From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B5532220F32; Sun, 17 Aug 2025 15:26:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755444410; cv=none; b=sww74r3vsvX/s00Z/qRHTlcmPvzhVpyAdp+t0b9Z3bZUsiD66r1TGRSguqr0AJ7xYVMh6hdgnh0Lkt81ZZl79JI6dyUn96Mx1yT9dc0xw4wX+YkRWgwjAgBuR2MhWCihCWnUEbd5eYaQnYmLcDSKQ8u4xnghAAz4OiUBv7djYw0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755444410; c=relaxed/simple; bh=5FojilEHVOyGFqyLozl5Yfp/KgFqqkGTgzbjJc21+Ak=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=Yw2BV885rh4VxQ+HAaaIlw059WjeZPqndTkqtxqr3NgYeM4CqthK3Yd/yTHS5rbuGws0y02FGrdYeNr84IchcQjtE1kmeVdUlcjWFIYg8l2dp592JCIFGACcnc8U6kEhH+3gFZ7RWnX+Mt1OXupjAIEwS6iX35BHuXLFuOj5P50= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CvM3yEW/; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="CvM3yEW/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0B593C4CEEB; Sun, 17 Aug 2025 15:26:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1755444410; bh=5FojilEHVOyGFqyLozl5Yfp/KgFqqkGTgzbjJc21+Ak=; h=From:To:Cc:Subject:Date:From; b=CvM3yEW/oGvQANsLJK8X54JoxEONAwmR55TpLoiJVZd+KDtIrQyUlMP2OHJ5zjEdp ej4bUU5fDa6D9Ie4IYiBIm5K0tAixxSAKeKtICEm9HvFSSmqQt+L65YxiRIhgskhcF XsGgLd46gWWN46B+4p36IqWdilo5ScRxIAfl3xD+DywHSjB00+JzyTDZeYJetzuh16 ghkXDEnkjd7GCPUGwZMTC3bVk0XpWANBf1rBdvmXi0QORmS0+Txgq1Wg93VzBv5GB9 Z3J7cNjgAiaLNs7FOqURhNBjE26RSXEKUOzmuB8CW0CQfnzVFh/kcAYDMEAUUArbBa Wl8WI23YHdb3A== From: colyli@kernel.org To: linux-raid@vger.kernel.org Cc: linux-block@vger.kernel.org, yukuai3@huawei.com, Coly Li Subject: [PATCH 1/2] block: ignore underlying non-stack devices io_opt Date: Sun, 17 Aug 2025 23:26:44 +0800 Message-ID: <20250817152645.7115-1-colyli@kernel.org> X-Mailer: git-send-email 2.47.2 Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Coly Li This patch adds a new BLK_FLAG_STACK_IO_OPT for stack block device. If a stack block device like md raid5 declares its io_opt when don't want blk_stack_limits() to change it with io_opt of underlying non-stack block devices, BLK_FLAG_STACK_IO_OPT can be set on limits.flags. Then in blk_stack_limits(), lcm_not_zero(t->io_opt, b->io_opt) will be avoided. For md raid5, it is necessary to keep a proper io_opt size for better I/O thoughput. Signed-off-by: Coly Li --- block/blk-settings.c | 6 +++++- drivers/md/raid5.c | 1 + include/linux/blkdev.h | 3 +++ 3 files changed, 9 insertions(+), 1 deletion(-) diff --git a/block/blk-settings.c b/block/blk-settings.c index 07874e9b609f..46ee538b2be9 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -782,6 +782,7 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, t->features &= ~BLK_FEAT_POLL; t->flags |= (b->flags & BLK_FLAG_MISALIGNED); + t->flags |= (b->flags & BLK_FLAG_STACK_IO_OPT); t->max_sectors = min_not_zero(t->max_sectors, b->max_sectors); t->max_user_sectors = min_not_zero(t->max_user_sectors, @@ -839,7 +840,10 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, b->physical_block_size); t->io_min = max(t->io_min, b->io_min); - t->io_opt = lcm_not_zero(t->io_opt, b->io_opt); + if (!t->io_opt || !(t->flags & BLK_FLAG_STACK_IO_OPT) || + (b->flags & BLK_FLAG_STACK_IO_OPT)) + t->io_opt = lcm_not_zero(t->io_opt, b->io_opt); + t->dma_alignment = max(t->dma_alignment, b->dma_alignment); /* Set non-power-of-2 compatible chunk_sectors boundary */ diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 023649fe2476..989acd8abd98 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -7730,6 +7730,7 @@ static int raid5_set_limits(struct mddev *mddev) lim.io_min = mddev->chunk_sectors << 9; lim.io_opt = lim.io_min * (conf->raid_disks - conf->max_degraded); lim.features |= BLK_FEAT_RAID_PARTIAL_STRIPES_EXPENSIVE; + lim.flags |= BLK_FLAG_STACK_IO_OPT; lim.discard_granularity = stripe; lim.max_write_zeroes_sectors = 0; mddev_stack_rdev_limits(mddev, &lim, 0); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 95886b404b16..a22c7cea9836 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -366,6 +366,9 @@ typedef unsigned int __bitwise blk_flags_t; /* passthrough command IO accounting */ #define BLK_FLAG_IOSTATS_PASSTHROUGH ((__force blk_flags_t)(1u << 2)) +/* ignore underlying non-stack devices io_opt */ +#define BLK_FLAG_STACK_IO_OPT ((__force blk_flags_t)(1u << 3)) + struct queue_limits { blk_features_t features; blk_flags_t flags; -- 2.47.2