Introduce SgenObjectOperations that holds all copy/scan functions needed by a given...

[mono.git] / mono / metadata / sgen-os-posix.c

diff --git a/mono/metadata/sgen-os-posix.c b/mono/metadata/sgen-os-posix.c
index 49b7deff50cae62a57876855930d2e8e05cde1ba..276923779f9e9b5b7034ab00f9936d860e96f0d8 100644 (file)
--- a/mono/metadata/sgen-os-posix.c
+++ b/mono/metadata/sgen-os-posix.c
@@ -51,6 +51,7 @@ static MonoSemType suspend_ack_semaphore;
 static MonoSemType *suspend_ack_semaphore_ptr;
 
 static sigset_t suspend_signal_mask;
+static sigset_t suspend_ack_signal_mask;
 
 static void
 suspend_thread (SgenThreadInfo *info, void *context)
@@ -67,12 +68,12 @@ suspend_thread (SgenThreadInfo *info, void *context)
 
        info->stopped_domain = mono_domain_get ();
        info->stopped_ip = context ? (gpointer) ARCH_SIGCTX_IP (context) : NULL;
-       stop_count = mono_sgen_global_stop_count;
+       stop_count = sgen_global_stop_count;
        /* duplicate signal */
        if (0 && info->stop_count == stop_count)
                return;
 
-       mono_sgen_fill_thread_info_for_suspend (info);
+       sgen_fill_thread_info_for_suspend (info);
 
        stack_start = context ? (char*) ARCH_SIGCTX_SP (context) - REDZONE_SIZE : NULL;
        /* If stack_start is not within the limits, then don't set it
@@ -104,6 +105,14 @@ suspend_thread (SgenThreadInfo *info, void *context)
                mono_gc_get_gc_callbacks ()->thread_suspend_func (info->runtime_data, context);
 
        DEBUG (4, fprintf (gc_debug_file, "Posting suspend_ack_semaphore for suspend from %p %p\n", info, (gpointer)mono_native_thread_id_get ()));
+
+       /*
+       Block the restart signal. 
+       We need to block the restart signal while posting to the suspend_ack semaphore or we race to sigsuspend,
+       which might miss the signal and get stuck.
+       */
+       pthread_sigmask (SIG_BLOCK, &suspend_ack_signal_mask, NULL);
+
        /* notify the waiting thread */
        MONO_SEM_POST (suspend_ack_semaphore_ptr);
        info->stop_count = stop_count;
@@ -114,6 +123,9 @@ suspend_thread (SgenThreadInfo *info, void *context)
                sigsuspend (&suspend_signal_mask);
        } while (info->signal != restart_signal_num && info->doing_handshake);
 
+       /* Unblock the restart signal. */
+       pthread_sigmask (SIG_UNBLOCK, &suspend_ack_signal_mask, NULL);
+
        DEBUG (4, fprintf (gc_debug_file, "Posting suspend_ack_semaphore for resume from %p %p\n", info, (gpointer)mono_native_thread_id_get ()));
        /* notify the waiting thread */
        MONO_SEM_POST (suspend_ack_semaphore_ptr);
@@ -145,6 +157,15 @@ restart_handler (int sig)
        int old_errno = errno;
 
        info = mono_thread_info_current ();
+       /*
+       If the thread info is null is means we're currently in the process of cleaning up,
+       the pthread destructor has already kicked in and it has explicitly invoked the suspend handler.
+       
+       This means this thread has been suspended, TLS is dead, so the only option we have is to
+       rely on pthread_self () and seatch over the thread list.
+       */
+       if (!info)
+               info = mono_thread_info_lookup (pthread_self ());
 
        /*
         * If a thread is dying there might be no thread info.  In
@@ -154,24 +175,23 @@ restart_handler (int sig)
                info->signal = restart_signal_num;
                DEBUG (4, fprintf (gc_debug_file, "Restart handler in %p %p\n", info, (gpointer)mono_native_thread_id_get ()));
        }
-
        errno = old_errno;
 }
 
 gboolean
-mono_sgen_resume_thread (SgenThreadInfo *info)
+sgen_resume_thread (SgenThreadInfo *info)
 {
        return mono_threads_pthread_kill (info, restart_signal_num) == 0;
 }
 
 gboolean
-mono_sgen_suspend_thread (SgenThreadInfo *info)
+sgen_suspend_thread (SgenThreadInfo *info)
 {
        return mono_threads_pthread_kill (info, suspend_signal_num) == 0;
 }
 
 void
-mono_sgen_wait_for_suspend_ack (int count)
+sgen_wait_for_suspend_ack (int count)
 {
        int i, result;
 
@@ -185,7 +205,7 @@ mono_sgen_wait_for_suspend_ack (int count)
 }
 
 gboolean
-mono_sgen_park_current_thread_if_doing_handshake (SgenThreadInfo *p)
+sgen_park_current_thread_if_doing_handshake (SgenThreadInfo *p)
 {
     if (!p->doing_handshake)
            return FALSE;
@@ -195,7 +215,7 @@ mono_sgen_park_current_thread_if_doing_handshake (SgenThreadInfo *p)
 }
 
 int
-mono_sgen_thread_handshake (BOOL suspend)
+sgen_thread_handshake (BOOL suspend)
 {
        int count, result;
        SgenThreadInfo *info;
@@ -208,6 +228,8 @@ mono_sgen_thread_handshake (BOOL suspend)
                if (mono_native_thread_id_equals (mono_thread_info_get_tid (info), me)) {
                        continue;
                }
+               if (info->gc_disabled)
+                       continue;
                /*if (signum == suspend_signal_num && info->stop_count == global_stop_count)
                        continue;*/
                if (suspend) {
@@ -225,13 +247,13 @@ mono_sgen_thread_handshake (BOOL suspend)
                }
        } END_FOREACH_THREAD_SAFE
 
-       mono_sgen_wait_for_suspend_ack (count);
+       sgen_wait_for_suspend_ack (count);
 
        return count;
 }
 
 void
-mono_sgen_os_init (void)
+sgen_os_init (void)
 {
        struct sigaction sinfo;
 
@@ -252,6 +274,10 @@ mono_sgen_os_init (void)
 
        sigfillset (&suspend_signal_mask);
        sigdelset (&suspend_signal_mask, restart_signal_num);
+
+       sigemptyset (&suspend_ack_signal_mask);
+       sigaddset (&suspend_ack_signal_mask, restart_signal_num);
+       
 }
 
 int