Implement UST PID tracker

[lttng-tools.git] / src / bin / lttng-sessiond / main.c

diff --git a/src/bin/lttng-sessiond/main.c b/src/bin/lttng-sessiond/main.c
index f8f2a7ce3c1624923f8af606b620fe8f5f443fe3..966f609177ad0b28104de59f827ec73f7101de24 100644 (file)
--- a/src/bin/lttng-sessiond/main.c
+++ b/src/bin/lttng-sessiond/main.c
@@ -994,10 +994,30 @@ static void update_ust_app(int app_sock)
 
        /* For all tracing session(s) */
        cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
+               struct ust_app *app;
+
                session_lock(sess);
-               if (sess->ust_session) {
-                       ust_app_global_update(sess->ust_session, app_sock);
+               if (!sess->ust_session) {
+                       goto unlock_session;
                }
+
+               rcu_read_lock();
+               assert(app_sock >= 0);
+               app = ust_app_find_by_sock(app_sock);
+               if (app == NULL) {
+                       /*
+                        * Application can be unregistered before so
+                        * this is possible hence simply stopping the
+                        * update.
+                        */
+                       DBG3("UST app update failed to find app sock %d",
+                               app_sock);
+                       goto unlock_rcu;
+               }
+               ust_app_global_update(sess->ust_session, app);
+       unlock_rcu:
+               rcu_read_unlock();
+       unlock_session:
                session_unlock(sess);
        }
 }
@@ -3252,6 +3272,20 @@ skip_domain:
                                &cmd_ctx->lsm->u.channel.chan, kernel_poll_pipe[1]);
                break;
        }
+       case LTTNG_TRACK_PID:
+       {
+               ret = cmd_track_pid(cmd_ctx->session,
+                               cmd_ctx->lsm->domain.type,
+                               cmd_ctx->lsm->u.pid_tracker.pid);
+               break;
+       }
+       case LTTNG_UNTRACK_PID:
+       {
+               ret = cmd_untrack_pid(cmd_ctx->session,
+                               cmd_ctx->lsm->domain.type,
+                               cmd_ctx->lsm->u.pid_tracker.pid);
+               break;
+       }
        case LTTNG_ENABLE_EVENT:
        {
                struct lttng_event_exclusion *exclusion = NULL;
@@ -4612,6 +4646,10 @@ static int set_option(int opt, const char *arg, const char *optname)
                } else {
                        unsigned long v;
 
+                       if (!arg) {
+                               ret = -EINVAL;
+                               goto end;
+                       }
                        errno = 0;
                        v = strtoul(arg, NULL, 0);
                        if (errno != 0 || !isdigit(arg[0])) {