X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fkernel.c;h=e5f068a0cd9515408a34b4621201e8b75f714a81;hb=4f5fb4c3d8752aae822ed0066784cc77e6f0f508;hp=abf038f4d59a3f1c9f021123e29e947db3fd4db1;hpb=21ed98c107c9be59bd1f4e2b2b1ecfb56ef6ff57;p=lttng-tools.git

diff --git a/src/bin/lttng-sessiond/kernel.c b/src/bin/lttng-sessiond/kernel.c
index abf038f4d..e5f068a0c 100644
--- a/src/bin/lttng-sessiond/kernel.c
+++ b/src/bin/lttng-sessiond/kernel.c
@@ -34,8 +34,16 @@
 #include "kern-modules.h"
 #include "utils.h"
 
+/*
+ * Key used to reference a channel between the sessiond and the consumer. This
+ * is only read and updated with the session_list lock held.
+ */
+static uint64_t next_kernel_channel_key;
+
 /*
  * Add context on a kernel channel.
+ *
+ * Assumes the ownership of ctx.
  */
 int kernel_add_channel_context(struct ltt_kernel_channel *chan,
 		struct ltt_kernel_context *ctx)
@@ -67,7 +75,12 @@ int kernel_add_channel_context(struct ltt_kernel_channel *chan,
 
 end:
 	cds_list_add_tail(&ctx->list, &chan->ctx_list);
+	ctx->in_list = true;
+	ctx = NULL;
 error:
+	if (ctx) {
+		trace_kernel_destroy_context(ctx);
+	}
 	return ret;
 }
 
@@ -162,8 +175,10 @@ int kernel_create_channel(struct ltt_kernel_session *session,
 	cds_list_add(&lkc->list, &session->channel_list.head);
 	session->channel_count++;
 	lkc->session = session;
+	lkc->key = ++next_kernel_channel_key;
 
-	DBG("Kernel channel %s created (fd: %d)", lkc->channel->name, lkc->fd);
+	DBG("Kernel channel %s created (fd: %d, key: %" PRIu64 ")",
+			lkc->channel->name, lkc->fd, lkc->key);
 
 	return 0;
 
@@ -284,7 +299,8 @@ int kernel_disable_channel(struct ltt_kernel_channel *chan)
 	}
 
 	chan->enabled = 0;
-	DBG("Kernel channel %s disabled (fd: %d)", chan->channel->name, chan->fd);
+	DBG("Kernel channel %s disabled (fd: %d, key: %" PRIu64 ")",
+			chan->channel->name, chan->fd, chan->key);
 
 	return 0;
 
@@ -308,7 +324,8 @@ int kernel_enable_channel(struct ltt_kernel_channel *chan)
 	}
 
 	chan->enabled = 1;
-	DBG("Kernel channel %s enabled (fd: %d)", chan->channel->name, chan->fd);
+	DBG("Kernel channel %s enabled (fd: %d, key: %" PRIu64 ")",
+			chan->channel->name, chan->fd, chan->key);
 
 	return 0;
 
@@ -518,6 +535,7 @@ int kernel_open_metadata(struct ltt_kernel_session *session)
 	}
 
 	lkm->fd = ret;
+	lkm->key = ++next_kernel_channel_key;
 	/* Prevent fd duplication after execlp() */
 	ret = fcntl(lkm->fd, F_SETFD, FD_CLOEXEC);
 	if (ret < 0) {
@@ -807,38 +825,38 @@ error:
 /*
  * Get kernel version and validate it.
  */
-int kernel_validate_version(int tracer_fd)
+int kernel_validate_version(int tracer_fd,
+		struct lttng_kernel_tracer_version *version,
+		struct lttng_kernel_tracer_abi_version *abi_version)
 {
 	int ret;
-	struct lttng_kernel_tracer_version version;
-	struct lttng_kernel_tracer_abi_version abi_version;
 
-	ret = kernctl_tracer_version(tracer_fd, &version);
+	ret = kernctl_tracer_version(tracer_fd, version);
 	if (ret < 0) {
 		ERR("Failed to retrieve the lttng-modules version");
 		goto error;
 	}
 
 	/* Validate version */
-	if (version.major != VERSION_MAJOR) {
+	if (version->major != VERSION_MAJOR) {
 		ERR("Kernel tracer major version (%d) is not compatible with lttng-tools major version (%d)",
-			version.major, VERSION_MAJOR);
+			version->major, VERSION_MAJOR);
 		goto error_version;
 	}
-	ret = kernctl_tracer_abi_version(tracer_fd, &abi_version);
+	ret = kernctl_tracer_abi_version(tracer_fd, abi_version);
 	if (ret < 0) {
 		ERR("Failed to retrieve lttng-modules ABI version");
 		goto error;
 	}
-	if (abi_version.major != LTTNG_MODULES_ABI_MAJOR_VERSION) {
+	if (abi_version->major != LTTNG_MODULES_ABI_MAJOR_VERSION) {
 		ERR("Kernel tracer ABI version (%d.%d) does not match the expected ABI major version (%d.*)",
-			abi_version.major, abi_version.minor,
+			abi_version->major, abi_version->minor,
 			LTTNG_MODULES_ABI_MAJOR_VERSION);
 		goto error;
 	}
 	DBG2("Kernel tracer version validated (%d.%d, ABI %d.%d)",
-			version.major, version.minor,
-			abi_version.major, abi_version.minor);
+			version->major, version->minor,
+			abi_version->major, abi_version->minor);
 	return 0;
 
 error_version:
@@ -1022,12 +1040,10 @@ int kernel_snapshot_record(struct ltt_kernel_session *ksess,
 
 		/* For each channel, ask the consumer to snapshot it. */
 		cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
-			pthread_mutex_lock(socket->lock);
-			ret = consumer_snapshot_channel(socket, chan->fd, output, 0,
+			ret = consumer_snapshot_channel(socket, chan->key, output, 0,
 					ksess->uid, ksess->gid,
 					DEFAULT_KERNEL_TRACE_DIR, wait,
 					nb_packets_per_stream);
-			pthread_mutex_unlock(socket->lock);
 			if (ret < 0) {
 				ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
 				(void) kernel_consumer_destroy_metadata(socket,
@@ -1037,11 +1053,9 @@ int kernel_snapshot_record(struct ltt_kernel_session *ksess,
 		}
 
 		/* Snapshot metadata, */
-		pthread_mutex_lock(socket->lock);
-		ret = consumer_snapshot_channel(socket, ksess->metadata->fd, output,
+		ret = consumer_snapshot_channel(socket, ksess->metadata->key, output,
 				1, ksess->uid, ksess->gid,
 				DEFAULT_KERNEL_TRACE_DIR, wait, 0);
-		pthread_mutex_unlock(socket->lock);
 		if (ret < 0) {
 			ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
 			goto error_consumer;