X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Fconsumer-metadata-cache.c;h=6774692316a6dc4fe1b3e1a0fdf33d09fbc0c960;hp=5967a8eb296a51041f754622f65bb0b706ffe393;hb=b1325effaf300e21bb804113cc202b0e42ea61da;hpb=ec6ea7d01adc8a9d1481ba645b282c92ec27208e

diff --git a/src/common/consumer-metadata-cache.c b/src/common/consumer-metadata-cache.c
index 5967a8eb2..677469231 100644
--- a/src/common/consumer-metadata-cache.c
+++ b/src/common/consumer-metadata-cache.c
@@ -17,6 +17,7 @@
  */
 
 #define _GNU_SOURCE
+#define _LGPL_SOURCE
 #include <assert.h>
 #include <pthread.h>
 #include <stdlib.h>
@@ -46,14 +47,13 @@ static int extend_metadata_cache(struct lttng_consumer_channel *channel,
 {
 	int ret = 0;
 	char *tmp_data_ptr;
-	unsigned int new_size;
+	unsigned int new_size, old_size;
 
 	assert(channel);
 	assert(channel->metadata_cache);
 
-	new_size = max_t(unsigned int,
-			channel->metadata_cache->cache_alloc_size + size,
-			channel->metadata_cache->cache_alloc_size << 1);
+	old_size = channel->metadata_cache->cache_alloc_size;
+	new_size = max_t(unsigned int, old_size + size, old_size << 1);
 	DBG("Extending metadata cache to %u", new_size);
 	tmp_data_ptr = realloc(channel->metadata_cache->data, new_size);
 	if (!tmp_data_ptr) {
@@ -62,6 +62,8 @@ static int extend_metadata_cache(struct lttng_consumer_channel *channel,
 		ret = -1;
 		goto end;
 	}
+	/* Zero newly allocated memory */
+	memset(tmp_data_ptr + old_size, 0, new_size - old_size);
 	channel->metadata_cache->data = tmp_data_ptr;
 	channel->metadata_cache->cache_alloc_size = new_size;
 
@@ -71,8 +73,8 @@ end:
 
 /*
  * Write metadata to the cache, extend the cache if necessary. We support
- * non-contiguous updates but not overlapping ones. If there is contiguous
- * metadata in the cache, we send it to the ring buffer. The metadata cache
+ * overlapping updates, but they need to be contiguous. Send the
+ * contiguous metadata in cache to the ring buffer. The metadata cache
  * lock MUST be acquired to write in the cache.
  *
  * Return 0 on success, a negative value on error.
@@ -81,6 +83,7 @@ int consumer_metadata_cache_write(struct lttng_consumer_channel *channel,
 		unsigned int offset, unsigned int len, char *data)
 {
 	int ret = 0;
+	int size_ret;
 	struct consumer_metadata_cache *cache;
 
 	assert(channel);
@@ -99,20 +102,16 @@ int consumer_metadata_cache_write(struct lttng_consumer_channel *channel,
 	}
 
 	memcpy(cache->data + offset, data, len);
-	cache->total_bytes_written += len;
 	if (offset + len > cache->max_offset) {
-		cache->max_offset = offset + len;
-	}
-
-	if (cache->max_offset == cache->total_bytes_written) {
 		char dummy = 'c';
 
-		cache->contiguous = cache->max_offset;
+		cache->max_offset = offset + len;
 		if (channel->monitor) {
-			ret = write(channel->metadata_stream->ust_metadata_poll_pipe[1],
+			size_ret = lttng_write(channel->metadata_stream->ust_metadata_poll_pipe[1],
 					&dummy, 1);
-			if (ret < 1) {
+			if (size_ret < 1) {
 				ERR("Wakeup UST metadata pipe");
+				ret = -1;
 				goto end;
 			}
 		}
@@ -190,7 +189,7 @@ void consumer_metadata_cache_destroy(struct lttng_consumer_channel *channel)
  * Return 0 if everything has been flushed, 1 if there is data not flushed.
  */
 int consumer_metadata_cache_flushed(struct lttng_consumer_channel *channel,
-		uint64_t offset)
+		uint64_t offset, int timer)
 {
 	int ret = 0;
 	struct lttng_consumer_stream *metadata_stream;
@@ -199,12 +198,15 @@ int consumer_metadata_cache_flushed(struct lttng_consumer_channel *channel,
 	assert(channel->metadata_cache);
 
 	/*
-	 * XXX This consumer_data.lock should eventually be replaced by
-	 * a channel lock. It protects metadata_stream read and endpoint
-	 * status check.
+	 * If not called from a timer handler, we have to take the
+	 * channel lock to be mutually exclusive with channel teardown.
+	 * Timer handler does not need to take this lock because it is
+	 * already synchronized by timer stop (and, more importantly,
+	 * taking this lock in a timer handler would cause a deadlock).
 	 */
-	pthread_mutex_lock(&consumer_data.lock);
-	pthread_mutex_lock(&channel->lock);
+	if (!timer) {
+		pthread_mutex_lock(&channel->lock);
+	}
 	pthread_mutex_lock(&channel->timer_lock);
 	pthread_mutex_lock(&channel->metadata_cache->lock);
 
@@ -229,8 +231,9 @@ int consumer_metadata_cache_flushed(struct lttng_consumer_channel *channel,
 
 	pthread_mutex_unlock(&channel->metadata_cache->lock);
 	pthread_mutex_unlock(&channel->timer_lock);
-	pthread_mutex_unlock(&channel->lock);
-	pthread_mutex_unlock(&consumer_data.lock);
+	if (!timer) {
+		pthread_mutex_unlock(&channel->lock);
+	}
 
 	return ret;
 }