From ab7d5fc6ff3128b5699e1871e9726f4e79b8f2e6 Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Sun, 27 Sep 2009 00:02:21 -0400 Subject: [PATCH] urcu-ht: work in progress RCU hash table Signed-off-by: Mathieu Desnoyers --- Makefile.inc | 2 +- tests/Makefile.inc | 6 +- tests/test_ht.c | 434 +++++++++++++++++++++++++++++++++++++++ urcu-hash.c => urcu-ht.c | 58 ++---- urcu-ht.h | 23 +++ 5 files changed, 485 insertions(+), 38 deletions(-) create mode 100644 tests/test_ht.c rename urcu-hash.c => urcu-ht.c (83%) create mode 100644 urcu-ht.h diff --git a/Makefile.inc b/Makefile.inc index 9d566b7..7a5ed3f 100644 --- a/Makefile.inc +++ b/Makefile.inc @@ -8,7 +8,7 @@ all: checkarch liburcu.so urcu.o \ liburcu-mb.so urcu-mb.o \ liburcu-defer.so urcu-defer.o \ urcu-yield.o \ - urcu-hash.o \ + urcu-ht.o \ subdirs checkarch: diff --git a/tests/Makefile.inc b/tests/Makefile.inc index f62256b..4e85352 100644 --- a/tests/Makefile.inc +++ b/tests/Makefile.inc @@ -16,6 +16,7 @@ URCU_SIGNAL_YIELD=${LIBDIR}/urcu-yield.o ${LIBDIR}/urcu.h URCU_MB=${LIBDIR}/urcu-mb.o ${LIBDIR}/urcu.h URCU_QSBR=${LIBDIR}/urcu-qsbr.o ${LIBDIR}/urcu-qsbr.h URCU_MB_DEFER=${LIBDIR}/urcu-mb.o ${LIBDIR}/urcu-defer.o ${LIBDIR}/urcu.h +URCU_HT=${LIBDIR}/urcu-mb.o ${LIBDIR}/urcu-defer.o ${LIBDIR}/urcu-ht.o ${LIBDIR}/urcu.h all: test_urcu test_urcu_dynamic_link test_urcu_timing \ test_rwlock_timing test_rwlock test_perthreadlock_timing \ @@ -24,7 +25,7 @@ all: test_urcu test_urcu_dynamic_link test_urcu_timing \ urcutorture-yield test_mutex test_looplen test_urcu_gc \ test_urcu_gc_mb test_qsbr_gc test_qsbr_lgc test_urcu_lgc \ test_urcu_lgc_mb test_qsbr_dynamic_link test_urcu_mb_defer \ - test_atomic + test_atomic test_ht api.h: ${APIHEADER} cp -f ${APIHEADER} api.h @@ -112,6 +113,9 @@ urcutorture-yield: urcutorture.c ${URCU_SIGNAL_YIELD} rcutorture.h api.h test_atomic: test_atomic.c ../arch_atomic.h $(CC) ${CFLAGS} $(LDFLAGS) -o $@ $(SRC_DEP) +test_ht: test_ht.c ${URCU_HT} + $(CC) ${CFLAGS} $(LDFLAGS) -o $@ $(SRC_DEP) + ,PHONY: clean clean: diff --git a/tests/test_ht.c b/tests/test_ht.c new file mode 100644 index 0000000..12b210e --- /dev/null +++ b/tests/test_ht.c @@ -0,0 +1,434 @@ +/* + * test_ht.c + * + * Userspace RCU library - test program + * + * Copyright February 2009 - Mathieu Desnoyers + * + * 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; either version 2 of the License, or + * (at your option) any later version. + * + * 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., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "../urcu-ht.h" + +#include "../arch.h" + +/* Make this big enough to include the POWER5+ L3 cacheline size of 256B */ +#define CACHE_LINE_SIZE 4096 + +/* hardcoded number of CPUs */ +#define NR_CPUS 16384 + +#if defined(_syscall0) +_syscall0(pid_t, gettid) +#elif defined(__NR_gettid) +static inline pid_t gettid(void) +{ + return syscall(__NR_gettid); +} +#else +#warning "use pid as tid" +static inline pid_t gettid(void) +{ + return getpid(); +} +#endif + +#ifndef DYNAMIC_LINK_TEST +#define _LGPL_SOURCE +#else +#define debug_yield_read() +#endif +#include "../urcu.h" + +static struct rcu_ht *test_ht; + +struct test_array { + int a; +}; + +static volatile int test_go, test_stop; + +static unsigned long wdelay; + +static struct test_array *test_rcu_pointer; + +static unsigned long duration; + +/* read-side C.S. duration, in loops */ +static unsigned long rduration; + +static inline void loop_sleep(unsigned long l) +{ + while(l-- != 0) + cpu_relax(); +} + +static int verbose_mode; + +#define printf_verbose(fmt, args...) \ + do { \ + if (verbose_mode) \ + printf(fmt, args); \ + } while (0) + +static unsigned int cpu_affinities[NR_CPUS]; +static unsigned int next_aff = 0; +static int use_affinity = 0; + +pthread_mutex_t affinity_mutex = PTHREAD_MUTEX_INITIALIZER; + +static void set_affinity(void) +{ + cpu_set_t mask; + int cpu; + int ret; + + if (!use_affinity) + return; + + ret = pthread_mutex_lock(&affinity_mutex); + if (ret) { + perror("Error in pthread mutex lock"); + exit(-1); + } + cpu = cpu_affinities[next_aff++]; + ret = pthread_mutex_unlock(&affinity_mutex); + if (ret) { + perror("Error in pthread mutex unlock"); + exit(-1); + } + CPU_ZERO(&mask); + CPU_SET(cpu, &mask); + sched_setaffinity(0, sizeof(mask), &mask); +} + +/* + * returns 0 if test should end. + */ +static int test_duration_write(void) +{ + return !test_stop; +} + +static int test_duration_read(void) +{ + return !test_stop; +} + +static unsigned long long __thread nr_writes; +static unsigned long long __thread nr_reads; + +static unsigned int nr_readers; +static unsigned int nr_writers; + +pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER; + +void rcu_copy_mutex_lock(void) +{ + int ret; + ret = pthread_mutex_lock(&rcu_copy_mutex); + if (ret) { + perror("Error in pthread mutex lock"); + exit(-1); + } +} + +void rcu_copy_mutex_unlock(void) +{ + int ret; + + ret = pthread_mutex_unlock(&rcu_copy_mutex); + if (ret) { + perror("Error in pthread mutex unlock"); + exit(-1); + } +} + +/* + * malloc/free are reusing memory areas too quickly, which does not let us + * test races appropriately. Use a large circular array for allocations. + * ARRAY_SIZE is larger than nr_writers, which insures we never run over our tail. + */ +#define ARRAY_SIZE (1048576 * nr_writers) +#define ARRAY_POISON 0xDEADBEEF +static int array_index; +static struct test_array *test_array; + +static struct test_array *test_array_alloc(void) +{ + struct test_array *ret; + int index; + + rcu_copy_mutex_lock(); + index = array_index % ARRAY_SIZE; + assert(test_array[index].a == ARRAY_POISON || + test_array[index].a == 0); + ret = &test_array[index]; + array_index++; + if (array_index == ARRAY_SIZE) + array_index = 0; + rcu_copy_mutex_unlock(); + return ret; +} + +static void test_array_free(struct test_array *ptr) +{ + if (!ptr) + return; + rcu_copy_mutex_lock(); + ptr->a = ARRAY_POISON; + rcu_copy_mutex_unlock(); +} + +void *thr_reader(void *_count) +{ + unsigned long long *count = _count; + struct test_array *local_ptr; + + printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n", + "reader", pthread_self(), (unsigned long)gettid()); + + set_affinity(); + + rcu_register_thread(); + + while (!test_go) + { + } + smp_mb(); + + for (;;) { + rcu_read_lock(); + local_ptr = rcu_dereference(test_rcu_pointer); + debug_yield_read(); + if (local_ptr) + assert(local_ptr->a == 8); + if (unlikely(rduration)) + loop_sleep(rduration); + rcu_read_unlock(); + nr_reads++; + if (unlikely(!test_duration_read())) + break; + } + + rcu_unregister_thread(); + + *count = nr_reads; + printf_verbose("thread_end %s, thread id : %lx, tid %lu\n", + "reader", pthread_self(), (unsigned long)gettid()); + return ((void*)1); + +} + +void *thr_writer(void *_count) +{ + unsigned long long *count = _count; + struct test_array *new, *old; + + printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n", + "writer", pthread_self(), (unsigned long)gettid()); + + set_affinity(); + + while (!test_go) + { + } + smp_mb(); + + for (;;) { + new = test_array_alloc(); + new->a = 8; + old = rcu_publish_content(&test_rcu_pointer, new); + if (old) + old->a = 0; + test_array_free(old); + nr_writes++; + if (unlikely(!test_duration_write())) + break; + if (unlikely(wdelay)) + loop_sleep(wdelay); + } + + printf_verbose("thread_end %s, thread id : %lx, tid %lu\n", + "writer", pthread_self(), (unsigned long)gettid()); + *count = nr_writes; + return ((void*)2); +} + +void show_usage(int argc, char **argv) +{ + printf("Usage : %s nr_readers nr_writers duration (s)", argv[0]); +#ifdef DEBUG_YIELD + printf(" [-r] [-w] (yield reader and/or writer)"); +#endif + printf(" [-d delay] (writer period (us))"); + printf(" [-c duration] (reader C.S. duration (in loops))"); + printf(" [-v] (verbose output)"); + printf(" [-a cpu#] [-a cpu#]... (affinity)"); + printf("\n"); +} + +int main(int argc, char **argv) +{ + int err; + pthread_t *tid_reader, *tid_writer; + void *tret; + unsigned long long *count_reader, *count_writer; + unsigned long long tot_reads = 0, tot_writes = 0; + int i, a; + + if (argc < 4) { + show_usage(argc, argv); + return -1; + } + + err = sscanf(argv[1], "%u", &nr_readers); + if (err != 1) { + show_usage(argc, argv); + return -1; + } + + err = sscanf(argv[2], "%u", &nr_writers); + if (err != 1) { + show_usage(argc, argv); + return -1; + } + + err = sscanf(argv[3], "%lu", &duration); + if (err != 1) { + show_usage(argc, argv); + return -1; + } + + for (i = 4; i < argc; i++) { + if (argv[i][0] != '-') + continue; + switch (argv[i][1]) { +#ifdef DEBUG_YIELD + case 'r': + yield_active |= YIELD_READ; + break; + case 'w': + yield_active |= YIELD_WRITE; + break; +#endif + case 'a': + if (argc < i + 2) { + show_usage(argc, argv); + return -1; + } + a = atoi(argv[++i]); + cpu_affinities[next_aff++] = a; + use_affinity = 1; + printf_verbose("Adding CPU %d affinity\n", a); + break; + case 'c': + if (argc < i + 2) { + show_usage(argc, argv); + return -1; + } + rduration = atol(argv[++i]); + break; + case 'd': + if (argc < i + 2) { + show_usage(argc, argv); + return -1; + } + wdelay = atol(argv[++i]); + break; + case 'v': + verbose_mode = 1; + break; + } + } + + printf_verbose("running test for %lu seconds, %u readers, %u writers.\n", + duration, nr_readers, nr_writers); + printf_verbose("Writer delay : %lu loops.\n", wdelay); + printf_verbose("Reader duration : %lu loops.\n", rduration); + printf_verbose("thread %-6s, thread id : %lx, tid %lu\n", + "main", pthread_self(), (unsigned long)gettid()); + + test_array = malloc(sizeof(*test_array) * ARRAY_SIZE); + tid_reader = malloc(sizeof(*tid_reader) * nr_readers); + tid_writer = malloc(sizeof(*tid_writer) * nr_writers); + count_reader = malloc(sizeof(*count_reader) * nr_readers); + count_writer = malloc(sizeof(*count_writer) * nr_writers); + test_ht = ht_new(stupid_hash, free); + next_aff = 0; + + for (i = 0; i < nr_readers; i++) { + err = pthread_create(&tid_reader[i], NULL, thr_reader, + &count_reader[i]); + if (err != 0) + exit(1); + } + for (i = 0; i < nr_writers; i++) { + err = pthread_create(&tid_writer[i], NULL, thr_writer, + &count_writer[i]); + if (err != 0) + exit(1); + } + + smp_mb(); + + test_go = 1; + + sleep(duration); + + test_stop = 1; + + for (i = 0; i < nr_readers; i++) { + err = pthread_join(tid_reader[i], &tret); + if (err != 0) + exit(1); + tot_reads += count_reader[i]; + } + for (i = 0; i < nr_writers; i++) { + err = pthread_join(tid_writer[i], &tret); + if (err != 0) + exit(1); + tot_writes += count_writer[i]; + } + ht_destroy(test_ht); + + printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads, + tot_writes); + printf("SUMMARY %-25s testdur %4lu nr_readers %3u rdur %6lu " + "nr_writers %3u " + "wdelay %6lu nr_reads %12llu nr_writes %12llu nr_ops %12llu\n", + argv[0], duration, nr_readers, rduration, + nr_writers, wdelay, tot_reads, tot_writes, + tot_reads + tot_writes); + test_array_free(test_rcu_pointer); + free(test_array); + free(tid_reader); + free(tid_writer); + free(count_reader); + free(count_writer); + return 0; +} diff --git a/urcu-hash.c b/urcu-ht.c similarity index 83% rename from urcu-hash.c rename to urcu-ht.c index 1267af5..8edfae3 100644 --- a/urcu-hash.c +++ b/urcu-ht.c @@ -8,10 +8,7 @@ #include #include #include - -#define HASH_SIZE 4096 - -typedef unsigned long (*ht_hash_fct)(void *key); +#include struct rcu_ht_node; @@ -27,28 +24,6 @@ struct rcu_ht { void (*free_fct)(void *data); /* fct to free data */ }; -struct rcu_ht *ht_new(ht_hash_fct hash_fct, void (*free_fct)(void *data)); - -void ht_delete_all(struct rcu_ht *ht); - -int ht_destroy(struct rcu_ht *ht); - -void *ht_lookup(struct rcu_ht *ht, void *key); - -int ht_add(struct rcu_ht *ht, void *key, void *data); - -int ht_delete(struct rcu_ht *ht, void *key); - -void *ht_steal(struct rcu_ht *ht, void *key); - - -/* Implementation */ - -static unsigned long stupid_hash(void *key) -{ - return (unsigned long)key % HASH_SIZE; -} - struct rcu_ht *ht_new(ht_hash_fct hash_fct, void (*free_fct)(void *data)) { struct rcu_ht *ht; @@ -56,6 +31,7 @@ struct rcu_ht *ht_new(ht_hash_fct hash_fct, void (*free_fct)(void *data)) ht = calloc(1, sizeof(struct rcu_ht)); ht->hash_fct = hash_fct; ht->free_fct = free_fct; + return ht; } /* delete all elements */ @@ -92,7 +68,7 @@ void ht_delete_all(struct rcu_ht *ht) * Should only be called when no more concurrent readers nor writers can * possibly access the table. */ -int ht_destroy(struct rcu_ht *ht) +void ht_destroy(struct rcu_ht *ht) { ht_delete_all(ht); free(ht); @@ -120,6 +96,8 @@ void *ht_lookup(struct rcu_ht *ht, void *key) node = rcu_dereference(node->next); } rcu_read_unlock(); + + return ret; } /* @@ -177,10 +155,11 @@ restart: * Restart until we successfully remove the entry, or no entry is left * ((void *)(unsigned long)-ENOENT). */ -struct rcu_ht_node *ht_steal(struct rcu_ht *ht, void *key); +void *ht_steal(struct rcu_ht *ht, void *key) { struct rcu_ht_node **prev, *node; unsigned long hash; + void *data; hash = ht->hash_fct(key); @@ -191,7 +170,7 @@ retry: node = rcu_dereference(*prev); for (;;) { if (likely(!node)) { - node = (void *)(unsigned long)-ENOENT; + data = (void *)(unsigned long)-ENOENT; goto end; } if (node->key == key) { @@ -206,7 +185,10 @@ retry: end: rcu_read_unlock(); - return node; + data = node->data; + call_rcu(free, node); + + return data; /* restart loop, release and re-take the read lock to be kind to GP */ restart: @@ -216,15 +198,19 @@ restart: int ht_delete(struct rcu_ht *ht, void *key) { - struct rcu_ht_node *node; + void *data; - node = ht_steal(ht, key); - if (node) { - if (free_fct && node->data) - call_rcu(ht->free_fct, node->data); - call_rcu(free, node); + data = ht_steal(ht, key); + if (data) { + if (ht->free_fct && data) + call_rcu(ht->free_fct, data); return 0; } else { return -ENOENT; } } + +unsigned long stupid_hash(void *key) +{ + return (unsigned long)key % HASH_SIZE; +} diff --git a/urcu-ht.h b/urcu-ht.h new file mode 100644 index 0000000..0cbd1e6 --- /dev/null +++ b/urcu-ht.h @@ -0,0 +1,23 @@ +#ifndef _URCU_HT_H +#define _URCU_HT_H + +#define HASH_SIZE 4096 +typedef unsigned long (*ht_hash_fct)(void *key); + +struct rcu_ht *ht_new(ht_hash_fct hash_fct, void (*free_fct)(void *data)); + +void ht_delete_all(struct rcu_ht *ht); + +void ht_destroy(struct rcu_ht *ht); + +void *ht_lookup(struct rcu_ht *ht, void *key); + +int ht_add(struct rcu_ht *ht, void *key, void *data); + +int ht_delete(struct rcu_ht *ht, void *key); + +void *ht_steal(struct rcu_ht *ht, void *key); + +unsigned long stupid_hash(void *key); + +#endif /* _URCU_HT_H */ -- 2.34.1