Fix: sessiond: sessiond and agent deadlock on destroy

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

diff --git a/src/bin/lttng-sessiond/agent.c b/src/bin/lttng-sessiond/agent.c
index 1926b0820fc808f4076e12b8110a4ce5fe34cbae..e5978be5cef3ac24ecc7b7255cff563f87b13580 100644 (file)
--- a/src/bin/lttng-sessiond/agent.c
+++ b/src/bin/lttng-sessiond/agent.c
@@ -380,7 +380,7 @@ error:
  *
  * Return LTTNG_OK on success or else a LTTNG_ERR* code.
  */
-static int enable_event(struct agent_app *app, struct agent_event *event)
+static int enable_event(const struct agent_app *app, struct agent_event *event)
 {
        int ret;
        char *bytes_to_send;
@@ -495,8 +495,8 @@ end:
  *
  * Return LTTNG_OK on success or else a LTTNG_ERR* code.
  */
-static int app_context_op(struct agent_app *app,
-               struct agent_app_ctx *ctx, enum lttcomm_agent_command cmd)
+static int app_context_op(const struct agent_app *app,
+               const struct agent_app_ctx *ctx, enum lttcomm_agent_command cmd)
 {
        int ret;
        uint32_t reply_ret_code;
@@ -946,7 +946,7 @@ struct agent_app *agent_create_app(pid_t pid, enum lttng_domain_type domain,
 
        app = zmalloc(sizeof(*app));
        if (!app) {
-               PERROR("zmalloc agent create");
+               PERROR("Failed to allocate agent application instance");
                goto error;
        }
 
@@ -1402,26 +1402,24 @@ void agent_app_ht_clean(void)
  * Note that this function is most likely to be used with a tracing session
  * thus the caller should make sure to hold the appropriate lock(s).
  */
-void agent_update(struct agent *agt, int sock)
+void agent_update(const struct agent *agt, const struct agent_app *app)
 {
        int ret;
-       struct agent_app *app;
        struct agent_event *event;
        struct lttng_ht_iter iter;
        struct agent_app_ctx *ctx;
 
        assert(agt);
-       assert(sock >= 0);
+       assert(app);
 
-       DBG("Agent updating app socket %d", sock);
+       DBG("Agent updating app: pid = %ld", (long) app->pid);
 
        rcu_read_lock();
-       app = agent_find_app_by_sock(sock);
        /*
         * We are in the registration path thus if the application is gone,
         * there is a serious code flow error.
         */
-       assert(app);
+
        cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
                /* Skip event if disabled. */
                if (!event->enabled) {