From: David Goulet <david.goulet@polymtl.ca>
Date: Wed, 1 Jun 2011 21:29:21 +0000 (-0400)
Subject: Fix kconsumerd multiple spawn bug
X-Git-Tag: v2.0-pre1~93
X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=commitdiff_plain;h=c49dc785799508e445e3e386c87f8151eef3c34c

Fix kconsumerd multiple spawn bug

The kconsumerd thread was spawned even if there was already an existing
kconsumerd thread.

Signed-off-by: David Goulet <david.goulet@polymtl.ca>
---

diff --git a/ltt-sessiond/main.c b/ltt-sessiond/main.c
index 30b0edd0e..97db535d1 100644
--- a/ltt-sessiond/main.c
+++ b/ltt-sessiond/main.c
@@ -486,6 +486,8 @@ static pid_t spawn_kconsumerd(void)
 	int ret;
 	pid_t pid;
 
+	DBG("Spawning kconsumerd");
+
 	pid = fork();
 	if (pid == 0) {
 		/*
@@ -518,21 +520,21 @@ static int start_kconsumerd(void)
 {
 	int ret;
 
-	DBG("Spawning kconsumerd");
-
 	pthread_mutex_lock(&kconsumerd_pid_mutex);
-	if (kconsumerd_pid == 0) {
-		ret = spawn_kconsumerd();
-		if (ret < 0) {
-			ERR("Spawning kconsumerd failed");
-			ret = LTTCOMM_KERN_CONSUMER_FAIL;
-			pthread_mutex_unlock(&kconsumerd_pid_mutex);
-			goto error;
-		}
+	if (kconsumerd_pid != 0) {
+		goto end;
+	}
 
-		/* Setting up the global kconsumerd_pid */
-		kconsumerd_pid = ret;
+	ret = spawn_kconsumerd();
+	if (ret < 0) {
+		ERR("Spawning kconsumerd failed");
+		ret = LTTCOMM_KERN_CONSUMER_FAIL;
+		pthread_mutex_unlock(&kconsumerd_pid_mutex);
+		goto error;
 	}
+
+	/* Setting up the global kconsumerd_pid */
+	kconsumerd_pid = ret;
 	pthread_mutex_unlock(&kconsumerd_pid_mutex);
 
 	DBG("Kconsumerd pid %d", ret);
@@ -544,6 +546,8 @@ static int start_kconsumerd(void)
 		goto error;
 	}
 
+end:
+	pthread_mutex_unlock(&kconsumerd_pid_mutex);
 	return 0;
 
 error: