mm: vmscan: do not stall on writeback during memory compaction
This patch stops reclaim/compaction entering sync reclaim as this was
only intended for lumpy reclaim and an oversight. Page migration has
its own logic for stalling on writeback pages if necessary and memory
compaction is already using it.
Waiting on page writeback is bad for a number of reasons but the primary
one is that waiting on writeback to a slow device like USB can take a
considerable length of time. Page reclaim instead uses
wait_iff_congested() to throttle if too many dirty pages are being
scanned.
Change-Id: I14f312b1a51ee093d9d4adda5c87e57f1b83e03d
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ying Han <yinghan@google.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: 41ac1999c3e3563e1810b14878a869c79c9368bb
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
index 1c20a1f..c0e0b3b 100644
--- a/include/trace/events/vmscan.h
+++ b/include/trace/events/vmscan.h
@@ -13,7 +13,7 @@
#define RECLAIM_WB_ANON 0x0001u
#define RECLAIM_WB_FILE 0x0002u
#define RECLAIM_WB_MIXED 0x0010u
-#define RECLAIM_WB_SYNC 0x0004u
+#define RECLAIM_WB_SYNC 0x0004u /* Unused, all reclaim async */
#define RECLAIM_WB_ASYNC 0x0008u
#define show_reclaim_flags(flags) \
@@ -27,13 +27,13 @@
#define trace_reclaim_flags(page, sync) ( \
(page_is_file_cache(page) ? RECLAIM_WB_FILE : RECLAIM_WB_ANON) | \
- (sync & RECLAIM_MODE_SYNC ? RECLAIM_WB_SYNC : RECLAIM_WB_ASYNC) \
+ (RECLAIM_WB_ASYNC) \
)
-#define trace_shrink_flags(file, sync) ( \
- (sync & RECLAIM_MODE_SYNC ? RECLAIM_WB_MIXED : \
- (file ? RECLAIM_WB_FILE : RECLAIM_WB_ANON)) | \
- (sync & RECLAIM_MODE_SYNC ? RECLAIM_WB_SYNC : RECLAIM_WB_ASYNC) \
+#define trace_shrink_flags(file, sync) \
+ ( \
+ (file ? RECLAIM_WB_FILE : RECLAIM_WB_ANON) | \
+ (RECLAIM_WB_ASYNC) \
)
TRACE_EVENT(mm_vmscan_kswapd_sleep,