Remove the sessiond "ready" counter mechanism

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

diff --git a/src/bin/lttng-sessiond/health.c b/src/bin/lttng-sessiond/health.c
index e2b8cc5a3e1b3794b75299737f064e9ac3fff220..e8c42e4bd7fa6f2b8b7394e9af43461be4b26fb4 100644 (file)
--- a/src/bin/lttng-sessiond/health.c
+++ b/src/bin/lttng-sessiond/health.c
@@ -27,17 +27,39 @@
 #include "utils.h"
 #include "thread.h"
 
-static void cleanup_health_management_thread(void *thread_data)
+struct thread_notifiers {
+       struct lttng_pipe *quit_pipe;
+       sem_t ready;
+};
+
+static
+void mark_thread_as_ready(struct thread_notifiers *notifiers)
 {
-       struct lttng_pipe *quit_pipe = thread_data;
+       DBG("Marking health management thread as ready");
+       sem_post(&notifiers->ready);
+}
 
-       lttng_pipe_destroy(quit_pipe);
+static
+void wait_until_thread_is_ready(struct thread_notifiers *notifiers)
+{
+       DBG("Waiting for health management thread to be ready");
+       sem_wait(&notifiers->ready);
+       DBG("Health management thread is ready");
+}
+
+static void cleanup_health_management_thread(void *data)
+{
+       struct thread_notifiers *notifiers = data;
+
+       lttng_pipe_destroy(notifiers->quit_pipe);
+       sem_destroy(&notifiers->ready);
+       free(notifiers);
 }
 
 /*
  * Thread managing health check socket.
  */
-static void *thread_manage_health(void *thread_data)
+static void *thread_manage_health(void *data)
 {
        const bool is_root = (getuid() == 0);
        int sock = -1, new_sock = -1, ret, i, pollfd, err = -1;
@@ -46,8 +68,9 @@ static void *thread_manage_health(void *thread_data)
        struct health_comm_msg msg;
        struct health_comm_reply reply;
        /* Thread-specific quit pipe. */
-       struct lttng_pipe *quit_pipe = thread_data;
-       const int quit_pipe_read_fd = lttng_pipe_get_readfd(quit_pipe);
+       struct thread_notifiers *notifiers = data;
+       const int quit_pipe_read_fd = lttng_pipe_get_readfd(
+                       notifiers->quit_pipe);
 
        DBG("[thread] Manage health check started");
 
@@ -111,8 +134,7 @@ static void *thread_manage_health(void *thread_data)
                goto error;
        }
 
-       sessiond_notify_ready();
-
+       mark_thread_as_ready(notifiers);
        while (1) {
                DBG("Health check ready");
 
@@ -228,44 +250,42 @@ error:
        return NULL;
 }
 
-static bool shutdown_health_management_thread(void *thread_data)
+static bool shutdown_health_management_thread(void *data)
 {
-       int ret;
-       int pipe_write_fd;
-       struct lttng_pipe *health_quit_pipe = thread_data;
+       struct thread_notifiers *notifiers = data;
+       const int write_fd = lttng_pipe_get_writefd(notifiers->quit_pipe);
 
-       pipe_write_fd = lttng_pipe_get_writefd(health_quit_pipe);
-       ret = notify_thread_pipe(pipe_write_fd);
-       if (ret < 0) {
-               ERR("Failed to notify Health management thread's quit pipe");
-               goto error;
-       }
-       return true;
-error:
-       return false;
+       return notify_thread_pipe(write_fd) == 1;
 }
 
 bool launch_health_management_thread(void)
 {
+       struct thread_notifiers *notifiers;
        struct lttng_thread *thread;
-       struct lttng_pipe *health_quit_pipe = NULL;
 
-       health_quit_pipe = lttng_pipe_open(FD_CLOEXEC);
-       if (!health_quit_pipe) {
+       notifiers = zmalloc(sizeof(*notifiers));
+       if (!notifiers) {
                goto error;
        }
 
+       sem_init(&notifiers->ready, 0, 0);
+       notifiers->quit_pipe = lttng_pipe_open(FD_CLOEXEC);
+       if (!notifiers->quit_pipe) {
+               goto error;
+       }
        thread = lttng_thread_create("Health management",
                        thread_manage_health,
                        shutdown_health_management_thread,
                        cleanup_health_management_thread,
-                       health_quit_pipe);
+                       notifiers);
        if (!thread) {
                goto error;
        }
+
+       wait_until_thread_is_ready(notifiers);
        lttng_thread_put(thread);
        return true;
 error:
-       cleanup_health_management_thread(health_quit_pipe);
+       cleanup_health_management_thread(notifiers);
        return false;
 }