[runtime] Defer async requests during abort protected blocks

We avoid unnecessary checks for each interruption checkpoint.

diff --git a/mono/metadata/threads.c b/mono/metadata/threads.c
index a92dc12f3492f3b7b8121de16b9a5770ddeb436b..86c6b8173ea3d49e8b709c557cc835f613784a68 100644 (file)
--- a/mono/metadata/threads.c
+++ b/mono/metadata/threads.c
@@ -259,6 +259,10 @@ mono_threads_begin_abort_protected_block (void)
 
                new_state = old_state + (1 << ABORT_PROT_BLOCK_SHIFT);
        } while (InterlockedCompareExchangePointer ((volatile gpointer)&thread->thread_state, (gpointer)new_state, (gpointer)old_state) != (gpointer)old_state);
+
+       /* Defer async request since we won't be able to process until exiting the block */
+       if (new_val == 1 && (new_state & INTERRUPT_ASYNC_REQUESTED_BIT))
+               InterlockedDecrement (&thread_interruption_requested);
 }
 
 static gboolean
@@ -280,17 +284,21 @@ mono_threads_end_abort_protected_block (void)
 {
        MonoInternalThread *thread = mono_thread_internal_current ();
        gsize old_state, new_state;
+       int new_val;
        do {
                old_state = thread->thread_state;
 
                //bounds check abort_prot_count
-               int new_val = ((old_state & ABORT_PROT_BLOCK_MASK) >> ABORT_PROT_BLOCK_SHIFT) - 1;
+               new_val = ((old_state & ABORT_PROT_BLOCK_MASK) >> ABORT_PROT_BLOCK_SHIFT) - 1;
                g_assert (new_val >= 0);
                g_assert (new_val < (1 << ABORT_PROT_BLOCK_BITS));
 
                new_state = old_state - (1 << ABORT_PROT_BLOCK_SHIFT);
        } while (InterlockedCompareExchangePointer ((volatile gpointer)&thread->thread_state, (gpointer)new_state, (gpointer)old_state) != (gpointer)old_state);
 
+       if (new_val == 0 && (new_state & INTERRUPT_ASYNC_REQUESTED_BIT))
+               InterlockedIncrement (&thread_interruption_requested);
+
        return mono_thread_state_has_interruption (new_state);
 }
 
@@ -350,7 +358,8 @@ mono_thread_set_interruption_requested (MonoInternalThread *thread)
                        new_state = old_state | INTERRUPT_ASYNC_REQUESTED_BIT;
        } while (InterlockedCompareExchangePointer ((volatile gpointer)&thread->thread_state, (gpointer)new_state, (gpointer)old_state) != (gpointer)old_state);
 
-       InterlockedIncrement (&thread_interruption_requested);
+       if (sync || !(new_state & ABORT_PROT_BLOCK_MASK))
+               InterlockedIncrement (&thread_interruption_requested);
 
        return sync || !(new_state & ABORT_PROT_BLOCK_MASK);
 }