Fix out-of-band deref of (potentially) gone threads structure

[fio.git] / fio.c

diff --git a/fio.c b/fio.c
index c79fad87600d53f4565bcb96c442938883fc5327..37a425e85ee6fde71ec7aa537b0f6947687cc128 100644 (file)
--- a/fio.c
+++ b/fio.c
@@ -101,6 +101,9 @@ static void terminate_threads(int group_id)
 
 static void sig_handler(int sig)
 {
+       if (!threads)
+               return;
+
        switch (sig) {
        case SIGALRM:
                update_io_ticks();
@@ -412,10 +415,10 @@ sync_done:
                 */
                min_events = 0;
                if (queue_full(td) || ret == FIO_Q_BUSY) {
-                       min_events = 1;
-
-                       if (td->cur_depth > td->o.iodepth_low)
+                       if (td->cur_depth >= td->o.iodepth_low)
                                min_events = td->cur_depth - td->o.iodepth_low;
+                       if (!min_events)
+                               min_events = 1;
                }
 
                /*
@@ -545,16 +548,12 @@ sync_done:
                /*
                 * See if we need to complete some commands
                 */
-               if (ret == FIO_Q_QUEUED || ret == FIO_Q_BUSY) {
+               if (queue_full(td) || ret == FIO_Q_BUSY) {
                        min_evts = 0;
-                       if (queue_full(td) || ret == FIO_Q_BUSY) {
+                       if (td->cur_depth >= td->o.iodepth_low)
+                               min_evts = td->cur_depth - td->o.iodepth_low;
+                       if (!min_evts)
                                min_evts = 1;
-
-                               if (td->cur_depth > td->o.iodepth_low)
-                                       min_evts = td->cur_depth
-                                                       - td->o.iodepth_low;
-                       }
-
                        fio_gettime(&comp_time, NULL);
                        bytes_done = io_u_queued_complete(td, min_evts);
                        if (bytes_done < 0)
@@ -1237,12 +1236,15 @@ static void run_threads(void)
                                if (pthread_detach(td->thread) < 0)
                                        perror("pthread_detach");
                        } else {
+                               pid_t pid;
                                dprint(FD_PROCESS, "will fork\n");
-                               if (!fork()) {
+                               pid = fork();
+                               if (!pid) {
                                        int ret = fork_main(shm_id, i);
 
-                                       exit(ret);
-                               }
+                                       _exit(ret);
+                               } else if (i == fio_debug_jobno)
+                                       *fio_debug_jobp = pid;
                        }
                        fio_mutex_down(startup_mutex);
                }