloc_order)
+ poison_free(ht->t.tbl[order]);
+ /* Nothing to delete for order < ht->min_alloc_order */
+ }
+ return 0;
+}
+
+/*
+ * Should only be called when no more concurrent readers nor writers can
+ * possibly access the table.
+ */
+int cds_lfht_destroy(struct cds_lfht *ht, pthread_attr_t **attr)
+{
+ int ret;
+
+ /* Wait for in-flight resize operations to complete */
+ _CMM_STORE_SHARED(ht->in_progress_destroy, 1);
+ cmm_smp_mb(); /* Store destroy before load resize */
+ while (uatomic_read(&ht->in_progress_resize))
+ poll(NULL, 0, 100); /* wait for 100ms */
+ ret = cds_lfht_delete_dummy(ht);
+ if (ret)
+ return ret;
+ free_split_items_count(ht);
+ if (attr)
+ *attr = ht->resize_attr;
+ poison_free(ht);
+ return ret;
+}
+
+void cds_lfht_count_nodes(struct cds_lfht *ht,
+ long *approx_before,
+ unsigned long *count,
+ unsigned long *removed,
+ long *approx_after)
+{
+ struct cds_lfht_node *node, *next;
+ struct _cds_lfht_node *lookup;
+ unsigned long nr_dummy = 0;
+
+ *approx_before = 0;
+ if (ht->split_count) {
+ int i;
+
+ for (i = 0; i < split_count_mask + 1; i++) {
+ *approx_before += uatomic_read(&ht->split_count[i].add);
+ *approx_before -= uatomic_read(&ht->split_count[i].del);
+ }
+ }
+
+ *count = 0;
+ *removed = 0;
+
+ /* Count non-dummy nodes in the table */
+ lookup = &ht->t.tbl[0]->nodes[0];
+ node = (struct cds_lfht_node *) lookup;
+ do {
+ next = rcu_dereference(node->p.next);
+ if (is_removed(next)) {
+ if (!is_dummy(next))
+ (*removed)++;
+ else
+ (nr_dummy)++;
+ } else if (!is_dummy(next))
+ (*count)++;
+ else
+ (nr_dummy)++;
+ node = clear_flag(next);
+ } while (!is_end(node));
+ dbg_printf("number of dummy nodes: %lu\n", nr_dummy);
+ *approx_after = 0;
+ if (ht->split_count) {
+ int i;
+
+ for (i = 0; i < split_count_mask + 1; i++) {
+ *approx_after += uatomic_read(&ht->split_count[i].add);
+ *approx_after -= uatomic_read(&ht->split_count[i].del);
+ }
+ }
+}
+
+/* called with resize mutex held */
+static
+void _do_cds_lfht_grow(struct cds_lfht *ht,
+ unsigned long old_size, unsigned long new_size)
+{
+ unsigned long old_order, new_order;
+
+ old_order = get_count_order_ulong(old_size);
+ new_order = get_count_order_ulong(new_size);
+ dbg_printf("resize from %lu (order %lu) to %lu (order %lu) buckets\n",
+ old_size, old_order, new_size, new_order);
+ assert(new_size > old_size);
+ init_table(ht, old_order + 1, new_order);
+}
+
+/* called with resize mutex held */
+static
+void _do_cds_lfht_shrink(struct cds_lfht *ht,
+ unsigned long old_size, unsigned long new_size)
+{
+ unsigned long old_order, new_order;
+
+ new_size = max(new_size, ht->min_alloc_size);
+ old_order = get_count_order_ulong(old_size);
+ new_order = get_count_order_ulong(new_size);
+ dbg_printf("resize from %lu (order %lu) to %lu (order %lu) buckets\n",
+ old_size, old_order, new_size, new_order);
+ assert(new_size < old_size);
+
+ /* Remove and unlink all dummy nodes to remove. */
+ fini_table(ht, new_order + 1, old_order);
+}
+
+
+/* called with resize mutex held */
+static
+void _do_cds_lfht_resize(struct cds_lfht *ht)
+{
+ unsigned long new_size, old_size;
+
+ /*
+ * Resize table, re-do if the target size has changed under us.
+ */
+ do {
+ assert(uatomic_read(&ht->in_progress_resize));
+ if (CMM_LOAD_SHARED(ht->in_progress_destroy))
+ break;
+ ht->t.resize_initiated = 1;
+ old_size = ht->t.size;
+ new_size = CMM_LOAD_SHARED(ht->t.resize_target);
+ if (old_size < new_size)
+ _do_cds_lfht_grow(ht, old_size, new_size);
+ else if (old_size > new_size)
+ _do_cds_lfht_shrink(ht, old_size, new_size);
+ ht->t.resize_initiated = 0;
+ /* write resize_initiated before read resize_target */
+ cmm_smp_mb();
+ } while (ht->t.size != CMM_LOAD_SHARED(ht->t.resize_target));
+}
+
+static
+unsigned long resize_target_update(struct cds_lfht *ht, unsigned long size,
+ int growth_order)
+{
+ return _uatomic_max(&ht->t.resize_target,
+ size << growth_order);
+}
+
+static
+void resize_target_update_count(struct cds_lfht *ht,
+ unsigned long count)
+{
+ count = max(count, ht->min_alloc_size);
+ uatomic_set(&ht->t.resize_target, count);
+}
+
+void cds_lfht_resize(struct cds_lfht *ht, unsigned long new_size)
+{
+ resize_target_update_count(ht, new_size);
+ CMM_STORE_SHARED(ht->t.resize_initiated, 1);
+ ht->cds_lfht_rcu_thread_offline();
+ pthread_mutex_lock(&ht->resize_mutex);
+ _do_cds_lfht_resize(ht);
+ pthread_mutex_unlock(&ht->resize_mutex);
+ ht->cds_lfht_rcu_thread_online();
+}
+
+static
+void do_resize_cb(struct rcu_head *head)
+{
+ struct rcu_resize_work *work =
+ caa_container_of(head, struct rcu_resize_work, head);
+ struct cds_lfht *ht = work->ht;
+
+ ht->cds_lfht_rcu_thread_offline();
+ pthread_mutex_lock(&ht->resize_mutex);
+ _do_cds_lfht_resize(ht);
+ pthread_mutex_unlock(&ht->resize_mutex);
+ ht->cds_lfht_rcu_thread_online();
+ poison_free(work);
+ cmm_smp_mb(); /* finish resize before decrement */
+ uatomic_dec(&ht->in_progress_resize);
+}
+
+static
+void cds_lfht_resize_lazy(struct cds_lfht *ht, unsigned long size, int growth)
+{
+ struct rcu_resize_work *work;
+ unsigned long target_size;
+
+ target_size = resize_target_update(ht, size, growth);
+ /* Store resize_target before read resize_initiated */
+ cmm_smp_mb();
+ if (!CMM_LOAD_SHARED(ht->t.resize_initiated) && size < target_size) {
+ uatomic_inc(&ht->in_progress_resize);
+ cmm_smp_mb(); /* increment resize count before load destroy */
+ if (CMM_LOAD_SHARED(ht->in_progress_destroy)) {
+ uatomic_dec(&ht->in_progress_resize);
+ return;
+ }
+ work = malloc(sizeof(*work));
+ work->ht = ht;
+ ht->cds_lfht_call_rcu(&work->head, do_resize_cb);
+ CMM_STORE_SHARED(ht->t.resize_initiated, 1);
+ }
+}
+
+static
+void cds_lfht_resize_lazy_count(struct cds_lfht *ht, unsigned long size,
+ unsigned long count)
+{
+ struct rcu_resize_work *work;
+
+ if (!(ht->flags & CDS_LFHT_AUTO_RESIZE))
+ return;
+ resize_target_update_count(ht, count);
+ /* Store resize_target before read resize_initiated */
+ cmm_smp_mb();
+ if (!CMM_LOAD_SHARED(ht->t.resize_initiated)) {
+ uatomic_inc(&ht->in_progress_resize);
+ cmm_smp_mb(); /* increment resize count before load destroy */
+ if (CMM_LOAD_SHARED(ht->in_progress_destroy)) {
+ uatomic_dec(&ht->in_progress_resize);
+ return;
+ }
+ work = malloc(sizeof(*work));
+ work->ht = ht;
+ ht->cds_lfht_call_rcu(&work->head, do_resize_cb);
+ CMM_STORE_SHARED(ht->t.resize_initiated, 1);
+ }
+}
--- /dev/null
+#ifndef _URCU_RCULFHASH_H
+#define _URCU_RCULFHASH_H
+
+/*
+ * urcu/rculfhash.h
+ *
+ * Userspace RCU library - Lock-Free RCU Hash Table
+ *
+ * Copyright 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Include this file _after_ including your URCU flavor.
+ */
+
+#include <stdint.h>
+#include <urcu-call-rcu.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * struct cds_lfht_node and struct _cds_lfht_node should be aligned on
+ * 4-bytes boundaries because the two lower bits are used as flags.
+ */
+
+/*
+ * _cds_lfht_node: Contains the internal pointers and reverse-hash
+ * value required for lookup and traversal of the hash table.
+ */
+struct _cds_lfht_node {
+ struct cds_lfht_node *next; /* ptr | DUMMY_FLAG | REMOVED_FLAG */
+ unsigned long reverse_hash;
+} __attribute__((aligned(4)));
+
+/*
+ * cds_lfht_node: Contains the full key and length required to check for
+ * an actual match, and also contains an rcu_head structure that is used
+ * by RCU to track a node through a given RCU grace period. There is an
+ * instance of _cds_lfht_node enclosed as a field within each
+ * _cds_lfht_node structure.
+ *
+ * struct cds_lfht_node can be embedded into a structure (as a field).
+ * caa_container_of() can be used to get the structure from the struct
+ * cds_lfht_node after a lookup.
+ */
+struct cds_lfht_node {
+ /* cache-hot for iteration */
+ struct _cds_lfht_node p; /* needs to be first field */
+ void *key;
+ unsigned int key_len;
+ /* cache-cold for iteration */
+ struct rcu_head head;
+};
+
+/* cds_lfht_iter: Used to track state while traversing a hash chain. */
+struct cds_lfht_iter {
+ struct cds_lfht_node *node, *next;
+};
+
+static inline
+struct cds_lfht_node *cds_lfht_iter_get_node(struct cds_lfht_iter *iter)
+{
+ return iter->node;
+}
+
+struct cds_lfht;
+
+/*
+ * Caution !
+ * Ensure reader and writer threads are registered as urcu readers.
+ */
+
+typedef unsigned long (*cds_lfht_hash_fct)(void *key, size_t length,
+ unsigned long seed);
+typedef unsigned long (*cds_lfht_compare_fct)(void *key1, size_t key1_len,
+ void *key2, size_t key2_len);
+
+/*
+ * cds_lfht_node_init - initialize a hash table node
+ */
+static inline
+void cds_lfht_node_init(struct cds_lfht_node *node, void *key,
+ size_t key_len)
+{
+ node->key = key;
+ node->key_len = key_len;
+}
+
+/*
+ * Hash table creation flags.
+ */
+enum {
+ CDS_LFHT_AUTO_RESIZE = (1U << 0),
+ CDS_LFHT_ACCOUNTING = (1U << 1),
+};
+
+/*
+ * _cds_lfht_new - API used by cds_lfht_new wrapper. Do not use directly.
+ */
+struct cds_lfht *_cds_lfht_new(cds_lfht_hash_fct hash_fct,
+ cds_lfht_compare_fct compare_fct,
+ unsigned long hash_seed,
+ unsigned long init_size,
+ unsigned long min_alloc_size,
+ int flags,
+ void (*cds_lfht_call_rcu)(struct rcu_head *head,
+ void (*func)(struct rcu_head *head)),
+ void (*cds_lfht_synchronize_rcu)(void),
+ void (*cds_lfht_rcu_read_lock)(void),
+ void (*cds_lfht_rcu_read_unlock)(void),
+ void (*cds_lfht_rcu_thread_offline)(void),
+ void (*cds_lfht_rcu_thread_online)(void),
+ void (*cds_lfht_rcu_register_thread)(void),
+ void (*cds_lfht_rcu_unregister_thread)(void),
+ pthread_attr_t *attr);
+
+/*
+ * cds_lfht_new - allocate a hash table.
+ * @hash_fct: the hashing function.
+ * @compare_fct: the key comparison function.
+ * @hash_seed: the seed for hash function.
+ * @init_size: number of nodes to allocate initially. Must be power of two.
+ * @min_alloc_size: the smallest allocation size to use. Must be power of two.
+ * @flags: hash table creation flags (can be combined with bitwise or: '|').
+ * 0: no flags.
+ * CDS_LFHT_AUTO_RESIZE: automatically resize hash table.
+ * @attr: optional resize worker thread attributes. NULL for default.
+ *
+ * Return NULL on error.
+ * Note: the RCU flavor must be already included before the hash table header.
+ *
+ * The programmer is responsible for ensuring that resize operation has a
+ * priority equal to hash table updater threads. It should be performed by
+ * specifying the appropriate priority in the pthread "attr" argument, and,
+ * for CDS_LFHT_AUTO_RESIZE, by ensuring that call_rcu worker threads also have
+ * this priority level. Having lower priority for call_rcu and resize threads
+ * does not pose any correctness issue, but the resize operations could be
+ * starved by updates, thus leading to long hash table bucket chains.
+ * Threads calling this API need to be registered RCU read-side threads.
+ */
+static inline
+struct cds_lfht *cds_lfht_new(cds_lfht_hash_fct hash_fct,
+ cds_lfht_compare_fct compare_fct,
+ unsigned long hash_seed,
+ unsigned long init_size,
+ unsigned long min_alloc_size,
+ int flags,
+ pthread_attr_t *attr)
+{
+ return _cds_lfht_new(hash_fct, compare_fct, hash_seed,
+ init_size, min_alloc_size, flags,
+ call_rcu, synchronize_rcu, rcu_read_lock,
+ rcu_read_unlock, rcu_thread_offline,
+ rcu_thread_online, rcu_register_thread,
+ rcu_unregister_thread, attr);
+}
+
+/*
+ * cds_lfht_destroy - destroy a hash table.
+ * @ht: the hash table to destroy.
+ * @attr: (output) resize worker thread attributes, as received by cds_lfht_new.
+ * The caller will typically want to free this pointer if dynamically
+ * allocated. The attr point can be NULL if the caller does not
+ * need to be informed of the value passed to cds_lfht_new().
+ *
+ * Return 0 on success, negative error value on error.
+ * Threads calling this API need to be registered RCU read-side threads.
+ */
+int cds_lfht_destroy(struct cds_lfht *ht, pthread_attr_t **attr);
+
+/*
+ * cds_lfht_count_nodes - count the number of nodes in the hash table.
+ * @ht: the hash table.
+ * @split_count_before: Sample the node count split-counter before traversal.
+ * @count: Traverse the hash table, count the number of nodes observed.
+ * @removed: Number of logically removed nodes observed during traversal.
+ * @split_count_after: Sample the node count split-counter after traversal.
+ * Call with rcu_read_lock held.
+ * Threads calling this API need to be registered RCU read-side threads.
+ */
+void cds_lfht_count_nodes(struct cds_lfht *ht,
+ long *split_count_before,
+ unsigned long *count,
+ unsigned long *removed,
+ long *split_count_after);
+
+/*
+ * cds_lfht_lookup - lookup a node by key.
+ *
+ * Output in "*iter". *iter->node set to NULL if not found.
+ * Call with rcu_read_lock held.
+ * Threads calling this API need to be registered RCU read-side threads.
+ */
+void cds_lfht_lookup(struct cds_lfht *ht, void *key, size_t key_len,
+ struct cds_lfht_iter *iter);
+
+/*
+ * cds_lfht_next_duplicate - get the next item with same key (after a lookup).
+ *
+ * Uses an iterator initialized by a lookup.
+ * Sets *iter-node to the following node with same key.
+ * Sets *iter->node to NULL if no following node exists with same key.
+ * RCU read-side lock must be held across cds_lfht_lookup and
+ * cds_lfht_next calls, and also between cds_lfht_next calls using the
+ * node returned by a previous cds_lfht_next.
+ * Call with rcu_read_lock held.
+ * Threads calling this API need to be registered RCU read-side threads.
+ */
+void cds_lfht_next_duplicate(struct cds_lfht *ht, struct cds_lfht_iter *iter);
+
+/*
+ * cds_lfht_first - get the first node in the table.
+ *
+ * Output in "*iter". *iter->node set to NULL if table is empty.
+ * Call with rcu_read_lock held.
+ * Threads calling this API need to be registered RCU read-side threads.
+ */
+void cds_lfht_first(struct cds_lfht *ht, struct cds_lfht_iter *iter);
+
+/*
+ * cds_lfht_next - get the next node in the table.
+ *
+ * Input/Output in "*iter". *iter->node set to NULL if *iter was
+ * pointing to the last table node.
+ * Call with rcu_read_lock held.
+ * Threads calling this API need to be registered RCU read-side threads.
+ */
+void cds_lfht_next(struct cds_lfht *ht, struct cds_lfht_iter *iter);
+
+/*
+ * cds_lfht_add - add a node to the hash table.
+ *
+ * This function supports adding redundant keys into the table.
+ * Call with rcu_read_lock held.
+ * Threads calling this API need to be registered RCU read-side threads.
+ */
+void cds_lfht_add(struct cds_lfht *ht, struct cds_lfht_node *node);
+
+/*
+ * cds_lfht_add_unique - add a node to hash table, if key is not present.
+ *
+ * Return the node added upon success.
+ * Return the unique node already present upon failure. If
+ * cds_lfht_add_unique fails, the node passed as parameter should be
+ * freed by the caller.
+ * Call with rcu_read_lock held.
+ * Threads calling this API need to be registered RCU read-side threads.
+ *
+ * The semantic of this function is that if only this function is used
+ * to add keys into the table, no duplicated keys should ever be
+ * observable in the table. The same guarantee apply for combination of
+ * add_unique and add_replace (see below).
+ */
+struct cds_lfht_node *cds_lfht_add_unique(struct cds_lfht *ht,
+ struct cds_lfht_node *node);
+
+/*
+ * cds_lfht_add_replace - replace or add a node within hash table.
+ *
+ * Return the node replaced upon success. If no node matching the key
+ * was present, return NULL, which also means the operation succeeded.
+ * This replacement operation should never fail.
+ * Call with rcu_read_lock held.
+ * Threads calling this API need to be registered RCU read-side threads.
+ * After successful replacement, a grace period must be waited for before
+ * freeing the memory reserved for the returned node.
+ *
+ * The semantic of replacement vs lookups is the following: if lookups
+ * are performed between a key unique insertion and its removal, we
+ * guarantee that the lookups and get next will always find exactly one
+ * instance of the key if it is replaced concurrently with the lookups.
+ *
+ * Providing this semantic allows us to ensure that replacement-only
+ * schemes will never generate duplicated keys. It also allows us to
+ * guarantee that a combination of add_replace and add_unique updates
+ * will never generate duplicated keys.
+ */
+struct cds_lfht_node *cds_lfht_add_replace(struct cds_lfht *ht,
+ struct cds_lfht_node *node);
+
+/*
+ * cds_lfht_replace - replace a node pointer to by iter within hash table.
+ *
+ * Return 0 if replacement is successful, negative value otherwise.
+ * Replacing a NULL old node or an already removed node will fail with a
+ * negative value.
+ * Old node can be looked up with cds_lfht_lookup and cds_lfht_next.
+ * RCU read-side lock must be held between lookup and replacement.
+ * Call with rcu_read_lock held.
+ * Threads calling this API need to be registered RCU read-side threads.
+ * After successful replacement, a grace period must be waited for before
+ * freeing the memory reserved for the old node (which can be accessed
+ * with cds_lfht_iter_get_node).
+ *
+ * The semantic of replacement vs lookups is the following: if lookups
+ * are performed between a key unique insertion and its removal, we
+ * guarantee that the lookups and get next will always find exactly one
+ * instance of the key if it is replaced concurrently with the lookups.
+ *
+ * Providing this semantic allows us to ensure that replacement-only
+ * schemes will never generate duplicated keys. It also allows us to
+ * guarantee that a combination of add_replace and add_unique updates
+ * will never generate duplicated keys.
+ */
+int cds_lfht_replace(struct cds_lfht *ht, struct cds_lfht_iter *old_iter,
+ struct cds_lfht_node *new_node);
+
+/*
+ * cds_lfht_del - remove node pointed to by iterator from hash table.
+ *
+ * Return 0 if the node is successfully removed, negative value
+ * otherwise.
+ * Replacing a NULL node or an already removed node will fail with a
+ * negative value.
+ * Node can be looked up with cds_lfht_lookup and cds_lfht_next.
+ * cds_lfht_iter_get_node.
+ * RCU read-side lock must be held between lookup and removal.
+ * Call with rcu_read_lock held.
+ * Threads calling this API need to be registered RCU read-side threads.
+ * After successful removal, a grace period must be waited for before
+ * freeing the memory reserved for old node (which can be accessed with
+ * cds_lfht_iter_get_node).
+ */
+int cds_lfht_del(struct cds_lfht *ht, struct cds_lfht_iter *iter);
+
+/*
+ * cds_lfht_resize - Force a hash table resize
+ * @new_size: update to this hash table size.
+ *
+ * Threads calling this API need to be registered RCU read-side threads.
+ */
+void cds_lfht_resize(struct cds_lfht *ht, unsigned long new_size);
+
+/*
+ * Note: cds_lfht_for_each are safe for element removal during
+ * iteration.
+ */
+#define cds_lfht_for_each(ht, iter, node) \
+ for (cds_lfht_first(ht, iter), \
+ node = cds_lfht_iter_get_node(iter); \
+ node != NULL; \
+ cds_lfht_next(ht, iter), \
+ node = cds_lfht_iter_get_node(iter))
+
+#define cds_lfht_for_each_duplicate(ht, match, hash, key, iter, node) \
+ for (cds_lfht_lookup(ht, match, hash, key, iter), \
+ node = cds_lfht_iter_get_node(iter); \
+ node != NULL; \
+ cds_lfht_next_duplicate(ht, match, key, iter), \
+ node = cds_lfht_iter_get_node(iter))
+
+#define cds_lfht_for_each_entry(ht, iter, pos, member) \
+ for (cds_lfht_first(ht, iter), \
+ pos = caa_container_of(cds_lfht_iter_get_node(iter), \
+ typeof(*(pos)), member); \
+ &(pos)->member != NULL; \
+ cds_lfht_next(ht, iter), \
+ pos = caa_container_of(cds_lfht_iter_get_node(iter), \
+ typeof(*(pos)), member))
+
+#define cds_lfht_for_each_entry_duplicate(ht, match, hash, key, \
+ iter, pos, member) \
+for (cds_lfht_lookup(ht, match, hash, key, iter), \
+ pos = caa_container_of(cds_lfht_iter_get_node(iter), \
+ typeof(*(pos)), member); \
+ &(pos)->member != NULL; \
+ cds_lfht_next_duplicate(ht, match, key, iter), \
+ pos = caa_container_of(cds_lfht_iter_get_node(iter), \
+ typeof(*(pos)), member))
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _URCU_RCULFHASH_H */
AC_CONFIG_FILES([
Makefile
include/Makefile
+ common/Makefile
libkernelctl/Makefile
liblttng-consumer/Makefile
liblttng-kconsumer/Makefile
+++ /dev/null
-/*
- * Copyright (C) - Bob Jenkins, May 2006, Public Domain.
- * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
- * Copyright (C) 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * These are functions for producing 32-bit hashes for hash table lookup.
- * hashword(), hashlittle(), hashlittle2(), hashbig(), mix(), and final() are
- * externally useful functions. Routines to test the hash are included if
- * SELF_TEST is defined. You can use this free for any purpose. It's in the
- * public domain. It has no warranty.
- *
- * You probably want to use hashlittle(). hashlittle() and hashbig() hash byte
- * arrays. hashlittle() is is faster than hashbig() on little-endian machines.
- * Intel and AMD are little-endian machines. On second thought, you probably
- * want hashlittle2(), which is identical to hashlittle() except it returns two
- * 32-bit hashes for the price of one. You could implement hashbig2() if you
- * wanted but I haven't bothered here.
- *
- * If you want to find a hash of, say, exactly 7 integers, do
- * a = i1; b = i2; c = i3;
- * mix(a,b,c);
- * a += i4; b += i5; c += i6;
- * mix(a,b,c);
- * a += i7;
- * final(a,b,c);
- * then use c as the hash value. If you have a variable length array of
- * 4-byte integers to hash, use hashword(). If you have a byte array (like
- * a character string), use hashlittle(). If you have several byte arrays, or
- * a mix of things, see the comments above hashlittle().
- *
- * Why is this so big? I read 12 bytes at a time into 3 4-byte integers, then
- * mix those integers. This is fast (you can do a lot more thorough mixing
- * with 12*3 instructions on 3 integers than you can with 3 instructions on 1
- * byte), but shoehorning those bytes into integers efficiently is messy.
- */
-
-#include <stdio.h> /* defines printf for tests */
-#include <time.h> /* defines time_t for timings in the test */
-#include <stdint.h> /* defines uint32_t etc */
-#include <sys/param.h> /* attempt to define endianness */
-#include <endian.h> /* attempt to define endianness */
-#include <string.h>
-#include <assert.h>
-#include <urcu/compiler.h>
-
-/*
- * My best guess at if you are big-endian or little-endian. This may
- * need adjustment.
- */
-#if (defined(__BYTE_ORDER) && defined(__LITTLE_ENDIAN) && \
- __BYTE_ORDER == __LITTLE_ENDIAN) || \
- (defined(i386) || defined(__i386__) || defined(__i486__) || \
- defined(__i586__) || defined(__i686__) || defined(vax) || defined(MIPSEL))
-# define HASH_LITTLE_ENDIAN 1
-# define HASH_BIG_ENDIAN 0
-#elif (defined(__BYTE_ORDER) && defined(__BIG_ENDIAN) && \
- __BYTE_ORDER == __BIG_ENDIAN) || \
- (defined(sparc) || defined(POWERPC) || defined(mc68000) || defined(sel))
-# define HASH_LITTLE_ENDIAN 0
-# define HASH_BIG_ENDIAN 1
-#else
-# define HASH_LITTLE_ENDIAN 0
-# define HASH_BIG_ENDIAN 0
-#endif
-
-#define hashsize(n) ((uint32_t)1<<(n))
-#define hashmask(n) (hashsize(n)-1)
-#define rot(x,k) (((x)<<(k)) | ((x)>>(32-(k))))
-
-/*
- * mix -- mix 3 32-bit values reversibly.
- *
- * This is reversible, so any information in (a,b,c) before mix() is
- * still in (a,b,c) after mix().
- *
- * If four pairs of (a,b,c) inputs are run through mix(), or through
- * mix() in reverse, there are at least 32 bits of the output that
- * are sometimes the same for one pair and different for another pair.
- * This was tested for:
- * * pairs that differed by one bit, by two bits, in any combination
- * of top bits of (a,b,c), or in any combination of bottom bits of
- * (a,b,c).
- * * "differ" is defined as +, -, ^, or ~^. For + and -, I transformed
- * the output delta to a Gray code (a^(a>>1)) so a string of 1's (as
- * is commonly produced by subtraction) look like a single 1-bit
- * difference.
- * * the base values were pseudorandom, all zero but one bit set, or
- * all zero plus a counter that starts at zero.
- *
- * Some k values for my "a-=c; a^=rot(c,k); c+=b;" arrangement that
- * satisfy this are
- * 4 6 8 16 19 4
- * 9 15 3 18 27 15
- * 14 9 3 7 17 3
- * Well, "9 15 3 18 27 15" didn't quite get 32 bits diffing
- * for "differ" defined as + with a one-bit base and a two-bit delta. I
- * used http://burtleburtle.net/bob/hash/avalanche.html to choose
- * the operations, constants, and arrangements of the variables.
- *
- * This does not achieve avalanche. There are input bits of (a,b,c)
- * that fail to affect some output bits of (a,b,c), especially of a. The
- * most thoroughly mixed value is c, but it doesn't really even achieve
- * avalanche in c.
- *
- * This allows some parallelism. Read-after-writes are good at doubling
- * the number of bits affected, so the goal of mixing pulls in the opposite
- * direction as the goal of parallelism. I did what I could. Rotates
- * seem to cost as much as shifts on every machine I could lay my hands
- * on, and rotates are much kinder to the top and bottom bits, so I used
- * rotates.
- */
-#define mix(a,b,c) \
-{ \
- a -= c; a ^= rot(c, 4); c += b; \
- b -= a; b ^= rot(a, 6); a += c; \
- c -= b; c ^= rot(b, 8); b += a; \
- a -= c; a ^= rot(c,16); c += b; \
- b -= a; b ^= rot(a,19); a += c; \
- c -= b; c ^= rot(b, 4); b += a; \
-}
-
-/*
- * final -- final mixing of 3 32-bit values (a,b,c) into c
- *
- * Pairs of (a,b,c) values differing in only a few bits will usually
- * produce values of c that look totally different. This was tested for
- * * pairs that differed by one bit, by two bits, in any combination
- * of top bits of (a,b,c), or in any combination of bottom bits of
- * (a,b,c).
- * * "differ" is defined as +, -, ^, or ~^. For + and -, I transformed
- * the output delta to a Gray code (a^(a>>1)) so a string of 1's (as
- * is commonly produced by subtraction) look like a single 1-bit
- * difference.
- * * the base values were pseudorandom, all zero but one bit set, or
- * all zero plus a counter that starts at zero.
- *
- * These constants passed:
- * 14 11 25 16 4 14 24
- * 12 14 25 16 4 14 24
- * and these came close:
- * 4 8 15 26 3 22 24
- * 10 8 15 26 3 22 24
- * 11 8 15 26 3 22 24
- */
-#define final(a,b,c) \
-{ \
- c ^= b; c -= rot(b,14); \
- a ^= c; a -= rot(c,11); \
- b ^= a; b -= rot(a,25); \
- c ^= b; c -= rot(b,16); \
- a ^= c; a -= rot(c,4); \
- b ^= a; b -= rot(a,14); \
- c ^= b; c -= rot(b,24); \
-}
-
-static __attribute__((unused))
-uint32_t hashword(
- const uint32_t *k, /* the key, an array of uint32_t values */
- size_t length, /* the length of the key, in uint32_ts */
- uint32_t initval) /* the previous hash, or an arbitrary value */
-{
- uint32_t a, b, c;
-
- /* Set up the internal state */
- a = b = c = 0xdeadbeef + (((uint32_t) length) << 2) + initval;
-
- /*----------------------------------------- handle most of the key */
- while (length > 3) {
- a += k[0];
- b += k[1];
- c += k[2];
- mix(a, b, c);
- length -= 3;
- k += 3;
- }
-
- /*----------------------------------- handle the last 3 uint32_t's */
- switch (length) { /* all the case statements fall through */
- case 3: c += k[2];
- case 2: b += k[1];
- case 1: a += k[0];
- final(a, b, c);
- case 0: /* case 0: nothing left to add */
- break;
- }
- /*---------------------------------------------- report the result */
- return c;
-}
-
-
-/*
- * hashword2() -- same as hashword(), but take two seeds and return two 32-bit
- * values. pc and pb must both be nonnull, and *pc and *pb must both be
- * initialized with seeds. If you pass in (*pb)==0, the output (*pc) will be
- * the same as the return value from hashword().
- */
-static __attribute__((unused))
-void hashword2(const uint32_t *k, size_t length,
- uint32_t *pc, uint32_t *pb)
-{
- uint32_t a, b, c;
-
- /* Set up the internal state */
- a = b = c = 0xdeadbeef + ((uint32_t) (length << 2)) + *pc;
- c += *pb;
-
- while (length > 3) {
- a += k[0];
- b += k[1];
- c += k[2];
- mix(a, b, c);
- length -= 3;
- k += 3;
- }
-
- switch (length) {
- case 3 :
- c += k[2];
- case 2 :
- b += k[1];
- case 1 :
- a += k[0];
- final(a, b, c);
- case 0: /* case 0: nothing left to add */
- break;
- }
-
- *pc = c;
- *pb = b;
-}
-
-/*
- * hashlittle() -- hash a variable-length key into a 32-bit value
- * k : the key (the unaligned variable-length array of bytes)
- * length : the length of the key, counting by bytes
- * initval : can be any 4-byte value
- * Returns a 32-bit value. Every bit of the key affects every bit of
- * the return value. Two keys differing by one or two bits will have
- * totally different hash values.
- *
- * The best hash table sizes are powers of 2. There is no need to do
- * mod a prime (mod is sooo slow!). If you need less than 32 bits,
- * use a bitmask. For example, if you need only 10 bits, do
- * h = (h & hashmask(10));
- * In which case, the hash table should have hashsize(10) elements.
- *
- * If you are hashing n strings (uint8_t **)k, do it like this:
- * for (i=0, h=0; i<n; ++i) h = hashlittle( k[i], len[i], h);
- *
- * By Bob Jenkins, 2006. bob_jenkins@burtleburtle.net. You may use this
- * code any way you wish, private, educational, or commercial. It's free.
- *
- * Use for hash table lookup, or anything where one collision in 2^^32 is
- * acceptable. Do NOT use for cryptographic purposes.
- */
-
-static uint32_t hashlittle(const void *key, size_t length, uint32_t initval)
-{
- uint32_t a,b,c;
- union {
- const void *ptr;
- size_t i;
- } u; /* needed for Mac Powerbook G4 */
-
- /* Set up the internal state */
- a = b = c = 0xdeadbeef + ((uint32_t)length) + initval;
-
- u.ptr = key;
- if (HASH_LITTLE_ENDIAN && ((u.i & 0x3) == 0)) {
- const uint32_t *k = (const uint32_t *)key; /* read 32-bit chunks */
-
- /*------ all but last block: aligned reads and affect 32 bits of (a,b,c) */
- while (length > 12) {
- a += k[0];
- b += k[1];
- c += k[2];
- mix(a,b,c);
- length -= 12;
- k += 3;
- }
-
- /*
- * "k[2]&0xffffff" actually reads beyond the end of the string, but
- * then masks off the part it's not allowed to read. Because the
- * string is aligned, the masked-off tail is in the same word as the
- * rest of the string. Every machine with memory protection I've seen
- * does it on word boundaries, so is OK with this. But VALGRIND will
- * still catch it and complain. The masking trick does make the hash
- * noticably faster for short strings (like English words).
- */
-#ifndef VALGRIND
-
- switch (length) {
- case 12: c+=k[2]; b+=k[1]; a+=k[0]; break;
- case 11: c+=k[2]&0xffffff; b+=k[1]; a+=k[0]; break;
- case 10: c+=k[2]&0xffff; b+=k[1]; a+=k[0]; break;
- case 9 : c+=k[2]&0xff; b+=k[1]; a+=k[0]; break;
- case 8 : b+=k[1]; a+=k[0]; break;
- case 7 : b+=k[1]&0xffffff; a+=k[0]; break;
- case 6 : b+=k[1]&0xffff; a+=k[0]; break;
- case 5 : b+=k[1]&0xff; a+=k[0]; break;
- case 4 : a+=k[0]; break;
- case 3 : a+=k[0]&0xffffff; break;
- case 2 : a+=k[0]&0xffff; break;
- case 1 : a+=k[0]&0xff; break;
- case 0 : return c; /* zero length strings require no mixing */
- }
-#else /* make valgrind happy */
- const uint8_t *k8;
-
- k8 = (const uint8_t *)k;
- switch (length) {
- case 12: c+=k[2]; b+=k[1]; a+=k[0]; break;
- case 11: c+=((uint32_t)k8[10])<<16; /* fall through */
- case 10: c+=((uint32_t)k8[9])<<8; /* fall through */
- case 9 : c+=k8[8]; /* fall through */
- case 8 : b+=k[1]; a+=k[0]; break;
- case 7 : b+=((uint32_t)k8[6])<<16; /* fall through */
- case 6 : b+=((uint32_t)k8[5])<<8; /* fall through */
- case 5 : b+=k8[4]; /* fall through */
- case 4 : a+=k[0]; break;
- case 3 : a+=((uint32_t)k8[2])<<16; /* fall through */
- case 2 : a+=((uint32_t)k8[1])<<8; /* fall through */
- case 1 : a+=k8[0]; break;
- case 0 : return c;
- }
-#endif /* !valgrind */
- } else if (HASH_LITTLE_ENDIAN && ((u.i & 0x1) == 0)) {
- const uint16_t *k = (const uint16_t *)key; /* read 16-bit chunks */
- const uint8_t *k8;
-
- /*--------------- all but last block: aligned reads and different mixing */
- while (length > 12) {
- a += k[0] + (((uint32_t)k[1])<<16);
- b += k[2] + (((uint32_t)k[3])<<16);
- c += k[4] + (((uint32_t)k[5])<<16);
- mix(a,b,c);
- length -= 12;
- k += 6;
- }
-
- k8 = (const uint8_t *)k;
- switch (length) {
- case 12:
- c+=k[4]+(((uint32_t)k[5])<<16);
- b+=k[2]+(((uint32_t)k[3])<<16);
- a+=k[0]+(((uint32_t)k[1])<<16);
- break;
- case 11:
- c+=((uint32_t)k8[10])<<16; /* fall through */
- case 10:
- c+=k[4];
- b+=k[2]+(((uint32_t)k[3])<<16);
- a+=k[0]+(((uint32_t)k[1])<<16);
- break;
- case 9:
- c+=k8[8]; /* fall through */
- case 8:
- b+=k[2]+(((uint32_t)k[3])<<16);
- a+=k[0]+(((uint32_t)k[1])<<16);
- break;
- case 7:
- b+=((uint32_t)k8[6])<<16; /* fall through */
- case 6:
- b+=k[2];
- a+=k[0]+(((uint32_t)k[1])<<16);
- break;
- case 5:
- b+=k8[4]; /* fall through */
- case 4:
- a+=k[0]+(((uint32_t)k[1])<<16);
- break;
- case 3:
- a+=((uint32_t)k8[2])<<16; /* fall through */
- case 2:
- a+=k[0];
- break;
- case 1:
- a+=k8[0];
- break;
- case 0:
- return c; /* zero length requires no mixing */
- }
-
- } else { /* need to read the key one byte at a time */
- const uint8_t *k = (const uint8_t *)key;
-
- while (length > 12) {
- a += k[0];
- a += ((uint32_t)k[1])<<8;
- a += ((uint32_t)k[2])<<16;
- a += ((uint32_t)k[3])<<24;
- b += k[4];
- b += ((uint32_t)k[5])<<8;
- b += ((uint32_t)k[6])<<16;
- b += ((uint32_t)k[7])<<24;
- c += k[8];
- c += ((uint32_t)k[9])<<8;
- c += ((uint32_t)k[10])<<16;
- c += ((uint32_t)k[11])<<24;
- mix(a,b,c);
- length -= 12;
- k += 12;
- }
-
- switch(length) { /* all the case statements fall through */
- case 12: c+=((uint32_t)k[11])<<24;
- case 11: c+=((uint32_t)k[10])<<16;
- case 10: c+=((uint32_t)k[9])<<8;
- case 9: c+=k[8];
- case 8: b+=((uint32_t)k[7])<<24;
- case 7: b+=((uint32_t)k[6])<<16;
- case 6: b+=((uint32_t)k[5])<<8;
- case 5: b+=k[4];
- case 4: a+=((uint32_t)k[3])<<24;
- case 3: a+=((uint32_t)k[2])<<16;
- case 2: a+=((uint32_t)k[1])<<8;
- case 1:
- a+=k[0];
- break;
- case 0:
- return c;
- }
- }
-
- final(a,b,c);
- return c;
-}
-
-#if (CAA_BITS_PER_LONG == 64)
-/*
- * Hash function for number value.
- */
-unsigned long hash_key(void *_key, size_t length, unsigned long seed)
-{
- union {
- uint64_t v64;
- uint32_t v32[2];
- } v;
- union {
- uint64_t v64;
- uint32_t v32[2];
- } key;
-
- assert(length == sizeof(unsigned long));
- v.v64 = (uint64_t) seed;
- key.v64 = (uint64_t) _key;
- hashword2(key.v32, 2, &v.v32[0], &v.v32[1]);
- return v.v64;
-}
-#else
-/*
- * Hash function for number value.
- */
-unsigned long hash_key(void *_key, size_t length, unsigned long seed)
-{
- uint32_t key = (uint32_t) _key;
-
- assert(length == sizeof(uint32_t));
- return hashword(&key, 1, seed);
-}
-#endif
-
-/*
- * Hash function for string.
- */
-unsigned long hash_key_str(void *key, size_t length, unsigned long seed)
-{
- return hashlittle(key, length, seed);
-}
-
-/*
- * Hash function compare for number value.
- */
-unsigned long hash_compare_key(void *key1, size_t key1_len,
- void *key2, size_t key2_len)
-{
- if (key1_len != key2_len) {
- return -1;
- }
-
- if (key1 == key2) {
- return 0;
- }
-
- return 1;
-}
-
-/*
- * Hash compare function for string.
- */
-unsigned long hash_compare_key_str(void *key1, size_t key1_len,
- void *key2, size_t key2_len)
-{
- if (key1_len != key2_len) {
- return -1;
- }
-
- if (strncmp(key1, key2, key1_len) == 0) {
- return 0;
- }
-
- return 1;
-}
+++ /dev/null
-/*
- * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the Free
- * Software Foundation; only version 2 of the License.
- *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
- * Place - Suite 330, Boston, MA 02111-1307, USA.
- */
-
-#ifndef _LTT_HASH_H
-#define _LTT_HASH_H
-
-unsigned long hash_key(void *_key, size_t length, unsigned long seed);
-
-unsigned long hash_key_str(void *_key, size_t length, unsigned long seed);
-
-unsigned long hash_compare_key(void *key1, size_t key1_len,
- void *key2, size_t key2_len);
-
-unsigned long hash_compare_key_str(void *key1, size_t key1_len,
- void *key2, size_t key2_len);
-
-#endif /* _LTT_HASH_H */
+++ /dev/null
-/*
- * rculfhash.c
- *
- * Userspace RCU library - Lock-Free Resizable RCU Hash Table
- *
- * Copyright 2010-2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-/*
- * Based on the following articles:
- * - Ori Shalev and Nir Shavit. Split-ordered lists: Lock-free
- * extensible hash tables. J. ACM 53, 3 (May 2006), 379-405.
- * - Michael, M. M. High performance dynamic lock-free hash tables
- * and list-based sets. In Proceedings of the fourteenth annual ACM
- * symposium on Parallel algorithms and architectures, ACM Press,
- * (2002), 73-82.
- *
- * Some specificities of this Lock-Free Resizable RCU Hash Table
- * implementation:
- *
- * - RCU read-side critical section allows readers to perform hash
- * table lookups and use the returned objects safely by delaying
- * memory reclaim of a grace period.
- * - Add and remove operations are lock-free, and do not need to
- * allocate memory. They need to be executed within RCU read-side
- * critical section to ensure the objects they read are valid and to
- * deal with the cmpxchg ABA problem.
- * - add and add_unique operations are supported. add_unique checks if
- * the node key already exists in the hash table. It ensures no key
- * duplicata exists.
- * - The resize operation executes concurrently with add/remove/lookup.
- * - Hash table nodes are contained within a split-ordered list. This
- * list is ordered by incrementing reversed-bits-hash value.
- * - An index of dummy nodes is kept. These dummy nodes are the hash
- * table "buckets", and they are also chained together in the
- * split-ordered list, which allows recursive expansion.
- * - The resize operation for small tables only allows expanding the hash table.
- * It is triggered automatically by detecting long chains in the add
- * operation.
- * - The resize operation for larger tables (and available through an
- * API) allows both expanding and shrinking the hash table.
- * - Split-counters are used to keep track of the number of
- * nodes within the hash table for automatic resize triggering.
- * - Resize operation initiated by long chain detection is executed by a
- * call_rcu thread, which keeps lock-freedom of add and remove.
- * - Resize operations are protected by a mutex.
- * - The removal operation is split in two parts: first, a "removed"
- * flag is set in the next pointer within the node to remove. Then,
- * a "garbage collection" is performed in the bucket containing the
- * removed node (from the start of the bucket up to the removed node).
- * All encountered nodes with "removed" flag set in their next
- * pointers are removed from the linked-list. If the cmpxchg used for
- * removal fails (due to concurrent garbage-collection or concurrent
- * add), we retry from the beginning of the bucket. This ensures that
- * the node with "removed" flag set is removed from the hash table
- * (not visible to lookups anymore) before the RCU read-side critical
- * section held across removal ends. Furthermore, this ensures that
- * the node with "removed" flag set is removed from the linked-list
- * before its memory is reclaimed. Only the thread which removal
- * successfully set the "removed" flag (with a cmpxchg) into a node's
- * next pointer is considered to have succeeded its removal (and thus
- * owns the node to reclaim). Because we garbage-collect starting from
- * an invariant node (the start-of-bucket dummy node) up to the
- * "removed" node (or find a reverse-hash that is higher), we are sure
- * that a successful traversal of the chain leads to a chain that is
- * present in the linked-list (the start node is never removed) and
- * that is does not contain the "removed" node anymore, even if
- * concurrent delete/add operations are changing the structure of the
- * list concurrently.
- * - The add operation performs gargage collection of buckets if it
- * encounters nodes with removed flag set in the bucket where it wants
- * to add its new node. This ensures lock-freedom of add operation by
- * helping the remover unlink nodes from the list rather than to wait
- * for it do to so.
- * - A RCU "order table" indexed by log2(hash index) is copied and
- * expanded by the resize operation. This order table allows finding
- * the "dummy node" tables.
- * - There is one dummy node table per hash index order. The size of
- * each dummy node table is half the number of hashes contained in
- * this order (except for order 0).
- * - synchronzie_rcu is used to garbage-collect the old dummy node table.
- * - The per-order dummy node tables contain a compact version of the
- * hash table nodes. These tables are invariant after they are
- * populated into the hash table.
- *
- * Dummy node tables:
- *
- * hash table hash table the last all dummy node tables
- * order size dummy node 0 1 2 3 4 5 6(index)
- * table size
- * 0 1 1 1
- * 1 2 1 1 1
- * 2 4 2 1 1 2
- * 3 8 4 1 1 2 4
- * 4 16 8 1 1 2 4 8
- * 5 32 16 1 1 2 4 8 16
- * 6 64 32 1 1 2 4 8 16 32
- *
- * When growing/shrinking, we only focus on the last dummy node table
- * which size is (!order ? 1 : (1 << (order -1))).
- *
- * Example for growing/shrinking:
- * grow hash table from order 5 to 6: init the index=6 dummy node table
- * shrink hash table from order 6 to 5: fini the index=6 dummy node table
- *
- * A bit of ascii art explanation:
- *
- * Order index is the off-by-one compare to the actual power of 2 because
- * we use index 0 to deal with the 0 special-case.
- *
- * This shows the nodes for a small table ordered by reversed bits:
- *
- * bits reverse
- * 0 000 000
- * 4 100 001
- * 2 010 010
- * 6 110 011
- * 1 001 100
- * 5 101 101
- * 3 011 110
- * 7 111 111
- *
- * This shows the nodes in order of non-reversed bits, linked by
- * reversed-bit order.
- *
- * order bits reverse
- * 0 0 000 000
- * 1 | 1 001 100 <-
- * 2 | | 2 010 010 <- |
- * | | | 3 011 110 | <- |
- * 3 -> | | | 4 100 001 | |
- * -> | | 5 101 101 |
- * -> | 6 110 011
- * -> 7 111 111
- */
-
-#define _LGPL_SOURCE
-#include <stdlib.h>
-#include <errno.h>
-#include <assert.h>
-#include <stdio.h>
-#include <stdint.h>
-#include <string.h>
-
-#include "config.h"
-#include <urcu.h>
-#include <urcu-call-rcu.h>
-#include <urcu/arch.h>
-#include <urcu/uatomic.h>
-#include <urcu/compiler.h>
-#include <stdio.h>
-#include <pthread.h>
-
-#include "rculfhash.h"
-
-#ifdef DEBUG
-#define dbg_printf(fmt, args...) printf("[debug rculfhash] " fmt, ## args)
-#else
-#define dbg_printf(fmt, args...)
-#endif
-
-/*
- * Split-counters lazily update the global counter each 1024
- * addition/removal. It automatically keeps track of resize required.
- * We use the bucket length as indicator for need to expand for small
- * tables and machines lacking per-cpu data suppport.
- */
-#define COUNT_COMMIT_ORDER 10
-#define DEFAULT_SPLIT_COUNT_MASK 0xFUL
-#define CHAIN_LEN_TARGET 1
-#define CHAIN_LEN_RESIZE_THRESHOLD 3
-
-/*
- * Define the minimum table size.
- */
-#define MIN_TABLE_SIZE 1
-
-#if (CAA_BITS_PER_LONG == 32)
-#define MAX_TABLE_ORDER 32
-#else
-#define MAX_TABLE_ORDER 64
-#endif
-
-/*
- * Minimum number of dummy nodes to touch per thread to parallelize grow/shrink.
- */
-#define MIN_PARTITION_PER_THREAD_ORDER 12
-#define MIN_PARTITION_PER_THREAD (1UL << MIN_PARTITION_PER_THREAD_ORDER)
-
-#ifndef min
-#define min(a, b) ((a) < (b) ? (a) : (b))
-#endif
-
-#ifndef max
-#define max(a, b) ((a) > (b) ? (a) : (b))
-#endif
-
-/*
- * The removed flag needs to be updated atomically with the pointer.
- * It indicates that no node must attach to the node scheduled for
- * removal, and that node garbage collection must be performed.
- * The dummy flag does not require to be updated atomically with the
- * pointer, but it is added as a pointer low bit flag to save space.
- */
-#define REMOVED_FLAG (1UL << 0)
-#define DUMMY_FLAG (1UL << 1)
-#define FLAGS_MASK ((1UL << 2) - 1)
-
-/* Value of the end pointer. Should not interact with flags. */
-#define END_VALUE NULL
-
-/*
- * ht_items_count: Split-counters counting the number of node addition
- * and removal in the table. Only used if the CDS_LFHT_ACCOUNTING flag
- * is set at hash table creation.
- *
- * These are free-running counters, never reset to zero. They count the
- * number of add/remove, and trigger every (1 << COUNT_COMMIT_ORDER)
- * operations to update the global counter. We choose a power-of-2 value
- * for the trigger to deal with 32 or 64-bit overflow of the counter.
- */
-struct ht_items_count {
- unsigned long add, del;
-} __attribute__((aligned(CAA_CACHE_LINE_SIZE)));
-
-/*
- * rcu_level: Contains the per order-index-level dummy node table. The
- * size of each dummy node table is half the number of hashes contained
- * in this order (except for order 0). The minimum allocation size
- * parameter allows combining the dummy node arrays of the lowermost
- * levels to improve cache locality for small index orders.
- */
-struct rcu_level {
- /* Note: manually update allocation length when adding a field */
- struct _cds_lfht_node nodes[0];
-};
-
-/*
- * rcu_table: Contains the size and desired new size if a resize
- * operation is in progress, as well as the statically-sized array of
- * rcu_level pointers.
- */
-struct rcu_table {
- unsigned long size; /* always a power of 2, shared (RCU) */
- unsigned long resize_target;
- int resize_initiated;
- struct rcu_level *tbl[MAX_TABLE_ORDER];
-};
-
-/*
- * cds_lfht: Top-level data structure representing a lock-free hash
- * table. Defined in the implementation file to make it be an opaque
- * cookie to users.
- */
-struct cds_lfht {
- struct rcu_table t;
- cds_lfht_hash_fct hash_fct;
- cds_lfht_compare_fct compare_fct;
- unsigned long min_alloc_order;
- unsigned long min_alloc_size;
- unsigned long hash_seed;
- int flags;
- /*
- * We need to put the work threads offline (QSBR) when taking this
- * mutex, because we use synchronize_rcu within this mutex critical
- * section, which waits on read-side critical sections, and could
- * therefore cause grace-period deadlock if we hold off RCU G.P.
- * completion.
- */
- pthread_mutex_t resize_mutex; /* resize mutex: add/del mutex */
- unsigned int in_progress_resize, in_progress_destroy;
- void (*cds_lfht_call_rcu)(struct rcu_head *head,
- void (*func)(struct rcu_head *head));
- void (*cds_lfht_synchronize_rcu)(void);
- void (*cds_lfht_rcu_read_lock)(void);
- void (*cds_lfht_rcu_read_unlock)(void);
- void (*cds_lfht_rcu_thread_offline)(void);
- void (*cds_lfht_rcu_thread_online)(void);
- void (*cds_lfht_rcu_register_thread)(void);
- void (*cds_lfht_rcu_unregister_thread)(void);
- pthread_attr_t *resize_attr; /* Resize threads attributes */
- long count; /* global approximate item count */
- struct ht_items_count *split_count; /* split item count */
-};
-
-/*
- * rcu_resize_work: Contains arguments passed to RCU worker thread
- * responsible for performing lazy resize.
- */
-struct rcu_resize_work {
- struct rcu_head head;
- struct cds_lfht *ht;
-};
-
-/*
- * partition_resize_work: Contains arguments passed to worker threads
- * executing the hash table resize on partitions of the hash table
- * assigned to each processor's worker thread.
- */
-struct partition_resize_work {
- pthread_t thread_id;
- struct cds_lfht *ht;
- unsigned long i, start, len;
- void (*fct)(struct cds_lfht *ht, unsigned long i,
- unsigned long start, unsigned long len);
-};
-
-static
-void _cds_lfht_add(struct cds_lfht *ht,
- unsigned long size,
- struct cds_lfht_node *node,
- struct cds_lfht_iter *unique_ret,
- int dummy);
-
-/*
- * Algorithm to reverse bits in a word by lookup table, extended to
- * 64-bit words.
- * Source:
- * http://graphics.stanford.edu/~seander/bithacks.html#BitReverseTable
- * Originally from Public Domain.
- */
-
-static const uint8_t BitReverseTable256[256] =
-{
-#define R2(n) (n), (n) + 2*64, (n) + 1*64, (n) + 3*64
-#define R4(n) R2(n), R2((n) + 2*16), R2((n) + 1*16), R2((n) + 3*16)
-#define R6(n) R4(n), R4((n) + 2*4 ), R4((n) + 1*4 ), R4((n) + 3*4 )
- R6(0), R6(2), R6(1), R6(3)
-};
-#undef R2
-#undef R4
-#undef R6
-
-static
-uint8_t bit_reverse_u8(uint8_t v)
-{
- return BitReverseTable256[v];
-}
-
-static __attribute__((unused))
-uint32_t bit_reverse_u32(uint32_t v)
-{
- return ((uint32_t) bit_reverse_u8(v) << 24) |
- ((uint32_t) bit_reverse_u8(v >> 8) << 16) |
- ((uint32_t) bit_reverse_u8(v >> 16) << 8) |
- ((uint32_t) bit_reverse_u8(v >> 24));
-}
-
-static __attribute__((unused))
-uint64_t bit_reverse_u64(uint64_t v)
-{
- return ((uint64_t) bit_reverse_u8(v) << 56) |
- ((uint64_t) bit_reverse_u8(v >> 8) << 48) |
- ((uint64_t) bit_reverse_u8(v >> 16) << 40) |
- ((uint64_t) bit_reverse_u8(v >> 24) << 32) |
- ((uint64_t) bit_reverse_u8(v >> 32) << 24) |
- ((uint64_t) bit_reverse_u8(v >> 40) << 16) |
- ((uint64_t) bit_reverse_u8(v >> 48) << 8) |
- ((uint64_t) bit_reverse_u8(v >> 56));
-}
-
-static
-unsigned long bit_reverse_ulong(unsigned long v)
-{
-#if (CAA_BITS_PER_LONG == 32)
- return bit_reverse_u32(v);
-#else
- return bit_reverse_u64(v);
-#endif
-}
-
-/*
- * fls: returns the position of the most significant bit.
- * Returns 0 if no bit is set, else returns the position of the most
- * significant bit (from 1 to 32 on 32-bit, from 1 to 64 on 64-bit).
- */
-#if defined(__i386) || defined(__x86_64)
-static inline
-unsigned int fls_u32(uint32_t x)
-{
- int r;
-
- asm("bsrl %1,%0\n\t"
- "jnz 1f\n\t"
- "movl $-1,%0\n\t"
- "1:\n\t"
- : "=r" (r) : "rm" (x));
- return r + 1;
-}
-#define HAS_FLS_U32
-#endif
-
-#if defined(__x86_64)
-static inline
-unsigned int fls_u64(uint64_t x)
-{
- long r;
-
- asm("bsrq %1,%0\n\t"
- "jnz 1f\n\t"
- "movq $-1,%0\n\t"
- "1:\n\t"
- : "=r" (r) : "rm" (x));
- return r + 1;
-}
-#define HAS_FLS_U64
-#endif
-
-#ifndef HAS_FLS_U64
-static __attribute__((unused))
-unsigned int fls_u64(uint64_t x)
-{
- unsigned int r = 64;
-
- if (!x)
- return 0;
-
- if (!(x & 0xFFFFFFFF00000000ULL)) {
- x <<= 32;
- r -= 32;
- }
- if (!(x & 0xFFFF000000000000ULL)) {
- x <<= 16;
- r -= 16;
- }
- if (!(x & 0xFF00000000000000ULL)) {
- x <<= 8;
- r -= 8;
- }
- if (!(x & 0xF000000000000000ULL)) {
- x <<= 4;
- r -= 4;
- }
- if (!(x & 0xC000000000000000ULL)) {
- x <<= 2;
- r -= 2;
- }
- if (!(x & 0x8000000000000000ULL)) {
- x <<= 1;
- r -= 1;
- }
- return r;
-}
-#endif
-
-#ifndef HAS_FLS_U32
-static __attribute__((unused))
-unsigned int fls_u32(uint32_t x)
-{
- unsigned int r = 32;
-
- if (!x)
- return 0;
- if (!(x & 0xFFFF0000U)) {
- x <<= 16;
- r -= 16;
- }
- if (!(x & 0xFF000000U)) {
- x <<= 8;
- r -= 8;
- }
- if (!(x & 0xF0000000U)) {
- x <<= 4;
- r -= 4;
- }
- if (!(x & 0xC0000000U)) {
- x <<= 2;
- r -= 2;
- }
- if (!(x & 0x80000000U)) {
- x <<= 1;
- r -= 1;
- }
- return r;
-}
-#endif
-
-unsigned int fls_ulong(unsigned long x)
-{
-#if (CAA_BITS_PER_LONG == 32)
- return fls_u32(x);
-#else
- return fls_u64(x);
-#endif
-}
-
-/*
- * Return the minimum order for which x <= (1UL << order).
- * Return -1 if x is 0.
- */
-int get_count_order_u32(uint32_t x)
-{
- if (!x)
- return -1;
-
- return fls_u32(x - 1);
-}
-
-/*
- * Return the minimum order for which x <= (1UL << order).
- * Return -1 if x is 0.
- */
-int get_count_order_ulong(unsigned long x)
-{
- if (!x)
- return -1;
-
- return fls_ulong(x - 1);
-}
-
-#ifdef POISON_FREE
-#define poison_free(ptr) \
- do { \
- if (ptr) { \
- memset(ptr, 0x42, sizeof(*(ptr))); \
- free(ptr); \
- } \
- } while (0)
-#else
-#define poison_free(ptr) free(ptr)
-#endif
-
-static
-void cds_lfht_resize_lazy(struct cds_lfht *ht, unsigned long size, int growth);
-
-static
-void cds_lfht_resize_lazy_count(struct cds_lfht *ht, unsigned long size,
- unsigned long count);
-
-static long nr_cpus_mask = -1;
-static long split_count_mask = -1;
-
-#if defined(HAVE_SYSCONF)
-static void ht_init_nr_cpus_mask(void)
-{
- long maxcpus;
-
- maxcpus = sysconf(_SC_NPROCESSORS_CONF);
- if (maxcpus <= 0) {
- nr_cpus_mask = -2;
- return;
- }
- /*
- * round up number of CPUs to next power of two, so we
- * can use & for modulo.
- */
- maxcpus = 1UL << get_count_order_ulong(maxcpus);
- nr_cpus_mask = maxcpus - 1;
-}
-#else /* #if defined(HAVE_SYSCONF) */
-static void ht_init_nr_cpus_mask(void)
-{
- nr_cpus_mask = -2;
-}
-#endif /* #else #if defined(HAVE_SYSCONF) */
-
-static
-void alloc_split_items_count(struct cds_lfht *ht)
-{
- struct ht_items_count *count;
-
- if (nr_cpus_mask == -1) {
- ht_init_nr_cpus_mask();
- if (nr_cpus_mask < 0)
- split_count_mask = DEFAULT_SPLIT_COUNT_MASK;
- else
- split_count_mask = nr_cpus_mask;
- }
-
- assert(split_count_mask >= 0);
-
- if (ht->flags & CDS_LFHT_ACCOUNTING) {
- ht->split_count = calloc(split_count_mask + 1, sizeof(*count));
- assert(ht->split_count);
- } else {
- ht->split_count = NULL;
- }
-}
-
-static
-void free_split_items_count(struct cds_lfht *ht)
-{
- poison_free(ht->split_count);
-}
-
-#if defined(HAVE_SCHED_GETCPU)
-static
-int ht_get_split_count_index(unsigned long hash)
-{
- int cpu;
-
- assert(split_count_mask >= 0);
- cpu = sched_getcpu();
- if (caa_unlikely(cpu < 0))
- return hash & split_count_mask;
- else
- return cpu & split_count_mask;
-}
-#else /* #if defined(HAVE_SCHED_GETCPU) */
-static
-int ht_get_split_count_index(unsigned long hash)
-{
- return hash & split_count_mask;
-}
-#endif /* #else #if defined(HAVE_SCHED_GETCPU) */
-
-static
-void ht_count_add(struct cds_lfht *ht, unsigned long size, unsigned long hash)
-{
- unsigned long split_count;
- int index;
-
- if (caa_unlikely(!ht->split_count))
- return;
- index = ht_get_split_count_index(hash);
- split_count = uatomic_add_return(&ht->split_count[index].add, 1);
- if (caa_unlikely(!(split_count & ((1UL << COUNT_COMMIT_ORDER) - 1)))) {
- long count;
-
- dbg_printf("add split count %lu\n", split_count);
- count = uatomic_add_return(&ht->count,
- 1UL << COUNT_COMMIT_ORDER);
- /* If power of 2 */
- if (!(count & (count - 1))) {
- if ((count >> CHAIN_LEN_RESIZE_THRESHOLD) < size)
- return;
- dbg_printf("add set global %ld\n", count);
- cds_lfht_resize_lazy_count(ht, size,
- count >> (CHAIN_LEN_TARGET - 1));
- }
- }
-}
-
-static
-void ht_count_del(struct cds_lfht *ht, unsigned long size, unsigned long hash)
-{
- unsigned long split_count;
- int index;
-
- if (caa_unlikely(!ht->split_count))
- return;
- index = ht_get_split_count_index(hash);
- split_count = uatomic_add_return(&ht->split_count[index].del, 1);
- if (caa_unlikely(!(split_count & ((1UL << COUNT_COMMIT_ORDER) - 1)))) {
- long count;
-
- dbg_printf("del split count %lu\n", split_count);
- count = uatomic_add_return(&ht->count,
- -(1UL << COUNT_COMMIT_ORDER));
- /* If power of 2 */
- if (!(count & (count - 1))) {
- if ((count >> CHAIN_LEN_RESIZE_THRESHOLD) >= size)
- return;
- dbg_printf("del set global %ld\n", count);
- /*
- * Don't shrink table if the number of nodes is below a
- * certain threshold.
- */
- if (count < (1UL << COUNT_COMMIT_ORDER) * (split_count_mask + 1))
- return;
- cds_lfht_resize_lazy_count(ht, size,
- count >> (CHAIN_LEN_TARGET - 1));
- }
- }
-}
-
-static
-void check_resize(struct cds_lfht *ht, unsigned long size, uint32_t chain_len)
-{
- unsigned long count;
-
- if (!(ht->flags & CDS_LFHT_AUTO_RESIZE))
- return;
- count = uatomic_read(&ht->count);
- /*
- * Use bucket-local length for small table expand and for
- * environments lacking per-cpu data support.
- */
- if (count >= (1UL << COUNT_COMMIT_ORDER))
- return;
- if (chain_len > 100)
- dbg_printf("WARNING: large chain length: %u.\n",
- chain_len);
- if (chain_len >= CHAIN_LEN_RESIZE_THRESHOLD)
- cds_lfht_resize_lazy(ht, size,
- get_count_order_u32(chain_len - (CHAIN_LEN_TARGET - 1)));
-}
-
-static
-struct cds_lfht_node *clear_flag(struct cds_lfht_node *node)
-{
- return (struct cds_lfht_node *) (((unsigned long) node) & ~FLAGS_MASK);
-}
-
-static
-int is_removed(struct cds_lfht_node *node)
-{
- return ((unsigned long) node) & REMOVED_FLAG;
-}
-
-static
-struct cds_lfht_node *flag_removed(struct cds_lfht_node *node)
-{
- return (struct cds_lfht_node *) (((unsigned long) node) | REMOVED_FLAG);
-}
-
-static
-int is_dummy(struct cds_lfht_node *node)
-{
- return ((unsigned long) node) & DUMMY_FLAG;
-}
-
-static
-struct cds_lfht_node *flag_dummy(struct cds_lfht_node *node)
-{
- return (struct cds_lfht_node *) (((unsigned long) node) | DUMMY_FLAG);
-}
-
-static
-struct cds_lfht_node *get_end(void)
-{
- return (struct cds_lfht_node *) END_VALUE;
-}
-
-static
-int is_end(struct cds_lfht_node *node)
-{
- return clear_flag(node) == (struct cds_lfht_node *) END_VALUE;
-}
-
-static
-unsigned long _uatomic_max(unsigned long *ptr, unsigned long v)
-{
- unsigned long old1, old2;
-
- old1 = uatomic_read(ptr);
- do {
- old2 = old1;
- if (old2 >= v)
- return old2;
- } while ((old1 = uatomic_cmpxchg(ptr, old2, v)) != old2);
- return v;
-}
-
-static
-struct _cds_lfht_node *lookup_bucket(struct cds_lfht *ht, unsigned long size,
- unsigned long hash)
-{
- unsigned long index, order;
-
- assert(size > 0);
- index = hash & (size - 1);
-
- if (index < ht->min_alloc_size) {
- dbg_printf("lookup hash %lu index %lu order 0 aridx 0\n",
- hash, index);
- return &ht->t.tbl[0]->nodes[index];
- }
- /*
- * equivalent to get_count_order_ulong(index + 1), but optimizes
- * away the non-existing 0 special-case for
- * get_count_order_ulong.
- */
- order = fls_ulong(index);
- dbg_printf("lookup hash %lu index %lu order %lu aridx %lu\n",
- hash, index, order, index & ((1UL << (order - 1)) - 1));
- return &ht->t.tbl[order]->nodes[index & ((1UL << (order - 1)) - 1)];
-}
-
-/*
- * Remove all logically deleted nodes from a bucket up to a certain node key.
- */
-static
-void _cds_lfht_gc_bucket(struct cds_lfht_node *dummy, struct cds_lfht_node *node)
-{
- struct cds_lfht_node *iter_prev, *iter, *next, *new_next;
-
- assert(!is_dummy(dummy));
- assert(!is_removed(dummy));
- assert(!is_dummy(node));
- assert(!is_removed(node));
- for (;;) {
- iter_prev = dummy;
- /* We can always skip the dummy node initially */
- iter = rcu_dereference(iter_prev->p.next);
- assert(!is_removed(iter));
- assert(iter_prev->p.reverse_hash <= node->p.reverse_hash);
- /*
- * We should never be called with dummy (start of chain)
- * and logically removed node (end of path compression
- * marker) being the actual same node. This would be a
- * bug in the algorithm implementation.
- */
- assert(dummy != node);
- for (;;) {
- if (caa_unlikely(is_end(iter)))
- return;
- if (caa_likely(clear_flag(iter)->p.reverse_hash > node->p.reverse_hash))
- return;
- next = rcu_dereference(clear_flag(iter)->p.next);
- if (caa_likely(is_removed(next)))
- break;
- iter_prev = clear_flag(iter);
- iter = next;
- }
- assert(!is_removed(iter));
- if (is_dummy(iter))
- new_next = flag_dummy(clear_flag(next));
- else
- new_next = clear_flag(next);
- (void) uatomic_cmpxchg(&iter_prev->p.next, iter, new_next);
- }
- return;
-}
-
-static
-int _cds_lfht_replace(struct cds_lfht *ht, unsigned long size,
- struct cds_lfht_node *old_node,
- struct cds_lfht_node *old_next,
- struct cds_lfht_node *new_node)
-{
- struct cds_lfht_node *dummy, *ret_next;
- struct _cds_lfht_node *lookup;
-
- if (!old_node) /* Return -ENOENT if asked to replace NULL node */
- return -ENOENT;
-
- assert(!is_removed(old_node));
- assert(!is_dummy(old_node));
- assert(!is_removed(new_node));
- assert(!is_dummy(new_node));
- assert(new_node != old_node);
- for (;;) {
- /* Insert after node to be replaced */
- if (is_removed(old_next)) {
- /*
- * Too late, the old node has been removed under us
- * between lookup and replace. Fail.
- */
- return -ENOENT;
- }
- assert(!is_dummy(old_next));
- assert(new_node != clear_flag(old_next));
- new_node->p.next = clear_flag(old_next);
- /*
- * Here is the whole trick for lock-free replace: we add
- * the replacement node _after_ the node we want to
- * replace by atomically setting its next pointer at the
- * same time we set its removal flag. Given that
- * the lookups/get next use an iterator aware of the
- * next pointer, they will either skip the old node due
- * to the removal flag and see the new node, or use
- * the old node, but will not see the new one.
- */
- ret_next = uatomic_cmpxchg(&old_node->p.next,
- old_next, flag_removed(new_node));
- if (ret_next == old_next)
- break; /* We performed the replacement. */
- old_next = ret_next;
- }
-
- /*
- * Ensure that the old node is not visible to readers anymore:
- * lookup for the node, and remove it (along with any other
- * logically removed node) if found.
- */
- lookup = lookup_bucket(ht, size, bit_reverse_ulong(old_node->p.reverse_hash));
- dummy = (struct cds_lfht_node *) lookup;
- _cds_lfht_gc_bucket(dummy, new_node);
-
- assert(is_removed(rcu_dereference(old_node->p.next)));
- return 0;
-}
-
-/*
- * A non-NULL unique_ret pointer uses the "add unique" (or uniquify) add
- * mode. A NULL unique_ret allows creation of duplicate keys.
- */
-static
-void _cds_lfht_add(struct cds_lfht *ht,
- unsigned long size,
- struct cds_lfht_node *node,
- struct cds_lfht_iter *unique_ret,
- int dummy)
-{
- struct cds_lfht_node *iter_prev, *iter, *next, *new_node, *new_next,
- *return_node;
- struct _cds_lfht_node *lookup;
-
- assert(!is_dummy(node));
- assert(!is_removed(node));
- lookup = lookup_bucket(ht, size, bit_reverse_ulong(node->p.reverse_hash));
- for (;;) {
- uint32_t chain_len = 0;
-
- /*
- * iter_prev points to the non-removed node prior to the
- * insert location.
- */
- iter_prev = (struct cds_lfht_node *) lookup;
- /* We can always skip the dummy node initially */
- iter = rcu_dereference(iter_prev->p.next);
- assert(iter_prev->p.reverse_hash <= node->p.reverse_hash);
- for (;;) {
- if (caa_unlikely(is_end(iter)))
- goto insert;
- if (caa_likely(clear_flag(iter)->p.reverse_hash > node->p.reverse_hash))
- goto insert;
-
- /* dummy node is the first node of the identical-hash-value chain */
- if (dummy && clear_flag(iter)->p.reverse_hash == node->p.reverse_hash)
- goto insert;
-
- next = rcu_dereference(clear_flag(iter)->p.next);
- if (caa_unlikely(is_removed(next)))
- goto gc_node;
-
- /* uniquely add */
- if (unique_ret
- && !is_dummy(next)
- && clear_flag(iter)->p.reverse_hash == node->p.reverse_hash) {
- struct cds_lfht_iter d_iter = { .node = node, .next = iter, };
-
- /*
- * uniquely adding inserts the node as the first
- * node of the identical-hash-value node chain.
- *
- * This semantic ensures no duplicated keys
- * should ever be observable in the table
- * (including observe one node by one node
- * by forward iterations)
- */
- cds_lfht_next_duplicate(ht, &d_iter);
- if (!d_iter.node)
- goto insert;
-
- *unique_ret = d_iter;
- return;
- }
-
- /* Only account for identical reverse hash once */
- if (iter_prev->p.reverse_hash != clear_flag(iter)->p.reverse_hash
- && !is_dummy(next))
- check_resize(ht, size, ++chain_len);
- iter_prev = clear_flag(iter);
- iter = next;
- }
-
- insert:
- assert(node != clear_flag(iter));
- assert(!is_removed(iter_prev));
- assert(!is_removed(iter));
- assert(iter_prev != node);
- if (!dummy)
- node->p.next = clear_flag(iter);
- else
- node->p.next = flag_dummy(clear_flag(iter));
- if (is_dummy(iter))
- new_node = flag_dummy(node);
- else
- new_node = node;
- if (uatomic_cmpxchg(&iter_prev->p.next, iter,
- new_node) != iter) {
- continue; /* retry */
- } else {
- return_node = node;
- goto end;
- }
-
- gc_node:
- assert(!is_removed(iter));
- if (is_dummy(iter))
- new_next = flag_dummy(clear_flag(next));
- else
- new_next = clear_flag(next);
- (void) uatomic_cmpxchg(&iter_prev->p.next, iter, new_next);
- /* retry */
- }
-end:
- if (unique_ret) {
- unique_ret->node = return_node;
- /* unique_ret->next left unset, never used. */
- }
-}
-
-static
-int _cds_lfht_del(struct cds_lfht *ht, unsigned long size,
- struct cds_lfht_node *node,
- int dummy_removal)
-{
- struct cds_lfht_node *dummy, *next, *old;
- struct _cds_lfht_node *lookup;
-
- if (!node) /* Return -ENOENT if asked to delete NULL node */
- return -ENOENT;
-
- /* logically delete the node */
- assert(!is_dummy(node));
- assert(!is_removed(node));
- old = rcu_dereference(node->p.next);
- do {
- struct cds_lfht_node *new_next;
-
- next = old;
- if (caa_unlikely(is_removed(next)))
- return -ENOENT;
- if (dummy_removal)
- assert(is_dummy(next));
- else
- assert(!is_dummy(next));
- new_next = flag_removed(next);
- old = uatomic_cmpxchg(&node->p.next, next, new_next);
- } while (old != next);
- /* We performed the (logical) deletion. */
-
- /*
- * Ensure that the node is not visible to readers anymore: lookup for
- * the node, and remove it (along with any other logically removed node)
- * if found.
- */
- lookup = lookup_bucket(ht, size, bit_reverse_ulong(node->p.reverse_hash));
- dummy = (struct cds_lfht_node *) lookup;
- _cds_lfht_gc_bucket(dummy, node);
-
- assert(is_removed(rcu_dereference(node->p.next)));
- return 0;
-}
-
-static
-void *partition_resize_thread(void *arg)
-{
- struct partition_resize_work *work = arg;
-
- work->ht->cds_lfht_rcu_register_thread();
- work->fct(work->ht, work->i, work->start, work->len);
- work->ht->cds_lfht_rcu_unregister_thread();
- return NULL;
-}
-
-static
-void partition_resize_helper(struct cds_lfht *ht, unsigned long i,
- unsigned long len,
- void (*fct)(struct cds_lfht *ht, unsigned long i,
- unsigned long start, unsigned long len))
-{
- unsigned long partition_len;
- struct partition_resize_work *work;
- int thread, ret;
- unsigned long nr_threads;
-
- /*
- * Note: nr_cpus_mask + 1 is always power of 2.
- * We spawn just the number of threads we need to satisfy the minimum
- * partition size, up to the number of CPUs in the system.
- */
- if (nr_cpus_mask > 0) {
- nr_threads = min(nr_cpus_mask + 1,
- len >> MIN_PARTITION_PER_THREAD_ORDER);
- } else {
- nr_threads = 1;
- }
- partition_len = len >> get_count_order_ulong(nr_threads);
- work = calloc(nr_threads, sizeof(*work));
- assert(work);
- for (thread = 0; thread < nr_threads; thread++) {
- work[thread].ht = ht;
- work[thread].i = i;
- work[thread].len = partition_len;
- work[thread].start = thread * partition_len;
- work[thread].fct = fct;
- ret = pthread_create(&(work[thread].thread_id), ht->resize_attr,
- partition_resize_thread, &work[thread]);
- assert(!ret);
- }
- for (thread = 0; thread < nr_threads; thread++) {
- ret = pthread_join(work[thread].thread_id, NULL);
- assert(!ret);
- }
- free(work);
-}
-
-/*
- * Holding RCU read lock to protect _cds_lfht_add against memory
- * reclaim that could be performed by other call_rcu worker threads (ABA
- * problem).
- *
- * When we reach a certain length, we can split this population phase over
- * many worker threads, based on the number of CPUs available in the system.
- * This should therefore take care of not having the expand lagging behind too
- * many concurrent insertion threads by using the scheduler's ability to
- * schedule dummy node population fairly with insertions.
- */
-static
-void init_table_populate_partition(struct cds_lfht *ht, unsigned long i,
- unsigned long start, unsigned long len)
-{
- unsigned long j;
-
- assert(i > ht->min_alloc_order);
- ht->cds_lfht_rcu_read_lock();
- for (j = start; j < start + len; j++) {
- struct cds_lfht_node *new_node =
- (struct cds_lfht_node *) &ht->t.tbl[i]->nodes[j];
-
- dbg_printf("init populate: i %lu j %lu hash %lu\n",
- i, j, (1UL << (i - 1)) + j);
- new_node->p.reverse_hash =
- bit_reverse_ulong((1UL << (i - 1)) + j);
- _cds_lfht_add(ht, 1UL << (i - 1),
- new_node, NULL, 1);
- }
- ht->cds_lfht_rcu_read_unlock();
-}
-
-static
-void init_table_populate(struct cds_lfht *ht, unsigned long i,
- unsigned long len)
-{
- assert(nr_cpus_mask != -1);
- if (nr_cpus_mask < 0 || len < 2 * MIN_PARTITION_PER_THREAD) {
- ht->cds_lfht_rcu_thread_online();
- init_table_populate_partition(ht, i, 0, len);
- ht->cds_lfht_rcu_thread_offline();
- return;
- }
- partition_resize_helper(ht, i, len, init_table_populate_partition);
-}
-
-static
-void init_table(struct cds_lfht *ht,
- unsigned long first_order, unsigned long last_order)
-{
- unsigned long i;
-
- dbg_printf("init table: first_order %lu last_order %lu\n",
- first_order, last_order);
- assert(first_order > ht->min_alloc_order);
- for (i = first_order; i <= last_order; i++) {
- unsigned long len;
-
- len = 1UL << (i - 1);
- dbg_printf("init order %lu len: %lu\n", i, len);
-
- /* Stop expand if the resize target changes under us */
- if (CMM_LOAD_SHARED(ht->t.resize_target) < (1UL << i))
- break;
-
- ht->t.tbl[i] = calloc(1, len * sizeof(struct _cds_lfht_node));
- assert(ht->t.tbl[i]);
-
- /*
- * Set all dummy nodes reverse hash values for a level and
- * link all dummy nodes into the table.
- */
- init_table_populate(ht, i, len);
-
- /*
- * Update table size.
- */
- cmm_smp_wmb(); /* populate data before RCU size */
- CMM_STORE_SHARED(ht->t.size, 1UL << i);
-
- dbg_printf("init new size: %lu\n", 1UL << i);
- if (CMM_LOAD_SHARED(ht->in_progress_destroy))
- break;
- }
-}
-
-/*
- * Holding RCU read lock to protect _cds_lfht_remove against memory
- * reclaim that could be performed by other call_rcu worker threads (ABA
- * problem).
- * For a single level, we logically remove and garbage collect each node.
- *
- * As a design choice, we perform logical removal and garbage collection on a
- * node-per-node basis to simplify this algorithm. We also assume keeping good
- * cache locality of the operation would overweight possible performance gain
- * that could be achieved by batching garbage collection for multiple levels.
- * However, this would have to be justified by benchmarks.
- *
- * Concurrent removal and add operations are helping us perform garbage
- * collection of logically removed nodes. We guarantee that all logically
- * removed nodes have been garbage-collected (unlinked) before call_rcu is
- * invoked to free a hole level of dummy nodes (after a grace period).
- *
- * Logical removal and garbage collection can therefore be done in batch or on a
- * node-per-node basis, as long as the guarantee above holds.
- *
- * When we reach a certain length, we can split this removal over many worker
- * threads, based on the number of CPUs available in the system. This should
- * take care of not letting resize process lag behind too many concurrent
- * updater threads actively inserting into the hash table.
- */
-static
-void remove_table_partition(struct cds_lfht *ht, unsigned long i,
- unsigned long start, unsigned long len)
-{
- unsigned long j;
-
- assert(i > ht->min_alloc_order);
- ht->cds_lfht_rcu_read_lock();
- for (j = start; j < start + len; j++) {
- struct cds_lfht_node *fini_node =
- (struct cds_lfht_node *) &ht->t.tbl[i]->nodes[j];
-
- dbg_printf("remove entry: i %lu j %lu hash %lu\n",
- i, j, (1UL << (i - 1)) + j);
- fini_node->p.reverse_hash =
- bit_reverse_ulong((1UL << (i - 1)) + j);
- (void) _cds_lfht_del(ht, 1UL << (i - 1), fini_node, 1);
- }
- ht->cds_lfht_rcu_read_unlock();
-}
-
-static
-void remove_table(struct cds_lfht *ht, unsigned long i, unsigned long len)
-{
-
- assert(nr_cpus_mask != -1);
- if (nr_cpus_mask < 0 || len < 2 * MIN_PARTITION_PER_THREAD) {
- ht->cds_lfht_rcu_thread_online();
- remove_table_partition(ht, i, 0, len);
- ht->cds_lfht_rcu_thread_offline();
- return;
- }
- partition_resize_helper(ht, i, len, remove_table_partition);
-}
-
-static
-void fini_table(struct cds_lfht *ht,
- unsigned long first_order, unsigned long last_order)
-{
- long i;
- void *free_by_rcu = NULL;
-
- dbg_printf("fini table: first_order %lu last_order %lu\n",
- first_order, last_order);
- assert(first_order > ht->min_alloc_order);
- for (i = last_order; i >= first_order; i--) {
- unsigned long len;
-
- len = 1UL << (i - 1);
- dbg_printf("fini order %lu len: %lu\n", i, len);
-
- /* Stop shrink if the resize target changes under us */
- if (CMM_LOAD_SHARED(ht->t.resize_target) > (1UL << (i - 1)))
- break;
-
- cmm_smp_wmb(); /* populate data before RCU size */
- CMM_STORE_SHARED(ht->t.size, 1UL << (i - 1));
-
- /*
- * We need to wait for all add operations to reach Q.S. (and
- * thus use the new table for lookups) before we can start
- * releasing the old dummy nodes. Otherwise their lookup will
- * return a logically removed node as insert position.
- */
- ht->cds_lfht_synchronize_rcu();
- if (free_by_rcu)
- free(free_by_rcu);
-
- /*
- * Set "removed" flag in dummy nodes about to be removed.
- * Unlink all now-logically-removed dummy node pointers.
- * Concurrent add/remove operation are helping us doing
- * the gc.
- */
- remove_table(ht, i, len);
-
- free_by_rcu = ht->t.tbl[i];
-
- dbg_printf("fini new size: %lu\n", 1UL << i);
- if (CMM_LOAD_SHARED(ht->in_progress_destroy))
- break;
- }
-
- if (free_by_rcu) {
- ht->cds_lfht_synchronize_rcu();
- free(free_by_rcu);
- }
-}
-
-static
-void cds_lfht_create_dummy(struct cds_lfht *ht, unsigned long size)
-{
- struct _cds_lfht_node *prev, *node;
- unsigned long order, len, i, j;
-
- ht->t.tbl[0] = calloc(1, ht->min_alloc_size * sizeof(struct _cds_lfht_node));
- assert(ht->t.tbl[0]);
-
- dbg_printf("create dummy: order %lu index %lu hash %lu\n", 0, 0, 0);
- ht->t.tbl[0]->nodes[0].next = flag_dummy(get_end());
- ht->t.tbl[0]->nodes[0].reverse_hash = 0;
-
- for (order = 1; order < get_count_order_ulong(size) + 1; order++) {
- len = 1UL << (order - 1);
- if (order <= ht->min_alloc_order) {
- ht->t.tbl[order] = (struct rcu_level *) (ht->t.tbl[0]->nodes + len);
- } else {
- ht->t.tbl[order] = calloc(1, len * sizeof(struct _cds_lfht_node));
- assert(ht->t.tbl[order]);
- }
-
- i = 0;
- prev = ht->t.tbl[i]->nodes;
- for (j = 0; j < len; j++) {
- if (j & (j - 1)) { /* Between power of 2 */
- prev++;
- } else if (j) { /* At each power of 2 */
- i++;
- prev = ht->t.tbl[i]->nodes;
- }
-
- node = &ht->t.tbl[order]->nodes[j];
- dbg_printf("create dummy: order %lu index %lu hash %lu\n",
- order, j, j + len);
- node->next = prev->next;
- assert(is_dummy(node->next));
- node->reverse_hash = bit_reverse_ulong(j + len);
- prev->next = flag_dummy((struct cds_lfht_node *)node);
- }
- }
-}
-
-struct cds_lfht *_cds_lfht_new(cds_lfht_hash_fct hash_fct,
- cds_lfht_compare_fct compare_fct,
- unsigned long hash_seed,
- unsigned long init_size,
- unsigned long min_alloc_size,
- int flags,
- void (*cds_lfht_call_rcu)(struct rcu_head *head,
- void (*func)(struct rcu_head *head)),
- void (*cds_lfht_synchronize_rcu)(void),
- void (*cds_lfht_rcu_read_lock)(void),
- void (*cds_lfht_rcu_read_unlock)(void),
- void (*cds_lfht_rcu_thread_offline)(void),
- void (*cds_lfht_rcu_thread_online)(void),
- void (*cds_lfht_rcu_register_thread)(void),
- void (*cds_lfht_rcu_unregister_thread)(void),
- pthread_attr_t *attr)
-{
- struct cds_lfht *ht;
- unsigned long order;
-
- /* min_alloc_size must be power of two */
- if (!min_alloc_size || (min_alloc_size & (min_alloc_size - 1)))
- return NULL;
- /* init_size must be power of two */
- if (!init_size || (init_size & (init_size - 1)))
- return NULL;
- min_alloc_size = max(min_alloc_size, MIN_TABLE_SIZE);
- init_size = max(init_size, min_alloc_size);
- ht = calloc(1, sizeof(struct cds_lfht));
- assert(ht);
- ht->flags = flags;
- ht->hash_fct = hash_fct;
- ht->compare_fct = compare_fct;
- ht->hash_seed = hash_seed;
- ht->cds_lfht_call_rcu = cds_lfht_call_rcu;
- ht->cds_lfht_synchronize_rcu = cds_lfht_synchronize_rcu;
- ht->cds_lfht_rcu_read_lock = cds_lfht_rcu_read_lock;
- ht->cds_lfht_rcu_read_unlock = cds_lfht_rcu_read_unlock;
- ht->cds_lfht_rcu_thread_offline = cds_lfht_rcu_thread_offline;
- ht->cds_lfht_rcu_thread_online = cds_lfht_rcu_thread_online;
- ht->cds_lfht_rcu_register_thread = cds_lfht_rcu_register_thread;
- ht->cds_lfht_rcu_unregister_thread = cds_lfht_rcu_unregister_thread;
- ht->resize_attr = attr;
- alloc_split_items_count(ht);
- /* this mutex should not nest in read-side C.S. */
- pthread_mutex_init(&ht->resize_mutex, NULL);
- order = get_count_order_ulong(init_size);
- ht->t.resize_target = 1UL << order;
- ht->min_alloc_size = min_alloc_size;
- ht->min_alloc_order = get_count_order_ulong(min_alloc_size);
- cds_lfht_create_dummy(ht, 1UL << order);
- ht->t.size = 1UL << order;
- return ht;
-}
-
-void cds_lfht_lookup(struct cds_lfht *ht, void *key, size_t key_len,
- struct cds_lfht_iter *iter)
-{
- struct cds_lfht_node *node, *next, *dummy_node;
- struct _cds_lfht_node *lookup;
- unsigned long hash, reverse_hash, size;
-
- hash = ht->hash_fct(key, key_len, ht->hash_seed);
- reverse_hash = bit_reverse_ulong(hash);
-
- size = rcu_dereference(ht->t.size);
- lookup = lookup_bucket(ht, size, hash);
- dummy_node = (struct cds_lfht_node *) lookup;
- /* We can always skip the dummy node initially */
- node = rcu_dereference(dummy_node->p.next);
- node = clear_flag(node);
- for (;;) {
- if (caa_unlikely(is_end(node))) {
- node = next = NULL;
- break;
- }
- if (caa_unlikely(node->p.reverse_hash > reverse_hash)) {
- node = next = NULL;
- break;
- }
- next = rcu_dereference(node->p.next);
- assert(node == clear_flag(node));
- if (caa_likely(!is_removed(next))
- && !is_dummy(next)
- && node->p.reverse_hash == reverse_hash
- && caa_likely(!ht->compare_fct(node->key, node->key_len, key, key_len))) {
- break;
- }
- node = clear_flag(next);
- }
- assert(!node || !is_dummy(rcu_dereference(node->p.next)));
- iter->node = node;
- iter->next = next;
-}
-
-void cds_lfht_next_duplicate(struct cds_lfht *ht, struct cds_lfht_iter *iter)
-{
- struct cds_lfht_node *node, *next;
- unsigned long reverse_hash;
- void *key;
- size_t key_len;
-
- node = iter->node;
- reverse_hash = node->p.reverse_hash;
- key = node->key;
- key_len = node->key_len;
- next = iter->next;
- node = clear_flag(next);
-
- for (;;) {
- if (caa_unlikely(is_end(node))) {
- node = next = NULL;
- break;
- }
- if (caa_unlikely(node->p.reverse_hash > reverse_hash)) {
- node = next = NULL;
- break;
- }
- next = rcu_dereference(node->p.next);
- if (caa_likely(!is_removed(next))
- && !is_dummy(next)
- && caa_likely(!ht->compare_fct(node->key, node->key_len, key, key_len))) {
- break;
- }
- node = clear_flag(next);
- }
- assert(!node || !is_dummy(rcu_dereference(node->p.next)));
- iter->node = node;
- iter->next = next;
-}
-
-void cds_lfht_next(struct cds_lfht *ht, struct cds_lfht_iter *iter)
-{
- struct cds_lfht_node *node, *next;
-
- node = clear_flag(iter->next);
- for (;;) {
- if (caa_unlikely(is_end(node))) {
- node = next = NULL;
- break;
- }
- next = rcu_dereference(node->p.next);
- if (caa_likely(!is_removed(next))
- && !is_dummy(next)) {
- break;
- }
- node = clear_flag(next);
- }
- assert(!node || !is_dummy(rcu_dereference(node->p.next)));
- iter->node = node;
- iter->next = next;
-}
-
-void cds_lfht_first(struct cds_lfht *ht, struct cds_lfht_iter *iter)
-{
- struct _cds_lfht_node *lookup;
-
- /*
- * Get next after first dummy node. The first dummy node is the
- * first node of the linked list.
- */
- lookup = &ht->t.tbl[0]->nodes[0];
- iter->next = lookup->next;
- cds_lfht_next(ht, iter);
-}
-
-void cds_lfht_add(struct cds_lfht *ht, struct cds_lfht_node *node)
-{
- unsigned long hash, size;
-
- hash = ht->hash_fct(node->key, node->key_len, ht->hash_seed);
- node->p.reverse_hash = bit_reverse_ulong((unsigned long) hash);
-
- size = rcu_dereference(ht->t.size);
- _cds_lfht_add(ht, size, node, NULL, 0);
- ht_count_add(ht, size, hash);
-}
-
-struct cds_lfht_node *cds_lfht_add_unique(struct cds_lfht *ht,
- struct cds_lfht_node *node)
-{
- unsigned long hash, size;
- struct cds_lfht_iter iter;
-
- hash = ht->hash_fct(node->key, node->key_len, ht->hash_seed);
- node->p.reverse_hash = bit_reverse_ulong((unsigned long) hash);
-
- size = rcu_dereference(ht->t.size);
- _cds_lfht_add(ht, size, node, &iter, 0);
- if (iter.node == node)
- ht_count_add(ht, size, hash);
- return iter.node;
-}
-
-struct cds_lfht_node *cds_lfht_add_replace(struct cds_lfht *ht,
- struct cds_lfht_node *node)
-{
- unsigned long hash, size;
- struct cds_lfht_iter iter;
-
- hash = ht->hash_fct(node->key, node->key_len, ht->hash_seed);
- node->p.reverse_hash = bit_reverse_ulong((unsigned long) hash);
-
- size = rcu_dereference(ht->t.size);
- for (;;) {
- _cds_lfht_add(ht, size, node, &iter, 0);
- if (iter.node == node) {
- ht_count_add(ht, size, hash);
- return NULL;
- }
-
- if (!_cds_lfht_replace(ht, size, iter.node, iter.next, node))
- return iter.node;
- }
-}
-
-int cds_lfht_replace(struct cds_lfht *ht, struct cds_lfht_iter *old_iter,
- struct cds_lfht_node *new_node)
-{
- unsigned long size;
-
- size = rcu_dereference(ht->t.size);
- return _cds_lfht_replace(ht, size, old_iter->node, old_iter->next,
- new_node);
-}
-
-int cds_lfht_del(struct cds_lfht *ht, struct cds_lfht_iter *iter)
-{
- unsigned long size, hash;
- int ret;
-
- size = rcu_dereference(ht->t.size);
- ret = _cds_lfht_del(ht, size, iter->node, 0);
- if (!ret) {
- hash = bit_reverse_ulong(iter->node->p.reverse_hash);
- ht_count_del(ht, size, hash);
- }
- return ret;
-}
-
-static
-int cds_lfht_delete_dummy(struct cds_lfht *ht)
-{
- struct cds_lfht_node *node;
- struct _cds_lfht_node *lookup;
- unsigned long order, i, size;
-
- /* Check that the table is empty */
- lookup = &ht->t.tbl[0]->nodes[0];
- node = (struct cds_lfht_node *) lookup;
- do {
- node = clear_flag(node)->p.next;
- if (!is_dummy(node))
- return -EPERM;
- assert(!is_removed(node));
- } while (!is_end(node));
- /*
- * size accessed without rcu_dereference because hash table is
- * being destroyed.
- */
- size = ht->t.size;
- /* Internal sanity check: all nodes left should be dummy */
- for (order = 0; order < get_count_order_ulong(size) + 1; order++) {
- unsigned long len;
-
- len = !order ? 1 : 1UL << (order - 1);
- for (i = 0; i < len; i++) {
- dbg_printf("delete order %lu i %lu hash %lu\n",
- order, i,
- bit_reverse_ulong(ht->t.tbl[order]->nodes[i].reverse_hash));
- assert(is_dummy(ht->t.tbl[order]->nodes[i].next));
- }
-
- if (order == ht->min_alloc_order)
- poison_free(ht->t.tbl[0]);
- else if (order > ht->min_alloc_order)
- poison_free(ht->t.tbl[order]);
- /* Nothing to delete for order < ht->min_alloc_order */
- }
- return 0;
-}
-
-/*
- * Should only be called when no more concurrent readers nor writers can
- * possibly access the table.
- */
-int cds_lfht_destroy(struct cds_lfht *ht, pthread_attr_t **attr)
-{
- int ret;
-
- /* Wait for in-flight resize operations to complete */
- _CMM_STORE_SHARED(ht->in_progress_destroy, 1);
- cmm_smp_mb(); /* Store destroy before load resize */
- while (uatomic_read(&ht->in_progress_resize))
- poll(NULL, 0, 100); /* wait for 100ms */
- ret = cds_lfht_delete_dummy(ht);
- if (ret)
- return ret;
- free_split_items_count(ht);
- if (attr)
- *attr = ht->resize_attr;
- poison_free(ht);
- return ret;
-}
-
-void cds_lfht_count_nodes(struct cds_lfht *ht,
- long *approx_before,
- unsigned long *count,
- unsigned long *removed,
- long *approx_after)
-{
- struct cds_lfht_node *node, *next;
- struct _cds_lfht_node *lookup;
- unsigned long nr_dummy = 0;
-
- *approx_before = 0;
- if (ht->split_count) {
- int i;
-
- for (i = 0; i < split_count_mask + 1; i++) {
- *approx_before += uatomic_read(&ht->split_count[i].add);
- *approx_before -= uatomic_read(&ht->split_count[i].del);
- }
- }
-
- *count = 0;
- *removed = 0;
-
- /* Count non-dummy nodes in the table */
- lookup = &ht->t.tbl[0]->nodes[0];
- node = (struct cds_lfht_node *) lookup;
- do {
- next = rcu_dereference(node->p.next);
- if (is_removed(next)) {
- if (!is_dummy(next))
- (*removed)++;
- else
- (nr_dummy)++;
- } else if (!is_dummy(next))
- (*count)++;
- else
- (nr_dummy)++;
- node = clear_flag(next);
- } while (!is_end(node));
- dbg_printf("number of dummy nodes: %lu\n", nr_dummy);
- *approx_after = 0;
- if (ht->split_count) {
- int i;
-
- for (i = 0; i < split_count_mask + 1; i++) {
- *approx_after += uatomic_read(&ht->split_count[i].add);
- *approx_after -= uatomic_read(&ht->split_count[i].del);
- }
- }
-}
-
-/* called with resize mutex held */
-static
-void _do_cds_lfht_grow(struct cds_lfht *ht,
- unsigned long old_size, unsigned long new_size)
-{
- unsigned long old_order, new_order;
-
- old_order = get_count_order_ulong(old_size);
- new_order = get_count_order_ulong(new_size);
- dbg_printf("resize from %lu (order %lu) to %lu (order %lu) buckets\n",
- old_size, old_order, new_size, new_order);
- assert(new_size > old_size);
- init_table(ht, old_order + 1, new_order);
-}
-
-/* called with resize mutex held */
-static
-void _do_cds_lfht_shrink(struct cds_lfht *ht,
- unsigned long old_size, unsigned long new_size)
-{
- unsigned long old_order, new_order;
-
- new_size = max(new_size, ht->min_alloc_size);
- old_order = get_count_order_ulong(old_size);
- new_order = get_count_order_ulong(new_size);
- dbg_printf("resize from %lu (order %lu) to %lu (order %lu) buckets\n",
- old_size, old_order, new_size, new_order);
- assert(new_size < old_size);
-
- /* Remove and unlink all dummy nodes to remove. */
- fini_table(ht, new_order + 1, old_order);
-}
-
-
-/* called with resize mutex held */
-static
-void _do_cds_lfht_resize(struct cds_lfht *ht)
-{
- unsigned long new_size, old_size;
-
- /*
- * Resize table, re-do if the target size has changed under us.
- */
- do {
- assert(uatomic_read(&ht->in_progress_resize));
- if (CMM_LOAD_SHARED(ht->in_progress_destroy))
- break;
- ht->t.resize_initiated = 1;
- old_size = ht->t.size;
- new_size = CMM_LOAD_SHARED(ht->t.resize_target);
- if (old_size < new_size)
- _do_cds_lfht_grow(ht, old_size, new_size);
- else if (old_size > new_size)
- _do_cds_lfht_shrink(ht, old_size, new_size);
- ht->t.resize_initiated = 0;
- /* write resize_initiated before read resize_target */
- cmm_smp_mb();
- } while (ht->t.size != CMM_LOAD_SHARED(ht->t.resize_target));
-}
-
-static
-unsigned long resize_target_update(struct cds_lfht *ht, unsigned long size,
- int growth_order)
-{
- return _uatomic_max(&ht->t.resize_target,
- size << growth_order);
-}
-
-static
-void resize_target_update_count(struct cds_lfht *ht,
- unsigned long count)
-{
- count = max(count, ht->min_alloc_size);
- uatomic_set(&ht->t.resize_target, count);
-}
-
-void cds_lfht_resize(struct cds_lfht *ht, unsigned long new_size)
-{
- resize_target_update_count(ht, new_size);
- CMM_STORE_SHARED(ht->t.resize_initiated, 1);
- ht->cds_lfht_rcu_thread_offline();
- pthread_mutex_lock(&ht->resize_mutex);
- _do_cds_lfht_resize(ht);
- pthread_mutex_unlock(&ht->resize_mutex);
- ht->cds_lfht_rcu_thread_online();
-}
-
-static
-void do_resize_cb(struct rcu_head *head)
-{
- struct rcu_resize_work *work =
- caa_container_of(head, struct rcu_resize_work, head);
- struct cds_lfht *ht = work->ht;
-
- ht->cds_lfht_rcu_thread_offline();
- pthread_mutex_lock(&ht->resize_mutex);
- _do_cds_lfht_resize(ht);
- pthread_mutex_unlock(&ht->resize_mutex);
- ht->cds_lfht_rcu_thread_online();
- poison_free(work);
- cmm_smp_mb(); /* finish resize before decrement */
- uatomic_dec(&ht->in_progress_resize);
-}
-
-static
-void cds_lfht_resize_lazy(struct cds_lfht *ht, unsigned long size, int growth)
-{
- struct rcu_resize_work *work;
- unsigned long target_size;
-
- target_size = resize_target_update(ht, size, growth);
- /* Store resize_target before read resize_initiated */
- cmm_smp_mb();
- if (!CMM_LOAD_SHARED(ht->t.resize_initiated) && size < target_size) {
- uatomic_inc(&ht->in_progress_resize);
- cmm_smp_mb(); /* increment resize count before load destroy */
- if (CMM_LOAD_SHARED(ht->in_progress_destroy)) {
- uatomic_dec(&ht->in_progress_resize);
- return;
- }
- work = malloc(sizeof(*work));
- work->ht = ht;
- ht->cds_lfht_call_rcu(&work->head, do_resize_cb);
- CMM_STORE_SHARED(ht->t.resize_initiated, 1);
- }
-}
-
-static
-void cds_lfht_resize_lazy_count(struct cds_lfht *ht, unsigned long size,
- unsigned long count)
-{
- struct rcu_resize_work *work;
-
- if (!(ht->flags & CDS_LFHT_AUTO_RESIZE))
- return;
- resize_target_update_count(ht, count);
- /* Store resize_target before read resize_initiated */
- cmm_smp_mb();
- if (!CMM_LOAD_SHARED(ht->t.resize_initiated)) {
- uatomic_inc(&ht->in_progress_resize);
- cmm_smp_mb(); /* increment resize count before load destroy */
- if (CMM_LOAD_SHARED(ht->in_progress_destroy)) {
- uatomic_dec(&ht->in_progress_resize);
- return;
- }
- work = malloc(sizeof(*work));
- work->ht = ht;
- ht->cds_lfht_call_rcu(&work->head, do_resize_cb);
- CMM_STORE_SHARED(ht->t.resize_initiated, 1);
- }
-}
+++ /dev/null
-#ifndef _URCU_RCULFHASH_H
-#define _URCU_RCULFHASH_H
-
-/*
- * urcu/rculfhash.h
- *
- * Userspace RCU library - Lock-Free RCU Hash Table
- *
- * Copyright 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- *
- * Include this file _after_ including your URCU flavor.
- */
-
-#include <stdint.h>
-#include <urcu-call-rcu.h>
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/*
- * struct cds_lfht_node and struct _cds_lfht_node should be aligned on
- * 4-bytes boundaries because the two lower bits are used as flags.
- */
-
-/*
- * _cds_lfht_node: Contains the internal pointers and reverse-hash
- * value required for lookup and traversal of the hash table.
- */
-struct _cds_lfht_node {
- struct cds_lfht_node *next; /* ptr | DUMMY_FLAG | REMOVED_FLAG */
- unsigned long reverse_hash;
-} __attribute__((aligned(4)));
-
-/*
- * cds_lfht_node: Contains the full key and length required to check for
- * an actual match, and also contains an rcu_head structure that is used
- * by RCU to track a node through a given RCU grace period. There is an
- * instance of _cds_lfht_node enclosed as a field within each
- * _cds_lfht_node structure.
- *
- * struct cds_lfht_node can be embedded into a structure (as a field).
- * caa_container_of() can be used to get the structure from the struct
- * cds_lfht_node after a lookup.
- */
-struct cds_lfht_node {
- /* cache-hot for iteration */
- struct _cds_lfht_node p; /* needs to be first field */
- void *key;
- unsigned int key_len;
- /* cache-cold for iteration */
- struct rcu_head head;
-};
-
-/* cds_lfht_iter: Used to track state while traversing a hash chain. */
-struct cds_lfht_iter {
- struct cds_lfht_node *node, *next;
-};
-
-static inline
-struct cds_lfht_node *cds_lfht_iter_get_node(struct cds_lfht_iter *iter)
-{
- return iter->node;
-}
-
-struct cds_lfht;
-
-/*
- * Caution !
- * Ensure reader and writer threads are registered as urcu readers.
- */
-
-typedef unsigned long (*cds_lfht_hash_fct)(void *key, size_t length,
- unsigned long seed);
-typedef unsigned long (*cds_lfht_compare_fct)(void *key1, size_t key1_len,
- void *key2, size_t key2_len);
-
-/*
- * cds_lfht_node_init - initialize a hash table node
- */
-static inline
-void cds_lfht_node_init(struct cds_lfht_node *node, void *key,
- size_t key_len)
-{
- node->key = key;
- node->key_len = key_len;
-}
-
-/*
- * Hash table creation flags.
- */
-enum {
- CDS_LFHT_AUTO_RESIZE = (1U << 0),
- CDS_LFHT_ACCOUNTING = (1U << 1),
-};
-
-/*
- * _cds_lfht_new - API used by cds_lfht_new wrapper. Do not use directly.
- */
-struct cds_lfht *_cds_lfht_new(cds_lfht_hash_fct hash_fct,
- cds_lfht_compare_fct compare_fct,
- unsigned long hash_seed,
- unsigned long init_size,
- unsigned long min_alloc_size,
- int flags,
- void (*cds_lfht_call_rcu)(struct rcu_head *head,
- void (*func)(struct rcu_head *head)),
- void (*cds_lfht_synchronize_rcu)(void),
- void (*cds_lfht_rcu_read_lock)(void),
- void (*cds_lfht_rcu_read_unlock)(void),
- void (*cds_lfht_rcu_thread_offline)(void),
- void (*cds_lfht_rcu_thread_online)(void),
- void (*cds_lfht_rcu_register_thread)(void),
- void (*cds_lfht_rcu_unregister_thread)(void),
- pthread_attr_t *attr);
-
-/*
- * cds_lfht_new - allocate a hash table.
- * @hash_fct: the hashing function.
- * @compare_fct: the key comparison function.
- * @hash_seed: the seed for hash function.
- * @init_size: number of nodes to allocate initially. Must be power of two.
- * @min_alloc_size: the smallest allocation size to use. Must be power of two.
- * @flags: hash table creation flags (can be combined with bitwise or: '|').
- * 0: no flags.
- * CDS_LFHT_AUTO_RESIZE: automatically resize hash table.
- * @attr: optional resize worker thread attributes. NULL for default.
- *
- * Return NULL on error.
- * Note: the RCU flavor must be already included before the hash table header.
- *
- * The programmer is responsible for ensuring that resize operation has a
- * priority equal to hash table updater threads. It should be performed by
- * specifying the appropriate priority in the pthread "attr" argument, and,
- * for CDS_LFHT_AUTO_RESIZE, by ensuring that call_rcu worker threads also have
- * this priority level. Having lower priority for call_rcu and resize threads
- * does not pose any correctness issue, but the resize operations could be
- * starved by updates, thus leading to long hash table bucket chains.
- * Threads calling this API need to be registered RCU read-side threads.
- */
-static inline
-struct cds_lfht *cds_lfht_new(cds_lfht_hash_fct hash_fct,
- cds_lfht_compare_fct compare_fct,
- unsigned long hash_seed,
- unsigned long init_size,
- unsigned long min_alloc_size,
- int flags,
- pthread_attr_t *attr)
-{
- return _cds_lfht_new(hash_fct, compare_fct, hash_seed,
- init_size, min_alloc_size, flags,
- call_rcu, synchronize_rcu, rcu_read_lock,
- rcu_read_unlock, rcu_thread_offline,
- rcu_thread_online, rcu_register_thread,
- rcu_unregister_thread, attr);
-}
-
-/*
- * cds_lfht_destroy - destroy a hash table.
- * @ht: the hash table to destroy.
- * @attr: (output) resize worker thread attributes, as received by cds_lfht_new.
- * The caller will typically want to free this pointer if dynamically
- * allocated. The attr point can be NULL if the caller does not
- * need to be informed of the value passed to cds_lfht_new().
- *
- * Return 0 on success, negative error value on error.
- * Threads calling this API need to be registered RCU read-side threads.
- */
-int cds_lfht_destroy(struct cds_lfht *ht, pthread_attr_t **attr);
-
-/*
- * cds_lfht_count_nodes - count the number of nodes in the hash table.
- * @ht: the hash table.
- * @split_count_before: Sample the node count split-counter before traversal.
- * @count: Traverse the hash table, count the number of nodes observed.
- * @removed: Number of logically removed nodes observed during traversal.
- * @split_count_after: Sample the node count split-counter after traversal.
- * Call with rcu_read_lock held.
- * Threads calling this API need to be registered RCU read-side threads.
- */
-void cds_lfht_count_nodes(struct cds_lfht *ht,
- long *split_count_before,
- unsigned long *count,
- unsigned long *removed,
- long *split_count_after);
-
-/*
- * cds_lfht_lookup - lookup a node by key.
- *
- * Output in "*iter". *iter->node set to NULL if not found.
- * Call with rcu_read_lock held.
- * Threads calling this API need to be registered RCU read-side threads.
- */
-void cds_lfht_lookup(struct cds_lfht *ht, void *key, size_t key_len,
- struct cds_lfht_iter *iter);
-
-/*
- * cds_lfht_next_duplicate - get the next item with same key (after a lookup).
- *
- * Uses an iterator initialized by a lookup.
- * Sets *iter-node to the following node with same key.
- * Sets *iter->node to NULL if no following node exists with same key.
- * RCU read-side lock must be held across cds_lfht_lookup and
- * cds_lfht_next calls, and also between cds_lfht_next calls using the
- * node returned by a previous cds_lfht_next.
- * Call with rcu_read_lock held.
- * Threads calling this API need to be registered RCU read-side threads.
- */
-void cds_lfht_next_duplicate(struct cds_lfht *ht, struct cds_lfht_iter *iter);
-
-/*
- * cds_lfht_first - get the first node in the table.
- *
- * Output in "*iter". *iter->node set to NULL if table is empty.
- * Call with rcu_read_lock held.
- * Threads calling this API need to be registered RCU read-side threads.
- */
-void cds_lfht_first(struct cds_lfht *ht, struct cds_lfht_iter *iter);
-
-/*
- * cds_lfht_next - get the next node in the table.
- *
- * Input/Output in "*iter". *iter->node set to NULL if *iter was
- * pointing to the last table node.
- * Call with rcu_read_lock held.
- * Threads calling this API need to be registered RCU read-side threads.
- */
-void cds_lfht_next(struct cds_lfht *ht, struct cds_lfht_iter *iter);
-
-/*
- * cds_lfht_add - add a node to the hash table.
- *
- * This function supports adding redundant keys into the table.
- * Call with rcu_read_lock held.
- * Threads calling this API need to be registered RCU read-side threads.
- */
-void cds_lfht_add(struct cds_lfht *ht, struct cds_lfht_node *node);
-
-/*
- * cds_lfht_add_unique - add a node to hash table, if key is not present.
- *
- * Return the node added upon success.
- * Return the unique node already present upon failure. If
- * cds_lfht_add_unique fails, the node passed as parameter should be
- * freed by the caller.
- * Call with rcu_read_lock held.
- * Threads calling this API need to be registered RCU read-side threads.
- *
- * The semantic of this function is that if only this function is used
- * to add keys into the table, no duplicated keys should ever be
- * observable in the table. The same guarantee apply for combination of
- * add_unique and add_replace (see below).
- */
-struct cds_lfht_node *cds_lfht_add_unique(struct cds_lfht *ht,
- struct cds_lfht_node *node);
-
-/*
- * cds_lfht_add_replace - replace or add a node within hash table.
- *
- * Return the node replaced upon success. If no node matching the key
- * was present, return NULL, which also means the operation succeeded.
- * This replacement operation should never fail.
- * Call with rcu_read_lock held.
- * Threads calling this API need to be registered RCU read-side threads.
- * After successful replacement, a grace period must be waited for before
- * freeing the memory reserved for the returned node.
- *
- * The semantic of replacement vs lookups is the following: if lookups
- * are performed between a key unique insertion and its removal, we
- * guarantee that the lookups and get next will always find exactly one
- * instance of the key if it is replaced concurrently with the lookups.
- *
- * Providing this semantic allows us to ensure that replacement-only
- * schemes will never generate duplicated keys. It also allows us to
- * guarantee that a combination of add_replace and add_unique updates
- * will never generate duplicated keys.
- */
-struct cds_lfht_node *cds_lfht_add_replace(struct cds_lfht *ht,
- struct cds_lfht_node *node);
-
-/*
- * cds_lfht_replace - replace a node pointer to by iter within hash table.
- *
- * Return 0 if replacement is successful, negative value otherwise.
- * Replacing a NULL old node or an already removed node will fail with a
- * negative value.
- * Old node can be looked up with cds_lfht_lookup and cds_lfht_next.
- * RCU read-side lock must be held between lookup and replacement.
- * Call with rcu_read_lock held.
- * Threads calling this API need to be registered RCU read-side threads.
- * After successful replacement, a grace period must be waited for before
- * freeing the memory reserved for the old node (which can be accessed
- * with cds_lfht_iter_get_node).
- *
- * The semantic of replacement vs lookups is the following: if lookups
- * are performed between a key unique insertion and its removal, we
- * guarantee that the lookups and get next will always find exactly one
- * instance of the key if it is replaced concurrently with the lookups.
- *
- * Providing this semantic allows us to ensure that replacement-only
- * schemes will never generate duplicated keys. It also allows us to
- * guarantee that a combination of add_replace and add_unique updates
- * will never generate duplicated keys.
- */
-int cds_lfht_replace(struct cds_lfht *ht, struct cds_lfht_iter *old_iter,
- struct cds_lfht_node *new_node);
-
-/*
- * cds_lfht_del - remove node pointed to by iterator from hash table.
- *
- * Return 0 if the node is successfully removed, negative value
- * otherwise.
- * Replacing a NULL node or an already removed node will fail with a
- * negative value.
- * Node can be looked up with cds_lfht_lookup and cds_lfht_next.
- * cds_lfht_iter_get_node.
- * RCU read-side lock must be held between lookup and removal.
- * Call with rcu_read_lock held.
- * Threads calling this API need to be registered RCU read-side threads.
- * After successful removal, a grace period must be waited for before
- * freeing the memory reserved for old node (which can be accessed with
- * cds_lfht_iter_get_node).
- */
-int cds_lfht_del(struct cds_lfht *ht, struct cds_lfht_iter *iter);
-
-/*
- * cds_lfht_resize - Force a hash table resize
- * @new_size: update to this hash table size.
- *
- * Threads calling this API need to be registered RCU read-side threads.
- */
-void cds_lfht_resize(struct cds_lfht *ht, unsigned long new_size);
-
-/*
- * Note: cds_lfht_for_each are safe for element removal during
- * iteration.
- */
-#define cds_lfht_for_each(ht, iter, node) \
- for (cds_lfht_first(ht, iter), \
- node = cds_lfht_iter_get_node(iter); \
- node != NULL; \
- cds_lfht_next(ht, iter), \
- node = cds_lfht_iter_get_node(iter))
-
-#define cds_lfht_for_each_duplicate(ht, match, hash, key, iter, node) \
- for (cds_lfht_lookup(ht, match, hash, key, iter), \
- node = cds_lfht_iter_get_node(iter); \
- node != NULL; \
- cds_lfht_next_duplicate(ht, match, key, iter), \
- node = cds_lfht_iter_get_node(iter))
-
-#define cds_lfht_for_each_entry(ht, iter, pos, member) \
- for (cds_lfht_first(ht, iter), \
- pos = caa_container_of(cds_lfht_iter_get_node(iter), \
- typeof(*(pos)), member); \
- &(pos)->member != NULL; \
- cds_lfht_next(ht, iter), \
- pos = caa_container_of(cds_lfht_iter_get_node(iter), \
- typeof(*(pos)), member))
-
-#define cds_lfht_for_each_entry_duplicate(ht, match, hash, key, \
- iter, pos, member) \
-for (cds_lfht_lookup(ht, match, hash, key, iter), \
- pos = caa_container_of(cds_lfht_iter_get_node(iter), \
- typeof(*(pos)), member); \
- &(pos)->member != NULL; \
- cds_lfht_next_duplicate(ht, match, key, iter), \
- pos = caa_container_of(cds_lfht_iter_get_node(iter), \
- typeof(*(pos)), member))
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* _URCU_RCULFHASH_H */
endif
lttng_sessiond_SOURCES = utils.c utils.h \
- hashtable.c hashtable.h \
compat/poll.h $(COMPAT) \
trace-kernel.c trace-kernel.h \
kernel.c kernel.h \
futex.c futex.h \
shm.c shm.h \
session.c session.h \
- lttng-ust-ctl.h lttng-ust-abi.h \
- ../hashtable/rculfhash.c \
- ../hashtable/rculfhash.h \
- ../hashtable/hash.c ../hashtable/hash.h
+ lttng-ust-ctl.h lttng-ust-abi.h
if HAVE_LIBLTTNG_UST_CTL
lttng_sessiond_SOURCES += trace-ust.c ust-app.c ust-consumer.c ust-consumer.h
$(top_builddir)/liblttng-sessiond-comm/liblttng-sessiond-comm.la \
$(top_builddir)/libkernelctl/libkernelctl.la \
$(top_builddir)/liblttngctl/liblttngctl.la \
- $(top_builddir)/librunas/librunas.la
+ $(top_builddir)/librunas/librunas.la \
+ $(top_builddir)/common/libcommon.la
if HAVE_LIBLTTNG_UST_CTL
lttng_sessiond_LDADD += -llttng-ust-ctl
#include <lttngerr.h>
#include "channel.h"
-#include "hashtable.h"
+#include "../common/hashtable.h"
#include "kernel.h"
#include "ust-ctl.h"
#include "utils.h"
#include <lttngerr.h>
#include "context.h"
-#include "hashtable.h"
+#include "../common/hashtable.h"
#include "kernel.h"
#include "ust-app.h"
#include "trace-ust.h"
#include "channel.h"
#include "event.h"
-#include "hashtable.h"
+#include "../common/hashtable.h"
#include "kernel.h"
#include "ust-ctl.h"
#include "ust-app.h"
+++ /dev/null
-/*
- * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the Free
- * Software Foundation; only version 2 of the License.
- *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
- * Place - Suite 330, Boston, MA 02111-1307, USA.
- */
-
-#include <urcu.h>
-
-#include <lttng-share.h>
-
-#include "hashtable.h"
-#include "../hashtable/rculfhash.h"
-#include "../hashtable/hash.h"
-
-struct cds_lfht *hashtable_new(unsigned long size)
-{
- if (size == 0) {
- size = DEFAULT_HT_SIZE;
- }
-
- return cds_lfht_new(hash_key, hash_compare_key, 0x42UL,
- size, size, CDS_LFHT_AUTO_RESIZE, NULL);
-}
-
-struct cds_lfht *hashtable_new_str(unsigned long size)
-{
- if (size == 0) {
- size = DEFAULT_HT_SIZE;
- }
-
- return cds_lfht_new(hash_key_str, hash_compare_key_str, 0x42UL,
- size, size, CDS_LFHT_AUTO_RESIZE, NULL);
-}
-
-struct cds_lfht_node *hashtable_iter_get_node(struct cds_lfht_iter *iter)
-{
- /* Safety net */
- if (iter == NULL) {
- return NULL;
- }
-
- return cds_lfht_iter_get_node(iter);
-}
-
-struct cds_lfht_node *hashtable_lookup(struct cds_lfht *ht, void *key,
- size_t key_len, struct cds_lfht_iter *iter)
-{
- /* Safety net */
- if (ht == NULL || iter == NULL || key == NULL) {
- return NULL;
- }
-
- cds_lfht_lookup(ht, key, key_len, iter);
-
- return hashtable_iter_get_node(iter);
-}
-
-void hashtable_get_first(struct cds_lfht *ht, struct cds_lfht_iter *iter)
-{
- cds_lfht_first(ht, iter);
-}
-
-void hashtable_get_next(struct cds_lfht *ht, struct cds_lfht_iter *iter)
-{
- cds_lfht_next(ht, iter);
-}
-
-void hashtable_add_unique(struct cds_lfht *ht, struct cds_lfht_node *node)
-{
- cds_lfht_add_unique(ht, node);
-}
-
-void hashtable_node_init(struct cds_lfht_node *node, void *key,
- size_t key_len)
-{
- cds_lfht_node_init(node, key, key_len);
-}
-
-int hashtable_del(struct cds_lfht *ht, struct cds_lfht_iter *iter)
-{
- /* Safety net */
- if (ht == NULL || iter == NULL) {
- return -1;
- }
-
- return cds_lfht_del(ht, iter);
-}
-
-unsigned long hashtable_get_count(struct cds_lfht *ht)
-{
- long ab, aa;
- unsigned long count, removed;
-
- cds_lfht_count_nodes(ht, &ab, &count, &removed, &aa);
-
- return count;
-}
-
-int hashtable_destroy(struct cds_lfht *ht)
-{
- return cds_lfht_destroy(ht, NULL);
-}
+++ /dev/null
-/*
- * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the Free
- * Software Foundation; only version 2 of the License.
- *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
- * Place - Suite 330, Boston, MA 02111-1307, USA.
- */
-
-#ifndef _LTT_HASHTABLE_H
-#define _LTT_HASHTABLE_H
-
-#include <urcu.h>
-#include "../hashtable/rculfhash.h"
-
-struct cds_lfht *hashtable_new(unsigned long size);
-struct cds_lfht *hashtable_new_str(unsigned long size);
-
-struct cds_lfht_node *hashtable_iter_get_node(struct cds_lfht_iter *iter);
-struct cds_lfht_node *hashtable_lookup(struct cds_lfht *ht, void *key,
- size_t key_len, struct cds_lfht_iter *iter);
-
-void hashtable_get_first(struct cds_lfht *ht, struct cds_lfht_iter *iter);
-void hashtable_get_next(struct cds_lfht *ht, struct cds_lfht_iter *iter);
-void hashtable_add_unique(struct cds_lfht *ht, struct cds_lfht_node *node);
-void hashtable_node_init(struct cds_lfht_node *node,
- void *key, size_t key_len);
-
-int hashtable_del(struct cds_lfht *ht, struct cds_lfht_iter *iter);
-unsigned long hashtable_get_count(struct cds_lfht *ht);
-int hashtable_destroy(struct cds_lfht *ht);
-
-#endif /* _LTT_HASHTABLE_H */
#include "context.h"
#include "event.h"
#include "futex.h"
-#include "hashtable.h"
+#include "../common/hashtable.h"
#include "kernel.h"
#include "lttng-sessiond.h"
#include "shm.h"
#include <lttngerr.h>
#include <runas.h>
-#include "hashtable.h"
+#include "../common/hashtable.h"
#include "session.h"
-#include "../hashtable/hash.h"
-
/*
* NOTES:
*
#include <lttngerr.h>
#include <lttng-share.h>
-#include "hashtable.h"
+#include "../common/hashtable.h"
#include "trace-ust.h"
/*
#include "ust-ctl.h"
-#include "../hashtable/rculfhash.h"
+#include "../common/hashtable.h"
/* UST Stream list */
struct ltt_ust_stream_list {
#include <lttng-share.h>
#include <runas.h>
-#include "hashtable.h"
+#include "../common/hashtable.h"
#include "ust-app.h"
#include "ust-consumer.h"
#include "ust-ctl.h"
#include <lttng-sessiond-comm.h>
#include <lttng/lttng-consumer.h>
-#include "hashtable.h"
+#include "../common/hashtable.h"
#include "ust-consumer.h"
/*
kernel_event_basic
UTILS=utils.h
-SESSIONS=$(top_srcdir)/lttng-sessiond/session.c $(top_srcdir)/lttng-sessiond/hashtable.c \
- $(top_srcdir)/hashtable/rculfhash.c $(top_srcdir)/hashtable/hash.c
+SESSIONS=$(top_srcdir)/lttng-sessiond/session.c
KERN_DATA_TRACE=$(top_srcdir)/lttng-sessiond/trace-kernel.c
LIBLTTNG=$(top_srcdir)/liblttngctl/lttngctl.c \
$(top_srcdir)/liblttng-sessiond-comm/lttng-sessiond-comm.c
test_sessions_SOURCES = test_sessions.c $(UTILS) $(SESSIONS)
-test_sessions_LDADD = $(top_builddir)/librunas/librunas.la
+test_sessions_LDADD = $(top_builddir)/common/libcommon.la $(top_builddir)/librunas/librunas.la
test_kernel_data_trace_SOURCES = test_kernel_data_trace.c $(UTILS) $(KERN_DATA_TRACE)
projects / lttng-tools.git / commitdiff
