block: Don't count_vm_events for discard bio in submit_bio.

In submit_bio, we count vm events by check READ/WRITE. But actually DISCARD_NOBARRIER also has the WRITE flag set. It looks as if in blkdev_issue_discard, we also add a page as the payload and the bio_has_data check isn't enough. So add another check for discard bio. Signed-off-by: Tao Ma <[email protected]> Signed-off-by: Jens Axboe <[email protected]>
noroot · Jun 24, 2010 · 1b99973 · 1b99973
1 parent 9e495db
commit 1b99973
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/block/blk-core.c b/block/blk-core.c
@@ -1583,7 +1583,7 @@ void submit_bio(int rw, struct bio *bio)
 	 * If it's a regular read/write or a barrier with data attached,
 	 * go through the normal accounting stuff before submission.
 	 */
-	if (bio_has_data(bio)) {
+	if (bio_has_data(bio) && !(rw & (1 << BIO_RW_DISCARD))) {
 		if (rw & WRITE) {
 			count_vm_events(PGPGOUT, count);
 		} else {