repair sigtimedwait profiling

also fix race cond. in thread init (_julia_init could read thread state before it was setup)
JuliaLang · Sep 18, 2015 · a38fee2 · a38fee2
1 parent 4971105
commit a38fee2
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Showing 2 changed files with 22 additions and 8 deletions.
diff --git a/src/signals-unix.c b/src/signals-unix.c
@@ -186,14 +186,20 @@ void usr2_handler(int sig, siginfo_t *info, void *ctx)
     }
 }
 
-#if defined(HAVE_TIMEDSIGWAIT)
+#if defined(HAVE_SIGTIMEDWAIT)
 
 static struct timespec timeoutprof;
 DLLEXPORT int jl_profile_start_timer(void)
 {
     timeoutprof.tv_sec = nsecprof/GIGA;
     timeoutprof.tv_nsec = nsecprof%GIGA;
     pthread_kill(signals_thread, SIGUSR2); // notify signal handler to start timer
+    return 0;
+}
+
+DLLEXPORT void jl_profile_stop_timer(void)
+{
+    pthread_kill(signals_thread, SIGUSR2);
 }
 
 #elif defined(HAVE_TIMER)
@@ -325,14 +331,14 @@ static void *signal_listener(void *arg)
     int sig, critical, profile;
     int i;
     jl_sigsetset(&sset);
-#if defined(HAVE_TIMEDSIGWAIT)
-    siginfo_t *info;
-    sigaddset(sset, SIGUSR2);
+#ifdef HAVE_SIGTIMEDWAIT
+    siginfo_t info;
+    sigaddset(&sset, SIGUSR2);
     sigprocmask(SIG_SETMASK, &sset, 0);
 #endif
     while (1) {
         profile = 0;
-#if HAVE_TIMEDSIGWAIT
+#ifdef HAVE_SIGTIMEDWAIT
         if (running) {
             sig = sigtimedwait(&sset, &info, &timeoutprof);
         }
@@ -343,15 +349,16 @@ static void *signal_listener(void *arg)
             int err = errno;
             if (err == EAGAIN) {
                 // this was a timeout event
-                profile = true;
+                profile = 1;
             }
             else {
                 assert(err == EINTR);
                 continue;
             }
         }
         else if (sig == SIGUSR2) {
-            // notification to start profiler
+            // notification to toggle profiler
+            running = !running;
             continue;
         }
 #else

diff --git a/src/threading.c b/src/threading.c
@@ -158,6 +158,8 @@ static jl_value_t *ti_run_fun(jl_function_t *f, jl_svec_t *args)
     return jl_nothing;
 }
 
+static uv_barrier_t thread_init_done;
+
 // thread function: used by all except the main thread
 void ti_threadfun(void *arg)
 {
@@ -177,7 +179,7 @@ void ti_threadfun(void *arg)
     while (ta->state == TI_THREAD_INIT)
         cpu_pause();
     cpu_lfence();
-
+    uv_barrier_wait(&thread_init_done);
     // initialize this thread in the thread group
     tg = ta->tg;
     ti_threadgroup_initthread(tg, ti_tid);
@@ -295,6 +297,9 @@ void jl_start_threads(void)
     jl_all_task_states[0].system_id = pthread_self();
 #endif
     targs = malloc((jl_n_threads - 1) * sizeof (ti_threadarg_t *));
+
+    uv_barrier_init(&thread_init_done, jl_n_threads);
+
     for (i = 0;  i < jl_n_threads - 1;  ++i) {
         targs[i] = (ti_threadarg_t *)malloc(sizeof (ti_threadarg_t));
         targs[i]->state = TI_THREAD_INIT;
@@ -316,6 +321,8 @@ void jl_start_threads(void)
         targs[i]->state = TI_THREAD_WORK;
     }
 
+    uv_barrier_wait(&thread_init_done);
+
     // free the argument array; the threads will free their arguments
     free(targs);
 }