X-Git-Url: http://git.efficios.com/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Flib%2Flttng-ctl%2Flttng-ctl.c;h=165fef4dc5c412392fe49daec62be947d4de3853;hp=f503fd1cbf42a25660a990d869c7adeb467cc823;hb=09b72f7aa737f46196db18bcdf3bc947a08c27a2;hpb=d9f484bc6f074842bc4ac3eab0127fe3aaa10909

diff --git a/src/lib/lttng-ctl/lttng-ctl.c b/src/lib/lttng-ctl/lttng-ctl.c
index f503fd1cb..165fef4dc 100644
--- a/src/lib/lttng-ctl/lttng-ctl.c
+++ b/src/lib/lttng-ctl/lttng-ctl.c
@@ -287,6 +287,50 @@ end:
 	return ret;
 }
 
+static int check_enough_available_memory(size_t num_bytes_requested_per_cpu)
+{
+	int ret;
+	long num_cpu;
+	size_t best_mem_info;
+	size_t num_bytes_requested_total;
+
+	/*
+	 * Get the number of CPU currently online to compute the amount of
+	 * memory needed to create a buffer for every CPU.
+	 */
+	num_cpu = sysconf(_SC_NPROCESSORS_ONLN);
+	if (num_cpu == -1) {
+		goto error;
+	}
+
+	num_bytes_requested_total = num_bytes_requested_per_cpu * num_cpu;
+
+	/*
+	 * Try to get the `MemAvail` field of `/proc/meminfo`. This is the most
+	 * reliable estimate we can get but it is only exposed by the kernel
+	 * since 3.14. (See Linux kernel commit:
+	 * 34e431b0ae398fc54ea69ff85ec700722c9da773)
+	 */
+	ret = utils_get_memory_available(&best_mem_info);
+	if (ret >= 0) {
+		goto success;
+	}
+
+	/*
+	 * As a backup plan, use `MemTotal` field of `/proc/meminfo`. This
+	 * is a sanity check for obvious user error.
+	 */
+	ret = utils_get_memory_total(&best_mem_info);
+	if (ret >= 0) {
+		goto success;
+	}
+
+error:
+	return -1;
+success:
+	return best_mem_info >= num_bytes_requested_total;
+}
+
 /*
  * Try connect to session daemon with sock_path.
  *
@@ -1475,6 +1519,7 @@ int lttng_enable_channel(struct lttng_handle *handle,
 		struct lttng_channel *in_chan)
 {
 	struct lttcomm_session_msg lsm;
+	size_t total_buffer_size_needed_per_cpu = 0;
 
 	/* NULL arguments are forbidden. No default values. */
 	if (handle == NULL || in_chan == NULL) {
@@ -1510,6 +1555,16 @@ int lttng_enable_channel(struct lttng_handle *handle,
 		memcpy(&lsm.u.channel.extended, extended, sizeof(*extended));
 	}
 
+	/*
+	 * Verify that the amount of memory required to create the requested
+	 * buffer is available on the system at the moment.
+	 */
+	total_buffer_size_needed_per_cpu = lsm.u.channel.chan.attr.num_subbuf *
+		lsm.u.channel.chan.attr.subbuf_size;
+	if (!check_enough_available_memory(total_buffer_size_needed_per_cpu)) {
+		return -LTTNG_ERR_NOMEM;
+	}
+
 	lsm.cmd_type = LTTNG_ENABLE_CHANNEL;
 	lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
 
@@ -2039,7 +2094,6 @@ int lttng_list_events(struct lttng_handle *handle,
 
 			probe_storage_req = ret;
 			comm_ext_at += ext_comm->userspace_probe_location_len;
-			ret = 0;
 		}
 
 		storage_req += sizeof(struct lttng_event_extended);
@@ -2115,6 +2169,7 @@ int lttng_list_events(struct lttng_handle *handle,
 					ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN);
 			if (ret) {
 				ret = -LTTNG_ERR_NOMEM;
+				goto free_dynamic_buffer;
 			}
 			comm_ext_at += ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
 		}
@@ -2744,6 +2799,9 @@ int lttng_list_tracker_pids(struct lttng_handle *handle,
 		return ret;
 	}
 	nr_pids = ret / sizeof(int32_t);
+	if (nr_pids > 0 && !pids) {
+		return -LTTNG_ERR_UNK;
+	}
 	if (nr_pids == 1 && pids[0] == -1) {
 		free(pids);
 		pids = NULL;
@@ -2890,50 +2948,6 @@ end:
 	return ret;
 }
 
-int lttng_session_get_current_archive_location(const char *session_name,
-		char **chunk_path)
-{
-	struct lttcomm_session_msg lsm;
-	struct lttng_session_get_current_output_return *output_return = NULL;
-	int ret;
-	size_t path_len;
-
-	memset(&lsm, 0, sizeof(lsm));
-	lsm.cmd_type = LTTNG_SESSION_GET_CURRENT_OUTPUT;
-	ret = lttng_strncpy(lsm.session.name, session_name,
-			sizeof(lsm.session.name));
-	if (ret) {
-		ret = -LTTNG_ERR_INVALID;
-		goto end;
-	}
-
-	ret = lttng_ctl_ask_sessiond(&lsm, (void **) &output_return);
-	if (ret < 0) {
-		ret = -1;
-		goto end;
-	}
-
-	path_len = lttng_strnlen(output_return->path,
-			sizeof(output_return->path));
-	if (path_len == 0 || path_len == sizeof(output_return->path)) {
-		ret = -LTTNG_ERR_NO_SESSION_OUTPUT;
-		goto end;
-	}
-
-	*chunk_path = zmalloc(path_len + 1);
-	if (!*chunk_path) {
-		ret = -1;
-		goto end;
-	}
-	memcpy(*chunk_path, output_return->path, path_len);
-
-	ret = 0;
-
-end:
-	free(output_return);
-	return ret;
-}
-
 /*
  * lib constructor.
  */