X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=libtracing%2Frelay.c;h=16f5322e1b7b7f42c7268c3374782ce7e3ea6926;hb=1ae7f0744f280e97ab1a2adc548b8fd9f2cb21a4;hp=d78fa72a7ae2ac248cc07e309ba1c48236fcfbc2;hpb=c1dea0b3d1312d0e3747da93eb949145c487eeba;p=lttng-ust.git

diff --git a/libtracing/relay.c b/libtracing/relay.c
index d78fa72a..16f5322e 100644
--- a/libtracing/relay.c
+++ b/libtracing/relay.c
@@ -22,8 +22,10 @@
 //ust// #include <linux/cpu.h>
 //ust// #include <linux/splice.h>
 //ust// #include <linux/bitops.h>
-#include <sys/mman.h>
 #include "kernelcompat.h"
+#include <sys/mman.h>
+#include <sys/ipc.h>
+#include <sys/shm.h>
 #include "list.h"
 #include "relay.h"
 #include "channels.h"
@@ -93,21 +95,45 @@ static int relay_alloc_buf(struct rchan_buf *buf, size_t *size)
 	unsigned int n_pages;
 	struct buf_page *buf_page, *n;
 
-	void *result;
+	void *ptr;
+	int result;
+	int shmid;
 
 	*size = PAGE_ALIGN(*size);
 
-	/* Maybe do read-ahead */
-	result = mmap(NULL, *size, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
-	if(result == MAP_FAILED) {
-		PERROR("mmap");
+	result = shmid = shmget(getpid(), *size, IPC_CREAT | IPC_EXCL | 0700);
+	if(shmid == -1) {
+		PERROR("shmget");
 		return -1;
 	}
 
-	buf->buf_data = result;
+	ptr = shmat(shmid, NULL, 0);
+	if(ptr == (void *) -1) {
+		perror("shmat");
+		goto destroy_shmem;
+	}
+
+	/* Already mark the shared memory for destruction. This will occur only
+         * when all users have detached.
+	 */
+	result = shmctl(shmid, IPC_RMID, NULL);
+	if(result == -1) {
+		perror("shmctl");
+		return -1;
+	}
+
+	buf->buf_data = ptr;
 	buf->buf_size = *size;
 
 	return 0;
+
+	destroy_shmem:
+	result = shmctl(shmid, IPC_RMID, NULL);
+	if(result == -1) {
+		perror("shmctl");
+	}
+
+	return -1;
 }
 
 /**
@@ -181,7 +207,7 @@ static void relay_destroy_buf(struct rchan_buf *buf)
 static void relay_remove_buf(struct kref *kref)
 {
 	struct rchan_buf *buf = container_of(kref, struct rchan_buf, kref);
-	buf->chan->cb->remove_buf_file(buf);
+//ust//	buf->chan->cb->remove_buf_file(buf);
 	relay_destroy_buf(buf);
 }
 
@@ -748,37 +774,6 @@ void *ltt_relay_offset_address(struct rchan_buf *buf, size_t offset)
 #define printk_dbg(fmt, args...)
 #endif
 
-/* LTTng lockless logging buffer info */
-struct ltt_channel_buf_struct {
-	/* First 32 bytes cache-hot cacheline */
-	local_t offset;			/* Current offset in the buffer */
-	local_t *commit_count;		/* Commit count per sub-buffer */
-	atomic_long_t consumed;		/*
-					 * Current offset in the buffer
-					 * standard atomic access (shared)
-					 */
-	unsigned long last_tsc;		/*
-					 * Last timestamp written in the buffer.
-					 */
-	/* End of first 32 bytes cacheline */
-	atomic_long_t active_readers;	/*
-					 * Active readers count
-					 * standard atomic access (shared)
-					 */
-	local_t events_lost;
-	local_t corrupted_subbuffers;
-	spinlock_t full_lock;		/*
-					 * buffer full condition spinlock, only
-					 * for userspace tracing blocking mode
-					 * synchronization with reader.
-					 */
-//ust//	wait_queue_head_t write_wait;	/*
-//ust//					 * Wait queue for blocking user space
-//ust//					 * writers
-//ust//					 */
-	atomic_t wakeup_readers;	/* Boolean : wakeup readers waiting ? */
-} ____cacheline_aligned;
-
 /*
  * Last TSC comparison functions. Check if the current TSC overflows
  * LTT_TSC_BITS bits from the last TSC read. Reads and writes last_tsc
@@ -1041,7 +1036,7 @@ static notrace void ltt_buf_unfull(struct rchan_buf *buf,
 //ust// 	return mask;
 //ust// }
 
-static int ltt_do_get_subbuf(struct rchan_buf *buf, struct ltt_channel_buf_struct *ltt_buf, long *pconsumed_old)
+int ltt_do_get_subbuf(struct rchan_buf *buf, struct ltt_channel_buf_struct *ltt_buf, long *pconsumed_old)
 {
 	struct ltt_channel_struct *ltt_channel = (struct ltt_channel_struct *)buf->chan->private_data;
 	long consumed_old, consumed_idx, commit_count, write_offset;
@@ -1081,7 +1076,7 @@ static int ltt_do_get_subbuf(struct rchan_buf *buf, struct ltt_channel_buf_struc
 	return 0;
 }
 
-static int ltt_do_put_subbuf(struct rchan_buf *buf, struct ltt_channel_buf_struct *ltt_buf, u32 uconsumed_old)
+int ltt_do_put_subbuf(struct rchan_buf *buf, struct ltt_channel_buf_struct *ltt_buf, u32 uconsumed_old)
 {
 	long consumed_new, consumed_old;
 
@@ -2375,9 +2370,14 @@ static struct ltt_transport ust_relay_transport = {
 //ust// 	return 0;
 //ust// }
 
-void init_ustrelay_transport(void)
+static char initialized = 0;
+
+void __attribute__((constructor)) init_ustrelay_transport(void)
 {
-	ltt_transport_register(&ust_relay_transport);
+	if(!initialized) {
+		ltt_transport_register(&ust_relay_transport);
+		initialized = 1;
+	}
 }
 
 static void __exit ltt_relay_exit(void)