[lttng-dev] [RFC PATCH 1/2] Add -ust to the name of UST threads of the application

[Raphaël Beamonte]

Add the required functions to change the thread name of the UST
threads and add the -ust string at its end. This will help to
identify LTTng-UST processes when analyzing the trace of a process.

Signed-off-by: Raphaël Beamonte <raphael.beamonte at gmail.com>
---
 liblttng-ust/compat.h         | 22 ++++++++++++++++++++++
 liblttng-ust/lttng-ust-comm.c |  2 ++
 2 files changed, 24 insertions(+)

diff --git a/liblttng-ust/compat.h b/liblttng-ust/compat.h
index 43b2223..8d5fc77 100644
--- a/liblttng-ust/compat.h
+++ b/liblttng-ust/compat.h
@@ -34,6 +34,23 @@ void lttng_ust_getprocname(char *name)
 	(void) prctl(PR_GET_NAME, (unsigned long) name, 0, 0, 0);
 }
 
+static inline
+void lttng_ust_setustprocname()
+{
+	char name[LTTNG_UST_PROCNAME_LEN];
+	int limit = LTTNG_UST_PROCNAME_LEN - 4;
+
+	lttng_ust_getprocname(name);
+
+	if (strlen(name) >= limit) {
+		name[limit] = 0;
+	}
+
+	sprintf(name, "%s%s", name, "-ust");
+
+	(void) prctl(PR_SET_NAME, name, 0, 0, 0);
+}
+
 #elif defined(__FreeBSD__)
 #include <stdlib.h>
 #include <string.h>
@@ -59,6 +76,11 @@ void lttng_ust_getprocname(char *name)
 		strncpy(name, bsd_name, LTTNG_UST_PROCNAME_LEN - 1);
 }
 
+static inline
+void lttng_ust_setustprocname()
+{
+}
+
 #endif
 
 #include <errno.h>
diff --git a/liblttng-ust/lttng-ust-comm.c b/liblttng-ust/lttng-ust-comm.c
index e00a22c..a85cb21 100644
--- a/liblttng-ust/lttng-ust-comm.c
+++ b/liblttng-ust/lttng-ust-comm.c
@@ -1295,6 +1295,8 @@ void *ust_listener_thread(void *arg)
 	int sock, ret, prev_connect_failed = 0, has_waited = 0;
 	long timeout;
 
+	lttng_ust_setustprocname();
+
 	/* Restart trying to connect to the session daemon */
 restart:
 	if (prev_connect_failed) {
-- 
2.1.4