SWEEP_STATE_COMPACTING
};
+typedef enum {
+ SGEN_SWEEP_SERIAL = FALSE,
+ SGEN_SWEEP_CONCURRENT = TRUE,
+} SgenSweepMode;
+
static volatile int sweep_state = SWEEP_STATE_SWEPT;
static gboolean concurrent_mark;
-static gboolean concurrent_sweep = TRUE;
+static gboolean concurrent_sweep = DEFAULT_SWEEP_MODE;
int sweep_pool_context = -1;
/* non-allocated block free-list */
static void *empty_blocks = NULL;
static size_t num_empty_blocks = 0;
+static gboolean compact_blocks = FALSE;
/*
* We can iterate the block list also while sweep is in progress but we
(bl) = BLOCK_UNTAG ((bl));
#define END_FOREACH_BLOCK_NO_LOCK } SGEN_ARRAY_LIST_END_FOREACH_SLOT; }
+#define FOREACH_BLOCK_RANGE_HAS_REFERENCES_NO_LOCK(bl,begin,end,index,hr) { \
+ volatile gpointer *slot; \
+ SGEN_ARRAY_LIST_FOREACH_SLOT_RANGE (&allocated_blocks, begin, end, slot, index) { \
+ (bl) = (MSBlockInfo *) (*slot); \
+ if (!(bl)) \
+ continue; \
+ (hr) = BLOCK_IS_TAGGED_HAS_REFERENCES ((bl)); \
+ (bl) = BLOCK_UNTAG ((bl));
+#define END_FOREACH_BLOCK_RANGE_NO_LOCK } SGEN_ARRAY_LIST_END_FOREACH_SLOT_RANGE; }
+
static volatile size_t num_major_sections = 0;
/*
* One free block list for each block object size. We add and remove blocks from these
#endif
/* gcc 4.2.1 from xcode4 crashes on sgen_card_table_get_card_address () when this is enabled */
-#if defined(PLATFORM_MACOSX)
+#if defined(HOST_DARWIN)
#if MONO_GNUC_VERSION <= 40300
#undef PREFETCH_CARDS
#endif
sgen_workers_foreach (GENERATION_NURSERY, sgen_worker_clear_free_block_lists);
sgen_workers_foreach (GENERATION_OLD, sgen_worker_clear_free_block_lists);
+
+ compact_blocks = TRUE;
}
static void sweep_finish (void);
#endif
old_num_major_sections = num_major_sections;
+
+ /* Compact the block list if it hasn't been compacted in a while and nobody is using it */
+ if (compact_blocks && !sweep_in_progress () && !sweep_blocks_job && !sgen_concurrent_collection_in_progress ()) {
+ /*
+ * We support null elements in the array but do regular compaction to avoid
+ * excessive traversal of the array and to facilitate splitting into well
+ * balanced sections for parallel modes. We compact as soon as possible after
+ * sweep.
+ */
+ sgen_array_list_remove_nulls (&allocated_blocks);
+ compact_blocks = FALSE;
+ }
}
static void
}
static void
-major_scan_card_table (CardTableScanType scan_type, ScanCopyContext ctx, int job_index, int job_split_count)
+major_scan_card_table (CardTableScanType scan_type, ScanCopyContext ctx, int job_index, int job_split_count, int block_count)
{
MSBlockInfo *block;
gboolean has_references, was_sweeping, skip_scan;
+ int first_block, last_block, index;
+
+ /*
+ * The last_block's index is at least (num_major_sections - 1) since we
+ * can have nulls in the allocated_blocks list. The last worker will
+ * scan the left-overs of the list. We expect few null entries in the
+ * allocated_blocks list, therefore using num_major_sections for computing
+ * block_count shouldn't affect work distribution.
+ */
+ first_block = block_count * job_index;
+ if (job_index == job_split_count - 1)
+ last_block = allocated_blocks.next_slot;
+ else
+ last_block = block_count * (job_index + 1);
if (!concurrent_mark)
g_assert (scan_type == CARDTABLE_SCAN_GLOBAL);
was_sweeping = sweep_in_progress ();
binary_protocol_major_card_table_scan_start (sgen_timestamp (), scan_type & CARDTABLE_SCAN_MOD_UNION);
- FOREACH_BLOCK_HAS_REFERENCES_NO_LOCK (block, has_references) {
- if (__index % job_split_count != job_index)
- continue;
+ FOREACH_BLOCK_RANGE_HAS_REFERENCES_NO_LOCK (block, first_block, last_block, index, has_references) {
#ifdef PREFETCH_CARDS
- int prefetch_index = __index + 6 * job_split_count;
+ int prefetch_index = index + 6;
if (prefetch_index < allocated_blocks.next_slot) {
MSBlockInfo *prefetch_block = BLOCK_UNTAG (*sgen_array_list_get_slot (&allocated_blocks, prefetch_index));
PREFETCH_READ (prefetch_block);
}
}
#endif
-
if (!has_references)
continue;
skip_scan = FALSE;
* sweep start since we are in a nursery collection. Also avoid CAS-ing
*/
if (sweep_in_progress ()) {
- skip_scan = !ensure_block_is_checked_for_sweeping (__index, TRUE, NULL);
+ skip_scan = !ensure_block_is_checked_for_sweeping (index, TRUE, NULL);
} else if (was_sweeping) {
/* Recheck in case sweep finished after dereferencing the slot */
- skip_scan = *sgen_array_list_get_slot (&allocated_blocks, __index) == 0;
+ skip_scan = *sgen_array_list_get_slot (&allocated_blocks, index) == 0;
}
}
}
if (!skip_scan)
scan_card_table_for_block (block, scan_type, ctx);
- } END_FOREACH_BLOCK_NO_LOCK;
+ } END_FOREACH_BLOCK_RANGE_NO_LOCK;
binary_protocol_major_card_table_scan_end (sgen_timestamp (), scan_type & CARDTABLE_SCAN_MOD_UNION);
}