[sgen] Make sure we don't sweep a block if we're not supposed to

If the sweeping mechanism has been triggered by a major collection, then the iteration will wait for the general sweeping to finish and also for the sweeping of all the blocks. If this isn't the case (we are doing a major collection) we will iterate over the current state of the heap, some objects being bound to die during the collection, and the callback must account for this.

It doesn't make much sense to explicitly attempt to iterate without trying to sweep blocks that can be swept.

diff --git a/mono/sgen/sgen-debug.c b/mono/sgen/sgen-debug.c
index 43237fdfacbaf75b80c52f1d6bb1264ca0943128..cb2fbb7f7c68b8eaab143ff3701dc912bc5f509b 100644 (file)
--- a/mono/sgen/sgen-debug.c
+++ b/mono/sgen/sgen-debug.c
@@ -251,7 +251,7 @@ sgen_check_mod_union_consistency (void)
 {
        missing_remsets = FALSE;
 
-       major_collector.iterate_objects (ITERATE_OBJECTS_ALL, (IterateObjectCallbackFunc)check_mod_union_callback, (void*)FALSE);
+       major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_ALL, (IterateObjectCallbackFunc)check_mod_union_callback, (void*)FALSE);
 
        sgen_los_iterate_objects ((IterateObjectCallbackFunc)check_mod_union_callback, (void*)TRUE);
 

diff --git a/mono/sgen/sgen-gc.h b/mono/sgen/sgen-gc.h
index f67a15cd74aac377e7eded4aecf705bf60fcd789..dd5aef0392704810a21de0e4fe2de949104e2268 100644 (file)
--- a/mono/sgen/sgen-gc.h
+++ b/mono/sgen/sgen-gc.h
@@ -599,7 +599,6 @@ typedef enum {
        ITERATE_OBJECTS_SWEEP = 1,
        ITERATE_OBJECTS_NON_PINNED = 2,
        ITERATE_OBJECTS_PINNED = 4,
-       ITERATE_OBJECTS_ALL = ITERATE_OBJECTS_NON_PINNED | ITERATE_OBJECTS_PINNED,
        ITERATE_OBJECTS_SWEEP_NON_PINNED = ITERATE_OBJECTS_SWEEP | ITERATE_OBJECTS_NON_PINNED,
        ITERATE_OBJECTS_SWEEP_PINNED = ITERATE_OBJECTS_SWEEP | ITERATE_OBJECTS_PINNED,
        ITERATE_OBJECTS_SWEEP_ALL = ITERATE_OBJECTS_SWEEP | ITERATE_OBJECTS_NON_PINNED | ITERATE_OBJECTS_PINNED

diff --git a/mono/sgen/sgen-marksweep.c b/mono/sgen/sgen-marksweep.c
index bf3b5fad7eabc1e0bf1ff63a8b9b3e4b8ae8bf26..d29b91d37015dfbdf727caff0bed4016d99d3843 100644 (file)
--- a/mono/sgen/sgen-marksweep.c
+++ b/mono/sgen/sgen-marksweep.c
@@ -872,6 +872,7 @@ major_iterate_objects (IterateObjectsFlags flags, IterateObjectCallbackFunc call
        gboolean pinned = flags & ITERATE_OBJECTS_PINNED;
        MSBlockInfo *block;
 
+       /* No actual sweeping will take place if we are in the middle of a major collection. */
        major_finish_sweep_checking ();
        FOREACH_BLOCK_NO_LOCK (block) {
                int count = MS_BLOCK_FREE / block->obj_size;
@@ -881,7 +882,7 @@ major_iterate_objects (IterateObjectsFlags flags, IterateObjectCallbackFunc call
                        continue;
                if (!block->pinned && !non_pinned)
                        continue;
-               if (sweep && lazy_sweep) {
+               if (sweep && lazy_sweep && !block_is_swept_or_marking (block)) {
                        sweep_block (block);
                        SGEN_ASSERT (6, block->state == BLOCK_STATE_SWEPT, "Block must be swept after sweeping");
                }