From: Tang Yizhou <yizhou.tang@shopee.com>
Date: Sun, 27 Jul 2025 17:39:57 +0000 (+0800)
Subject: blk-wbt: Optimize wbt_done() for non-throttled writes
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=d8b96a79622e03813c221450498ca9742704ebf2;p=users%2Fjedix%2Flinux-maple.git

blk-wbt: Optimize wbt_done() for non-throttled writes

In the current implementation, the sync_cookie and last_cookie members of
struct rq_wb are used only by read requests and not by non-throttled write
requests. Based on this, we can optimize wbt_done() by removing one if
condition check for non-throttled write requests.

Signed-off-by: Tang Yizhou <yizhou.tang@shopee.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20250727173959.160835-2-yizhou.tang@shopee.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/block/blk-wbt.c b/block/blk-wbt.c
index a50d4cd55f419..30886d44f6cd2 100644
--- a/block/blk-wbt.c
+++ b/block/blk-wbt.c
@@ -248,13 +248,14 @@ static void wbt_done(struct rq_qos *rqos, struct request *rq)
 	struct rq_wb *rwb = RQWB(rqos);
 
 	if (!wbt_is_tracked(rq)) {
-		if (rwb->sync_cookie == rq) {
-			rwb->sync_issue = 0;
-			rwb->sync_cookie = NULL;
-		}
+		if (wbt_is_read(rq)) {
+			if (rwb->sync_cookie == rq) {
+				rwb->sync_issue = 0;
+				rwb->sync_cookie = NULL;
+			}
 
-		if (wbt_is_read(rq))
 			wb_timestamp(rwb, &rwb->last_comp);
+		}
 	} else {
 		WARN_ON_ONCE(rq == rwb->sync_cookie);
 		__wbt_done(rqos, wbt_flags(rq));