fix some possible hangs in threaded loops

hopefully helps #32258
JuliaLang · Jun 19, 2019 · 685a9e3 · 685a9e3
1 parent 5579bc6
commit 685a9e3
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Showing 2 changed files with 11 additions and 7 deletions.
diff --git a/src/jl_uv.c b/src/jl_uv.c
@@ -190,6 +190,8 @@ JL_DLLEXPORT void jl_uv_req_set_data(uv_req_t *req, void *data) { req->data = da
 JL_DLLEXPORT void *jl_uv_handle_data(uv_handle_t *handle) { return handle->data; }
 JL_DLLEXPORT void *jl_uv_write_handle(uv_write_t *req) { return req->handle; }
 
+extern volatile unsigned _threadedregion;
+
 JL_DLLEXPORT int jl_run_once(uv_loop_t *loop)
 {
     jl_ptls_t ptls = jl_get_ptls_states();
@@ -207,13 +209,14 @@ JL_DLLEXPORT int jl_run_once(uv_loop_t *loop)
 JL_DLLEXPORT int jl_process_events(uv_loop_t *loop)
 {
     jl_ptls_t ptls = jl_get_ptls_states();
-    if (loop) {
+    if (loop && (_threadedregion || ptls->tid == 0)) {
         jl_gc_safepoint_(ptls);
-        JL_UV_LOCK();
-        loop->stop_flag = 0;
-        int r = uv_run(loop,UV_RUN_NOWAIT);
-        JL_UV_UNLOCK();
-        return r;
+        if (jl_mutex_trylock(&jl_uv_mutex)) {
+            loop->stop_flag = 0;
+            int r = uv_run(loop,UV_RUN_NOWAIT);
+            JL_UV_UNLOCK();
+            return r;
+        }
     }
     return 0;
 }

diff --git a/src/partr.c b/src/partr.c
@@ -254,10 +254,12 @@ JL_DLLEXPORT void jl_wakeup_thread(int16_t tid)
 // get the next runnable task from the multiq
 static jl_task_t *get_next_task(jl_value_t *getsticky)
 {
+    jl_gc_safepoint();
     jl_task_t *task = (jl_task_t*)jl_apply(&getsticky, 1);
     if (jl_typeis(task, jl_task_type))
         return task;
 #ifdef JULIA_ENABLE_THREADING
+    jl_gc_safepoint();
     return multiq_deletemin();
 #else
     return NULL;
@@ -273,7 +275,6 @@ JL_DLLEXPORT jl_task_t *jl_task_get_next(jl_value_t *getsticky)
     jl_task_t *task;
 
     while (1) {
-        jl_gc_safepoint();
         task = get_next_task(getsticky);
         if (task)
             return task;