linux-kernel - [PATCH] ublk: remove unnecessary ubq checks

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Message-ID: <20250416170154.3621609-1-csander@purestorage.com>
Date: Wed, 16 Apr 2025 11:01:53 -0600
From: Caleb Sander Mateos <csander@...estorage.com>
To: Ming Lei <ming.lei@...hat.com>,
	Jens Axboe <axboe@...nel.dk>
Cc: Caleb Sander Mateos <csander@...estorage.com>,
	linux-block@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH] ublk: remove unnecessary ubq checks

ublk_init_queues() ensures that all nr_hw_queues queues are initialized,
with each ublk_queue's q_id set to its index. And ublk_init_queues() is
called before ublk_add_chdev(), which creates the cdev. Is is therefore
impossible for the !ubq || ub_cmd->q_id != ubq->q_id condition to hit in
__ublk_ch_uring_cmd(). Remove it to avoids some branches in the I/O path.

Signed-off-by: Caleb Sander Mateos <csander@...estorage.com>
---
 drivers/block/ublk_drv.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index cdb1543fa4a9..bc86231f5e27 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -1947,13 +1947,10 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd,
 
 	if (ub_cmd->q_id >= ub->dev_info.nr_hw_queues)
 		goto out;
 
 	ubq = ublk_get_queue(ub, ub_cmd->q_id);
-	if (!ubq || ub_cmd->q_id != ubq->q_id)
-		goto out;
-
 	if (ubq->ubq_daemon && ubq->ubq_daemon != current)
 		goto out;
 
 	if (tag >= ubq->q_depth)
 		goto out;
-- 
2.45.2