Fix: add missing rcu_barrier before daemon teardown

[lttng-tools.git] / src / bin / lttng-consumerd / lttng-consumerd.c

diff --git a/src/bin/lttng-consumerd/lttng-consumerd.c b/src/bin/lttng-consumerd/lttng-consumerd.c
index 764cf4cb0f59ff981629c99078b31676d0f700b2..293654053e87ad046d4cc2716de75e1934b513f8 100644 (file)
--- a/src/bin/lttng-consumerd/lttng-consumerd.c
+++ b/src/bin/lttng-consumerd/lttng-consumerd.c
@@ -16,7 +16,6 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
-#define _GNU_SOURCE
 #define _LGPL_SOURCE
 #include <fcntl.h>
 #include <getopt.h>
@@ -38,14 +37,13 @@
 #include <unistd.h>
 #include <sys/mman.h>
 #include <assert.h>
-#include <config.h>
 #include <urcu/compiler.h>
 #include <ulimit.h>
 
 #include <common/defaults.h>
 #include <common/common.h>
-#include <common/consumer.h>
-#include <common/consumer-timer.h>
+#include <common/consumer/consumer.h>
+#include <common/consumer/consumer-timer.h>
 #include <common/compat/poll.h>
 #include <common/compat/getenv.h>
 #include <common/sessiond-comm/sessiond-comm.h>
@@ -101,15 +99,9 @@ static void sighandler(int sig)
                return;
        }
 
-       /*
-        * Ignore SIGPIPE because it should not stop the consumer whenever a
-        * SIGPIPE is catched through a FD operation.
-        */
-       if (sig == SIGPIPE) {
-               return;
+       if (ctx) {
+               lttng_consumer_should_exit(ctx);
        }
-
-       lttng_consumer_should_exit(ctx);
 }
 
 /*
@@ -127,9 +119,10 @@ static int set_signal_handler(void)
                return ret;
        }
 
-       sa.sa_handler = sighandler;
        sa.sa_mask = sigset;
        sa.sa_flags = 0;
+
+       sa.sa_handler = sighandler;
        if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
                PERROR("sigaction");
                return ret;
@@ -140,6 +133,7 @@ static int set_signal_handler(void)
                return ret;
        }
 
+       sa.sa_handler = SIG_IGN;
        if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
                PERROR("sigaction");
                return ret;
@@ -312,6 +306,7 @@ int main(int argc, char **argv)
 {
        int ret = 0, retval = 0;
        void *status;
+       struct lttng_consumer_local_data *tmp_ctx;
 
        if (set_signal_handler()) {
                retval = -1;
@@ -419,6 +414,10 @@ int main(int argc, char **argv)
                set_ulimit();
        }
 
+       if (run_as_create_worker(argv[0]) < 0) {
+               goto exit_init_data;
+       }
+
        /* create the consumer instance with and assign the callbacks */
        ctx = lttng_consumer_create(opt_type, lttng_consumer_read_subbuffer,
                NULL, lttng_consumer_on_recv_stream, NULL);
@@ -626,19 +625,29 @@ exit_health_thread:
 exit_health_pipe:
 
 exit_init_data:
-       lttng_consumer_destroy(ctx);
+       tmp_ctx = ctx;
+       ctx = NULL;
+       cmm_barrier();  /* Clear ctx for signal handler. */
+       /*
+        * Wait for all pending call_rcu work to complete before tearing
+        * down data structures. call_rcu worker may be trying to
+        * perform lookups in those structures.
+        */
+       rcu_barrier();
+       lttng_consumer_destroy(tmp_ctx);
        lttng_consumer_cleanup();
 
        if (health_consumerd) {
                health_app_destroy(health_consumerd);
        }
-exit_health_consumerd_cleanup:
+       /* Ensure all prior call_rcu are done. */
+       rcu_barrier();
 
-exit_options:
+       run_as_destroy_worker();
 
+exit_health_consumerd_cleanup:
+exit_options:
 exit_set_signal_handler:
-       /* Ensure all prior call_rcu are done. */
-       rcu_barrier();
 
        if (!retval) {
                exit(EXIT_SUCCESS);