X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=libust%2Ftracectl.c;h=2f9215e65b29adc0df6095ce72c206425304c559;hb=6a843332a8ac7d1125e0961f148cc494e0397923;hp=7a5cf9562282ce7fe90cc3d5e4c405d3bf44b8c6;hpb=f51d84eac11907346fa02e33da358aad171ac80a;p=ust.git

diff --git a/libust/tracectl.c b/libust/tracectl.c
index 7a5cf95..2f9215e 100644
--- a/libust/tracectl.c
+++ b/libust/tracectl.c
@@ -15,6 +15,11 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
  */
 
+/* This file contains the implementation of the UST listener thread, which
+ * receives trace control commands. It also coordinates the initialization of
+ * libust.
+ */
+
 #define _GNU_SOURCE
 #include <stdio.h>
 #include <stdlib.h>
@@ -49,6 +54,8 @@
  */
 s64 pidunique = -1LL;
 
+extern struct chan_info_struct chan_infos[];
+
 struct list_head blocked_consumers = LIST_HEAD_INIT(blocked_consumers);
 
 static struct ustcomm_app ustcomm_app;
@@ -1114,6 +1121,11 @@ static void __attribute__((constructor)) init()
 {
 	int result;
 	char* autoprobe_val = NULL;
+	char* subbuffer_size_val = NULL;
+	char* subbuffer_count_val = NULL;
+	unsigned int subbuffer_size;
+	unsigned int subbuffer_count;
+	unsigned int power;
 
 	/* Assign the pidunique, to be able to differentiate the processes with same
 	 * pid, (before and after an exec).
@@ -1197,6 +1209,23 @@ static void __attribute__((constructor)) init()
 		}
 	}
 
+	subbuffer_size_val = getenv("UST_SUBBUF_SIZE");
+	if(subbuffer_size_val) {
+		sscanf(subbuffer_size_val, "%u", &subbuffer_size);
+		power = pow2_higher_or_eq(subbuffer_size);
+		if(power != subbuffer_size)
+			WARN("using the next power of two for buffer size = %u\n", power);
+		chan_infos[LTT_CHANNEL_UST].def_subbufsize = power;
+	}
+
+	subbuffer_count_val = getenv("UST_SUBBUF_NUM");
+	if(subbuffer_count_val) {
+		sscanf(subbuffer_count_val, "%u", &subbuffer_count);
+		if(subbuffer_count < 2)
+			subbuffer_count = 2;
+		chan_infos[LTT_CHANNEL_UST].def_subbufcount = subbuffer_count;
+	}
+
 	if(getenv("UST_TRACE")) {
 		char trace_name[] = "auto";
 		char trace_type[] = "ustrelay";
@@ -1263,7 +1292,6 @@ static void __attribute__((constructor)) init()
 		inform_consumer_daemon(trace_name);
 	}
 
-
 	return;
 
 	/* should decrementally destroy stuff if error */