diff options
| -rw-r--r-- | include/private/pthread_stop_world.h | 5 | ||||
| -rw-r--r-- | pthread_stop_world.c | 15 | ||||
| -rw-r--r-- | pthread_support.c | 26 |
3 files changed, 38 insertions, 8 deletions
diff --git a/include/private/pthread_stop_world.h b/include/private/pthread_stop_world.h index a1b52da7..81581dd4 100644 --- a/include/private/pthread_stop_world.h +++ b/include/private/pthread_stop_world.h @@ -54,6 +54,11 @@ GC_INNER void GC_stop_init(void); GC_INNER void *GC_CALLBACK suspend_self_inner(void *client_data); #endif +#if defined(CAN_HANDLE_FORK) && defined(THREAD_SANITIZER) \ + && defined(SIGNAL_BASED_STOP_WORLD) + GC_EXTERN GC_bool GC_retry_signals; +#endif + EXTERN_C_END #endif diff --git a/pthread_stop_world.c b/pthread_stop_world.c index ba0771c9..cbb3b2b8 100644 --- a/pthread_stop_world.c +++ b/pthread_stop_world.c @@ -142,13 +142,12 @@ STATIC volatile AO_t GC_stop_count; /* before they are expected to stop (unless */ /* they have stopped voluntarily). */ -#ifndef NO_RETRY_SIGNALS - /* Any platform could lose signals, so let's be conservative and */ - /* always enable signals retry logic. */ - STATIC GC_bool GC_retry_signals = TRUE; +#if defined(CAN_HANDLE_FORK) && defined(THREAD_SANITIZER) + GC_INNER #else - STATIC GC_bool GC_retry_signals = FALSE; + STATIC #endif + GC_bool GC_retry_signals = FALSE; /* * We use signals to stop threads during GC. @@ -1404,6 +1403,11 @@ GC_INNER void GC_stop_init(void) if (sigdelset(&suspend_handler_mask, GC_sig_thr_restart) != 0) ABORT("sigdelset failed"); +# ifndef NO_RETRY_SIGNALS + /* Any platform could lose signals, so let's be conservative and */ + /* always enable signals retry logic. */ + GC_retry_signals = TRUE; +# endif /* Override the default value of GC_retry_signals. */ str = GETENV("GC_RETRY_SIGNALS"); if (str != NULL) { @@ -1418,6 +1422,7 @@ GC_INNER void GC_stop_init(void) GC_COND_LOG_PRINTF( "Will retry suspend and restart signals if necessary\n"); } + # ifndef NO_SIGNALS_UNBLOCK_IN_MAIN /* Explicitly unblock the signals once before new threads creation. */ GC_unblock_gc_signals(); diff --git a/pthread_support.c b/pthread_support.c index 6742b1d8..1cc76b57 100644 --- a/pthread_support.c +++ b/pthread_support.c @@ -820,10 +820,12 @@ GC_API void GC_CALL GC_register_altstack(void *stack, GC_word stack_size, /* Remove all entries from the GC_threads table, except the */ /* one for the current thread. We need to do this in the child */ /* process after a fork(), since only the current thread */ -/* survives in the child. */ -STATIC void GC_remove_all_threads_but_me(void) +/* survives in the child. Returns true if at least one thread */ +/* has been removed. */ +STATIC GC_bool GC_remove_all_threads_but_me(void) { pthread_t self = pthread_self(); + GC_bool removed = FALSE; int hv; for (hv = 0; hv < THREAD_TABLE_SZ; ++hv) { @@ -875,10 +877,12 @@ STATIC void GC_remove_all_threads_but_me(void) # if !defined(THREAD_SANITIZER) || !defined(CAN_CALL_ATFORK) if (p != &first_thread) GC_INTERNAL_FREE(p); # endif + removed = TRUE; } } store_to_threads_table(hv, me); } + return removed; } #endif /* CAN_HANDLE_FORK */ @@ -1226,6 +1230,8 @@ static void fork_parent_proc(void) #endif static void fork_child_proc(void) { + GC_bool threads_removed; + GC_release_dirty_lock(); # if defined(PARALLEL_MARK) if (GC_parallel) { @@ -1238,7 +1244,21 @@ static void fork_child_proc(void) } # endif /* Clean up the thread table, so that just our thread is left. */ - GC_remove_all_threads_but_me(); + threads_removed = GC_remove_all_threads_but_me(); +# if defined(THREAD_SANITIZER) && defined(SIGNAL_BASED_STOP_WORLD) + /* If a multi-threaded process has been forked, then TSan (as of */ + /* now) cannot reasonably function in the child, e.g. usleep() */ + /* may hang because some internal lock is not released at fork. */ + if (threads_removed +# ifdef PARALLEL_MARK + || GC_parallel +# endif + ) { + GC_retry_signals = FALSE; + } +# else + (void)threads_removed; +# endif # ifdef PARALLEL_MARK /* Turn off parallel marking in the child, since we are probably */ /* just going to exec, and we would have to restart mark threads. */ |