From nobody Sat Oct 4 14:36:15 2025 Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) (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 F0A2B27713; Fri, 15 Aug 2025 08:10:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755245411; cv=none; b=kXAbzvcvFGFt/vBFqWtxHEZY9NS3I0ETmf9/PxPISh0adDAlx9xTUIDJFAICfUIb1g0i+QMMnWryetb0fGpzFVYzVCcRatPkNPU2ualBFBjQqNIEVBFOMoHUsaTrY6HhkwtwzXwYg1UcUq1+hO1MgLxtVjkyZn0jDFkPw1BTeok= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755245411; c=relaxed/simple; bh=n6vReAJVtwzVAOe+TgrKwM2LSZah4lupyvFThnDLfB4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=etX7B9NSHPzYYrZ7k8vnxWclQifWQj9x8GGWzfsONV57CwRYuv1FIOoBMjoVDHScFAR+znEDnugNlQfLqG+CnBSpYZNcgGPjOv3O0YfgvCC9QP802+iUINLbHMFs7fCwa3dvnJJPlLuF+uYVBZeeD9eBA5PPpx0Z1+LO/+2qcBg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTPS id 4c3FCN20P6zYQv9D; Fri, 15 Aug 2025 16:10:08 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id DA08E1A0944; Fri, 15 Aug 2025 16:10:06 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP4 (Coremail) with SMTP id gCh0CgDHjxBc655o+xX_Dg--.53834S5; Fri, 15 Aug 2025 16:10:06 +0800 (CST) From: Yu Kuai To: axboe@kernel.dk, hare@suse.de, nilay@linux.ibm.com, ming.lei@redhat.com Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yukuai3@huawei.com, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com, johnny.chenyi@huawei.com Subject: [PATCH 01/10] blk-mq: remove useless checking from queue_requests_store() Date: Fri, 15 Aug 2025 16:02:07 +0800 Message-Id: <20250815080216.410665-2-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20250815080216.410665-1-yukuai1@huaweicloud.com> References: <20250815080216.410665-1-yukuai1@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: gCh0CgDHjxBc655o+xX_Dg--.53834S5 X-Coremail-Antispam: 1UD129KBjvdXoW7JrWxurW3KF13Aw47ZFy8Grg_yoWxtFg_GF y8Kry2qrsakF48Zr47Ar10qF4Ikw1rGF45WFWDJas5AFyfJa4fKrWrXryrAr43ua9rGa1r C3WxG34xGr40vjkaLaAFLSUrUUUUjb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUbkxFF20E14v26ryj6rWUM7CY07I20VC2zVCF04k26cxKx2IYs7xG 6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUGwA2048vs2IY02 0Ec7CjxVAFwI0_Gr0_Xr1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xv wVC0I7IYx2IY67AKxVWDJVCq3wA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxVW8Jr0_Cr1UM2 8EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AI xVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20x vE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xv r2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7M4IIrI8v6xkF7I0E8cxan2IY04 v7MxkF7I0En4kS14v26r1q6r43MxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j 6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7 AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE 2Ix0cI8IcVCY1x0267AKxVW8JVWxJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcV C2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2Kfnx nUUI43ZEXa7VUjnXo7UUUUU== X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ Content-Type: text/plain; charset="utf-8" From: Yu Kuai blk_mq_queue_attr_visible() already checked queue_is_mq(), no need to check this again in queue_requests_store(). Signed-off-by: Yu Kuai --- block/blk-sysfs.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index c5cf79a20842..1086f7b9da28 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -69,9 +69,6 @@ queue_requests_store(struct gendisk *disk, const char *pa= ge, size_t count) unsigned int memflags; struct request_queue *q =3D disk->queue; =20 - if (!queue_is_mq(q)) - return -EINVAL; - ret =3D queue_var_store(&nr, page, count); if (ret < 0) return ret; --=20 2.39.2 From nobody Sat Oct 4 14:36:15 2025 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) (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 A047329CE1; Fri, 15 Aug 2025 08:10:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.56 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755245412; cv=none; b=I6fcOW3tIXRpL7WV5WgN8K3aZHxoujarFEGo/fOilLBy8ZdQ8ep4vcltF+Xds9GT+TPnL1Me0K3bN/uOG7rGbPsT0Hx1qVMQzmgpRXbZlsqJncVH0b3HUUnChJk0yVN61j/w3htORo0O2tH9QqfCFH1HS5C5r86Oj6IYKReWjg4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755245412; c=relaxed/simple; bh=R18nirD9dQXB8+w06HH8waupCvAqpHeMtq644QFOOm4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Y55S1awIbN8pkzxfDmL1cIetkwGK3jYs2YzjM85UFVELR6omP2UE3Vio5W73Rv+KCtMydZaceFHPym58QcNpkWYppuzTg2HvMUsK9ePWq0nNzgLMUZ+noP7WogJhoNFRkzxomlxS1Y2/hvvTdzYGZcvy1ooK4udxq9ERxdSYFpU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTPS id 4c3FCN0cLmzKHMTP; Fri, 15 Aug 2025 16:10:08 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id 62A3B1A0B00; Fri, 15 Aug 2025 16:10:07 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP4 (Coremail) with SMTP id gCh0CgDHjxBc655o+xX_Dg--.53834S6; Fri, 15 Aug 2025 16:10:07 +0800 (CST) From: Yu Kuai To: axboe@kernel.dk, hare@suse.de, nilay@linux.ibm.com, ming.lei@redhat.com Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yukuai3@huawei.com, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com, johnny.chenyi@huawei.com Subject: [PATCH 02/10] blk-mq: remove useless checkings from blk_mq_update_nr_requests() Date: Fri, 15 Aug 2025 16:02:08 +0800 Message-Id: <20250815080216.410665-3-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20250815080216.410665-1-yukuai1@huaweicloud.com> References: <20250815080216.410665-1-yukuai1@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: gCh0CgDHjxBc655o+xX_Dg--.53834S6 X-Coremail-Antispam: 1UD129KBjvdXoWrtw13XF4fZrW8XFyrtw17trb_yoWDKrX_CF y0kF92qrs5Jr4SvwsFk3WYvFy8Gw1DJF4fGas8tr9rXr1kGFsxJrWDGr15WFsrW3y3C3Z7 u3WUWw43Jw4SvjkaLaAFLSUrUUUUjb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUbkkFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k26cxKx2IYs7xG 6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUXwA2048vs2IY02 0Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xv wVC0I7IYx2IY67AKxVWDJVCq3wA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxVW8Jr0_Cr1UM2 8EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AI xVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20x vE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xv r2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7M4IIrI8v6xkF7I0E8cxan2IY04 v7MxkF7I0En4kS14v26r1q6r43MxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j 6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7 AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE 2Ix0cI8IcVCY1x0267AKxVW8JVWxJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcV C2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8Jr0_Cr1UYxBIdaVFxhVj vjDU0xZFpf9x0JUQXo7UUUUU= X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ Content-Type: text/plain; charset="utf-8" From: Yu Kuai 1) queue_requests_store() is the only caller of blk_mq_update_nr_requests(), where queue is already freezed, no need to check mq_freeze_depth; 2) q->tag_set must be set for request_based device, and queue_is_mq() is already checked in blk_mq_queue_attr_visible(), no need to check q->tag_set. Signed-off-by: Yu Kuai --- block/blk-mq.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 9c68749124c6..ea2995d4a917 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -4921,21 +4921,14 @@ int blk_mq_update_nr_requests(struct request_queue = *q, unsigned int nr) { struct blk_mq_tag_set *set =3D q->tag_set; struct blk_mq_hw_ctx *hctx; - int ret; unsigned long i; - - if (WARN_ON_ONCE(!q->mq_freeze_depth)) - return -EINVAL; - - if (!set) - return -EINVAL; + int ret =3D 0; =20 if (q->nr_requests =3D=3D nr) return 0; =20 blk_mq_quiesce_queue(q); =20 - ret =3D 0; queue_for_each_hw_ctx(q, hctx, i) { if (!hctx->tags) continue; --=20 2.39.2 From nobody Sat Oct 4 14:36:15 2025 Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) (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 B452D22A4F4; Fri, 15 Aug 2025 08:10:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755245413; cv=none; b=OLylbfoVDVtVbdfFbPAysiAZPBkBRWwdYco83QZXNA1gxNflORlRNL0i6HB+aSygJgA5ZciHKdlz3QTSWL0mWDECXHNLgybM1tBX3G7x4QyYEWRbMzZHt4II7Dw0KSbRV6vzc/LSiuly3oPFTXRcdNJ7ga25+tJk9GAmb5GDdo8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755245413; c=relaxed/simple; bh=tPjvK34gtrEM/6/bXb5krqbiMLCUdkfP6Zlb/SvP00M=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=qnl8qrvQtxr8PyzU5E12QzWzsp8nvQ7yDlfOXoSn7xEF9czz1ESwP7hqia3TnsdZk09x3eSvCIeEhM/jIpCyl5IixEofAgetKZUJQHyU72chgNNzpgE8mnoYggVBGtr8DS8egPLRjErCCevZcAju9KIWyZCmgs+Ial+OBglKkbs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.93.142]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTPS id 4c3FCP1sbnzYQv9M; Fri, 15 Aug 2025 16:10:09 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id D4B6D1A018D; Fri, 15 Aug 2025 16:10:07 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP4 (Coremail) with SMTP id gCh0CgDHjxBc655o+xX_Dg--.53834S7; Fri, 15 Aug 2025 16:10:07 +0800 (CST) From: Yu Kuai To: axboe@kernel.dk, hare@suse.de, nilay@linux.ibm.com, ming.lei@redhat.com Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yukuai3@huawei.com, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com, johnny.chenyi@huawei.com Subject: [PATCH 03/10] blk-mq: check invalid nr_requests in queue_requests_store() Date: Fri, 15 Aug 2025 16:02:09 +0800 Message-Id: <20250815080216.410665-4-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20250815080216.410665-1-yukuai1@huaweicloud.com> References: <20250815080216.410665-1-yukuai1@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: gCh0CgDHjxBc655o+xX_Dg--.53834S7 X-Coremail-Antispam: 1UD129KBjvJXoWxCF4ruw1rXr45Kr17urWfXwb_yoWrCr4rpF W5KanFk340qr10vFWIyay7Xw1Fkws5Kr1xGFsaqa4avr1jkr4xXF1FqrWrXrW0yrWkCF47 Zr4DtrW5JF1kGrDanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUmY14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JrWl82xGYIkIc2 x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJw A2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq3wAS 0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2 IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0 Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2kIc2 xKxwCY1x0262kKe7AKxVWUtVW8ZwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWU JVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67 kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY 6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0x vEx4A2jsIE14v26r4j6F4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr1j6F4UJbIYCTnIWIev Ja73UjIFyTuYvjfUO_MaUUUUU X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ Content-Type: text/plain; charset="utf-8" From: Yu Kuai queue_requests_store() is the only caller of blk_mq_update_nr_requests(), and blk_mq_update_nr_requests() is the only caller of blk_mq_tag_update_depth(), however, they all have checkings for nr_requests input by user. Make code cleaner by moving all the checkings to the top function: 1) nr_requests > reserved tags; 2) if there is elevator, 4 <=3D nr_requests <=3D 2048; 3) if elevator is none, 4 <=3D nr_requests < tag_set->queue_depth; Meanwhile, case 2 is the only case tags can grow and -ENOMEM might be returned. Signed-off-by: Yu Kuai --- block/blk-mq-tag.c | 16 +--------------- block/blk-mq.c | 13 ++++--------- block/blk-mq.h | 2 +- block/blk-sysfs.c | 13 +++++++++++++ 4 files changed, 19 insertions(+), 25 deletions(-) diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index d880c50629d6..7613a9889eb1 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -584,14 +584,10 @@ void blk_mq_free_tags(struct blk_mq_tags *tags) } =20 int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx, - struct blk_mq_tags **tagsptr, unsigned int tdepth, - bool can_grow) + struct blk_mq_tags **tagsptr, unsigned int tdepth) { struct blk_mq_tags *tags =3D *tagsptr; =20 - if (tdepth <=3D tags->nr_reserved_tags) - return -EINVAL; - /* * If we are allowed to grow beyond the original size, allocate * a new set of tags before freeing the old one. @@ -600,16 +596,6 @@ int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx, struct blk_mq_tag_set *set =3D hctx->queue->tag_set; struct blk_mq_tags *new; =20 - if (!can_grow) - return -EINVAL; - - /* - * We need some sort of upper limit, set it high enough that - * no valid use cases should require more. - */ - if (tdepth > MAX_SCHED_RQ) - return -EINVAL; - /* * Only the sbitmap needs resizing since we allocated the max * initially. diff --git a/block/blk-mq.c b/block/blk-mq.c index ea2995d4a917..048d6b2cffe6 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -4924,9 +4924,6 @@ int blk_mq_update_nr_requests(struct request_queue *q= , unsigned int nr) unsigned long i; int ret =3D 0; =20 - if (q->nr_requests =3D=3D nr) - return 0; - blk_mq_quiesce_queue(q); =20 queue_for_each_hw_ctx(q, hctx, i) { @@ -4936,13 +4933,11 @@ int blk_mq_update_nr_requests(struct request_queue = *q, unsigned int nr) * If we're using an MQ scheduler, just update the scheduler * queue depth. This is similar to what the old code would do. */ - if (hctx->sched_tags) { + if (hctx->sched_tags) ret =3D blk_mq_tag_update_depth(hctx, &hctx->sched_tags, - nr, true); - } else { - ret =3D blk_mq_tag_update_depth(hctx, &hctx->tags, nr, - false); - } + nr); + else + ret =3D blk_mq_tag_update_depth(hctx, &hctx->tags, nr); if (ret) goto out; } diff --git a/block/blk-mq.h b/block/blk-mq.h index affb2e14b56e..2b3ade60c90b 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -171,7 +171,7 @@ void blk_mq_put_tag(struct blk_mq_tags *tags, struct bl= k_mq_ctx *ctx, unsigned int tag); void blk_mq_put_tags(struct blk_mq_tags *tags, int *tag_array, int nr_tags= ); int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx, - struct blk_mq_tags **tags, unsigned int depth, bool can_grow); + struct blk_mq_tags **tags, unsigned int depth); void blk_mq_tag_resize_shared_tags(struct blk_mq_tag_set *set, unsigned int size); void blk_mq_tag_update_sched_shared_tags(struct request_queue *q); diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 1086f7b9da28..f3d08edcc34f 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -75,12 +75,25 @@ queue_requests_store(struct gendisk *disk, const char *= page, size_t count) =20 memflags =3D blk_mq_freeze_queue(q); 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charset="utf-8" From: Yu Kuai request_queue->nr_requests can be changed by: a) switching elevator by update nr_hw_queues b) switching elevator by elevator sysfs attribute c) configue queue sysfs attribute nr_requests Current lock order is: 1) update_nr_hwq_lock, case a,b - allocate elevator tags 2) freeze_queue 3) elevator_lock, cas a,b,c - update nr_requests The update_nr_hwq_lock is not held by case c for now, and we need to check nr_requests while elevator_lock is held, however, we can't allocate elevator_tags whih queue freezed. Hence also require update_nr_hwq_lock and check nr_requests, make it possible to allocate new elevator_tags without queue freezed, also prevent nr_requests to be changed concurrently by other contexts. Signed-off-by: Yu Kuai --- block/blk-sysfs.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index f3d08edcc34f..37eae7927b45 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -68,13 +68,14 @@ queue_requests_store(struct gendisk *disk, const char *= page, size_t count) int ret, err; unsigned int memflags; struct request_queue *q =3D disk->queue; + struct blk_mq_tag_set *set =3D q->tag_set; =20 ret =3D queue_var_store(&nr, page, count); if (ret < 0) return ret; =20 - memflags =3D blk_mq_freeze_queue(q); - mutex_lock(&q->elevator_lock); + /* serialize with switching elevator */ + down_write(&set->update_nr_hwq_lock); =20 if (q->nr_requests =3D=3D nr) goto unlock; @@ -89,13 +90,17 @@ queue_requests_store(struct gendisk *disk, const char *= page, size_t count) goto unlock; } =20 + memflags =3D blk_mq_freeze_queue(q); + mutex_lock(&q->elevator_lock); err =3D blk_mq_update_nr_requests(disk->queue, nr); if (err) ret =3D err; 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Fri, 15 Aug 2025 16:10:08 +0800 (CST) From: Yu Kuai To: axboe@kernel.dk, hare@suse.de, nilay@linux.ibm.com, ming.lei@redhat.com Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yukuai3@huawei.com, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com, johnny.chenyi@huawei.com Subject: [PATCH 05/10] blk-mq: cleanup shared tags case in blk_mq_update_nr_requests() Date: Fri, 15 Aug 2025 16:02:11 +0800 Message-Id: <20250815080216.410665-6-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20250815080216.410665-1-yukuai1@huaweicloud.com> References: <20250815080216.410665-1-yukuai1@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: gCh0CgDHjxBc655o+xX_Dg--.53834S9 X-Coremail-Antispam: 1UD129KBjvJXoW7Cr1rWrWUuF1xZr17Cr1UAwb_yoW5JFWrpF Waka13K34Fqr1avFWav39xXw4Ygrs3Wr1SkrsxtryFqr12kF4xGF4rWr1rXFW8trZ5AFsI 9F4DJFWUXr18W37anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUma14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF0E3s1l82xGYI kIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2 z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F 4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq 3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7 IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4U M4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2 kIc2xKxwCY1x0262kKe7AKxVWUtVW8ZwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkE bVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67 AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUCVW8JwCI 42IY6xIIjxv20xvEc7CjxVAFwI0_Cr0_Gr1UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCw CI42IY6I8E87Iv67AKxVW8JVWxJwCI42IY6I8E87Iv6xkF7I0E14v26r4UJVWxJrUvcSsG vfC2KfnxnUUI43ZEXa7VUbPC7UUUUUU== X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ Content-Type: text/plain; charset="utf-8" From: Yu Kuai For shared tags case, all hctx->shared_tags/tags are the same, it doesn't make sense to call blk_mq_tag_update_depth() multiple times for the same tags. Signed-off-by: Yu Kuai --- block/blk-mq-tag.c | 7 ------- block/blk-mq.c | 42 ++++++++++++++++++++++-------------------- 2 files changed, 22 insertions(+), 27 deletions(-) diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index 7613a9889eb1..84a452e708e4 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -596,13 +596,6 @@ int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx, struct blk_mq_tag_set *set =3D hctx->queue->tag_set; struct blk_mq_tags *new; =20 - /* - * Only the sbitmap needs resizing since we allocated the max - * initially. - */ - if (blk_mq_is_shared_tags(set->flags)) - return 0; - new =3D blk_mq_alloc_map_and_rqs(set, hctx->queue_num, tdepth); if (!new) return -ENOMEM; diff --git a/block/blk-mq.c b/block/blk-mq.c index 048d6b2cffe6..1e85fcd474c2 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -4926,33 +4926,35 @@ int blk_mq_update_nr_requests(struct request_queue = *q, unsigned int nr) =20 blk_mq_quiesce_queue(q); =20 - queue_for_each_hw_ctx(q, hctx, i) { - if (!hctx->tags) - continue; - /* - * If we're using an MQ scheduler, just update the scheduler - * queue depth. This is similar to what the old code would do. - */ - if (hctx->sched_tags) - ret =3D blk_mq_tag_update_depth(hctx, &hctx->sched_tags, - nr); - else - ret =3D blk_mq_tag_update_depth(hctx, &hctx->tags, nr); - if (ret) - goto out; - } - - q->nr_requests =3D nr; - if (q->elevator && q->elevator->type->ops.depth_updated) - q->elevator->type->ops.depth_updated(q); - if (blk_mq_is_shared_tags(set->flags)) { if (q->elevator) blk_mq_tag_update_sched_shared_tags(q); else blk_mq_tag_resize_shared_tags(set, nr); + } else { + queue_for_each_hw_ctx(q, hctx, i) { + if (!hctx->tags) + continue; + /* + * If we're using an MQ scheduler, just update the + * scheduler queue depth. This is similar to what the + * old code would do. + */ + if (hctx->sched_tags) + ret =3D blk_mq_tag_update_depth(hctx, + &hctx->sched_tags, nr); + else + ret =3D blk_mq_tag_update_depth(hctx, + &hctx->tags, nr); + if (ret) + goto out; + } } =20 + q->nr_requests =3D nr; + if (q->elevator && q->elevator->type->ops.depth_updated) + q->elevator->type->ops.depth_updated(q); + out: blk_mq_unquiesce_queue(q); =20 --=20 2.39.2 From nobody Sat Oct 4 14:36:15 2025 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) (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 E4CFE2BDC09; Fri, 15 Aug 2025 08:10:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.56 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755245414; cv=none; b=Ff8396EJ/mNRN7SfMmGBeJIPYo+3tEnSTXdn3NNNWZhLVXaIEvFw8wS1H5hixuMWoVdYAqaYVDMLgJ2PoErNnQcIiHCaauRwr/+7WVeL7U0K2IvAUQEA4vGMWpg0baQLC48qm2fl0OAvHFR2IrwxC4VjSVVYMH+gFdDj+GRY9ks= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755245414; c=relaxed/simple; bh=JvyIOwpLHAkd49CL8/fvocRVASWsFuJRSncCBdL3grU=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=CsWUykXOKqRilIdiDtBXGGWVIKI96bubnSMS2D8f04zTEgftAXMxV0FV91GPXhRuByHJiU0PIfJMMiahKLn4Rfc/C78n3g3wOyxcjzk0K9KFP9HatRpBck7oNXIZqeS9MR2nOOE2cfS6nI894aSsj8D60jyeti1b069Brzen9AI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTPS id 4c3FCP6yW2zKHMjH; Fri, 15 Aug 2025 16:10:09 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id 491C11A0F34; Fri, 15 Aug 2025 16:10:09 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP4 (Coremail) with SMTP id gCh0CgDHjxBc655o+xX_Dg--.53834S10; Fri, 15 Aug 2025 16:10:09 +0800 (CST) From: Yu Kuai To: axboe@kernel.dk, hare@suse.de, nilay@linux.ibm.com, ming.lei@redhat.com Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yukuai3@huawei.com, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com, johnny.chenyi@huawei.com Subject: [PATCH 06/10] blk-mq: split bitmap grow and resize case in blk_mq_update_nr_requests() Date: Fri, 15 Aug 2025 16:02:12 +0800 Message-Id: <20250815080216.410665-7-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20250815080216.410665-1-yukuai1@huaweicloud.com> References: <20250815080216.410665-1-yukuai1@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: gCh0CgDHjxBc655o+xX_Dg--.53834S10 X-Coremail-Antispam: 1UD129KBjvJXoW7ZrWkXF18Ww1xJr4DWF17KFg_yoW8Xw18pF Wa9a1ak3sYqr15ZFWIqasrX3ZYgFs3XF1Syr4ftFyFgr10gr4agw4Sgr9xXFy8trZ3CayS krs8trWvyr1UXrUanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUma14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF0E3s1l82xGYI kIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2 z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F 4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq 3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7 IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4U M4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2 kIc2xKxwCY1x0262kKe7AKxVWUtVW8ZwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkE bVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67 AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUCVW8JwCI 42IY6xIIjxv20xvEc7CjxVAFwI0_Cr0_Gr1UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCw CI42IY6I8E87Iv67AKxVW8JVWxJwCI42IY6I8E87Iv6xkF7I0E14v26r4UJVWxJrUvcSsG vfC2KfnxnUUI43ZEXa7VUbPC7UUUUUU== X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ Content-Type: text/plain; charset="utf-8" From: Yu Kuai No functional changes are intended, make code cleaner and prepare to fix the grow case in following patches. Signed-off-by: Yu Kuai --- block/blk-mq.c | 27 ++++++++++++++++----------- 1 file changed, 16 insertions(+), 11 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 1e85fcd474c2..11c8baebb9a0 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -4931,21 +4931,26 @@ int blk_mq_update_nr_requests(struct request_queue = *q, unsigned int nr) blk_mq_tag_update_sched_shared_tags(q); else blk_mq_tag_resize_shared_tags(set, nr); + } else if (!q->elevator) { + queue_for_each_hw_ctx(q, hctx, i) { + if (!hctx->tags) + continue; + sbitmap_queue_resize(&hctx->tags->bitmap_tags, + nr - hctx->tags->nr_reserved_tags); + } + } else if (nr <=3D q->elevator->et->nr_requests) { + queue_for_each_hw_ctx(q, hctx, i) { + if (!hctx->tags) + continue; + sbitmap_queue_resize(&hctx->sched_tags->bitmap_tags, + nr - hctx->sched_tags->nr_reserved_tags); + } } else { queue_for_each_hw_ctx(q, hctx, i) { if (!hctx->tags) continue; - /* - * If we're using an MQ scheduler, just update the - * scheduler queue depth. This is similar to what the - * old code would do. - */ - if (hctx->sched_tags) - ret =3D blk_mq_tag_update_depth(hctx, - &hctx->sched_tags, nr); - else - ret =3D blk_mq_tag_update_depth(hctx, - &hctx->tags, nr); + ret =3D blk_mq_tag_update_depth(hctx, &hctx->sched_tags, + nr); if (ret) goto out; } --=20 2.39.2 From nobody Sat Oct 4 14:36:15 2025 Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) (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 EE54B2BE7A5; Fri, 15 Aug 2025 08:10:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755245415; cv=none; b=D2aQx2bd2pnz5JCVT1vMCNND/FdNWVFVujHs4OUpmA8jHizPz4C3o/jjZSof9o4tQRaqWL5Fq2rDbzOykDHEiavP3WmEopeD/oXic5y08O4CzztjtZhiHQT84RjWM4dm+iWuAT3PaX5XNDMaAKh+MmLc6NCuR9A5F+eOCUYJjfw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755245415; c=relaxed/simple; bh=b7q9FadDpEqvIWgtR4RG1TD0ZhvjfE4IXJ380E9G/U8=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=IJj9661qrQ4DqdQz7jXNjHjAnW0PmBUKst97cFqasyEvevA65gMSL7ws12g4gmEeeZay3s2/vzJZgbxDvI409LvkM75ClxiJ5nQcI1mrIywfwt0Um/EhA4P1C2rK1on3vCm01MPvIu19+AMXZpFWZ3vk65y4bn/gd6iyTAbGoHE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTPS id 4c3FCR1LR1zYQv9d; Fri, 15 Aug 2025 16:10:11 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id C19741A0F71; Fri, 15 Aug 2025 16:10:09 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP4 (Coremail) with SMTP id gCh0CgDHjxBc655o+xX_Dg--.53834S11; Fri, 15 Aug 2025 16:10:09 +0800 (CST) From: Yu Kuai To: axboe@kernel.dk, hare@suse.de, nilay@linux.ibm.com, ming.lei@redhat.com Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yukuai3@huawei.com, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com, johnny.chenyi@huawei.com Subject: [PATCH 07/10] blk-mq-sched: add new parameter nr_requests in blk_mq_alloc_sched_tags() Date: Fri, 15 Aug 2025 16:02:13 +0800 Message-Id: <20250815080216.410665-8-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20250815080216.410665-1-yukuai1@huaweicloud.com> References: <20250815080216.410665-1-yukuai1@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: gCh0CgDHjxBc655o+xX_Dg--.53834S11 X-Coremail-Antispam: 1UD129KBjvJXoWxJw48trWUGr1UuFW3ZFyrJFb_yoWrGF1kpF 45Xa12k3yYqr1kXay2y3yfXr13tws29FyxGr4ft34Fyr1q9ws3WF18WrWUXrW0yrZ3AFsF yr1Dtay5XrsFg3DanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUma14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF0E3s1l82xGYI kIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2 z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F 4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq 3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7 IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4U M4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2 kIc2xKxwCY1x0262kKe7AKxVWUtVW8ZwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkE bVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67 AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUCVW8JwCI 42IY6xIIjxv20xvEc7CjxVAFwI0_Cr0_Gr1UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCw CI42IY6I8E87Iv67AKxVW8JVWxJwCI42IY6I8E87Iv6xkF7I0E14v26r4UJVWxJrUvcSsG vfC2KfnxnUUI43ZEXa7VUbPC7UUUUUU== X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ Content-Type: text/plain; charset="utf-8" From: Yu Kuai This helper only support to allocate the default number of requests, add a new parameter to support specific number of requests. Prepare to fix tags double free problem if nr_requests is grown by queue sysfs attribute nr_requests. Signed-off-by: Yu Kuai --- block/blk-mq-sched.c | 14 +++++--------- block/blk-mq-sched.h | 2 +- block/blk-mq.h | 11 +++++++++++ block/elevator.c | 3 ++- 4 files changed, 19 insertions(+), 11 deletions(-) diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index bf7dd97422ec..f3a918e36589 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -454,7 +454,7 @@ void blk_mq_free_sched_tags_batch(struct xarray *et_tab= le, } =20 struct elevator_tags *blk_mq_alloc_sched_tags(struct blk_mq_tag_set *set, - unsigned int nr_hw_queues) + unsigned int nr_hw_queues, unsigned int nr_requests) { unsigned int nr_tags; int i; @@ -470,13 +470,8 @@ struct elevator_tags *blk_mq_alloc_sched_tags(struct b= lk_mq_tag_set *set, nr_tags * sizeof(struct blk_mq_tags *), gfp); if (!et) return NULL; - /* - * Default to double of smaller one between hw queue_depth and - * 128, since we don't split into sync/async like the old code - * did. Additionally, this is a per-hw queue depth. - */ - et->nr_requests =3D 2 * min_t(unsigned int, set->queue_depth, - BLKDEV_DEFAULT_RQ); + + et->nr_requests =3D nr_requests; et->nr_hw_queues =3D nr_hw_queues; =20 if (blk_mq_is_shared_tags(set->flags)) { @@ -521,7 +516,8 @@ int blk_mq_alloc_sched_tags_batch(struct xarray *et_tab= le, * concurrently. */ if (q->elevator) { - et =3D blk_mq_alloc_sched_tags(set, nr_hw_queues); + et =3D blk_mq_alloc_sched_tags(set, nr_hw_queues, + blk_mq_default_nr_requests(set)); if (!et) goto out_unwind; if (xa_insert(et_table, q->id, et, gfp)) diff --git a/block/blk-mq-sched.h b/block/blk-mq-sched.h index fe83187f41db..8e21a6b1415d 100644 --- a/block/blk-mq-sched.h +++ b/block/blk-mq-sched.h @@ -24,7 +24,7 @@ void blk_mq_exit_sched(struct request_queue *q, struct el= evator_queue *e); void blk_mq_sched_free_rqs(struct request_queue *q); =20 struct elevator_tags *blk_mq_alloc_sched_tags(struct blk_mq_tag_set *set, - unsigned int nr_hw_queues); + unsigned int nr_hw_queues, unsigned int nr_requests); int blk_mq_alloc_sched_tags_batch(struct xarray *et_table, struct blk_mq_tag_set *set, unsigned int nr_hw_queues); void blk_mq_free_sched_tags(struct elevator_tags *et, diff --git a/block/blk-mq.h b/block/blk-mq.h index 2b3ade60c90b..731f4578d9a8 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -109,6 +109,17 @@ static inline struct blk_mq_hw_ctx *blk_mq_map_queue(b= lk_opf_t opf, return ctx->hctxs[blk_mq_get_hctx_type(opf)]; } =20 +/* + * Default to double of smaller one between hw queue_depth and + * 128, since we don't split into sync/async like the old code + * did. Additionally, this is a per-hw queue depth. + */ +static inline unsigned int blk_mq_default_nr_requests( + struct blk_mq_tag_set *set) +{ + return 2 * min_t(unsigned int, set->queue_depth, BLKDEV_DEFAULT_RQ); +} + /* * sysfs helpers */ diff --git a/block/elevator.c b/block/elevator.c index fe96c6f4753c..e2ebfbf107b3 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -669,7 +669,8 @@ static int elevator_change(struct request_queue *q, str= uct elv_change_ctx *ctx) lockdep_assert_held(&set->update_nr_hwq_lock); =20 if (strncmp(ctx->name, "none", 4)) { - ctx->et =3D blk_mq_alloc_sched_tags(set, set->nr_hw_queues); + ctx->et =3D blk_mq_alloc_sched_tags(set, set->nr_hw_queues, + blk_mq_default_nr_requests(set)); if (!ctx->et) return -ENOMEM; } --=20 2.39.2 From nobody Sat Oct 4 14:36:15 2025 Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) (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 ACFBB2C325D; 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dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.93.142]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTPS id 4c3FCR4npxzYQv9C; Fri, 15 Aug 2025 16:10:11 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id 456251A07BB; Fri, 15 Aug 2025 16:10:10 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP4 (Coremail) with SMTP id gCh0CgDHjxBc655o+xX_Dg--.53834S12; Fri, 15 Aug 2025 16:10:10 +0800 (CST) From: Yu Kuai To: axboe@kernel.dk, hare@suse.de, nilay@linux.ibm.com, ming.lei@redhat.com Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yukuai3@huawei.com, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com, johnny.chenyi@huawei.com Subject: [PATCH 08/10] blk-mq: fix blk_mq_tags double free while nr_requests grown Date: Fri, 15 Aug 2025 16:02:14 +0800 Message-Id: <20250815080216.410665-9-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20250815080216.410665-1-yukuai1@huaweicloud.com> References: <20250815080216.410665-1-yukuai1@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: gCh0CgDHjxBc655o+xX_Dg--.53834S12 X-Coremail-Antispam: 1UD129KBjvJXoWxur13Xr1ruF1rZFy3Xr1kXwb_yoWrtF1xpF W5Ga1ak3yFqr18Za4UAw47XwnxKw4vgr17GrWft34F9rnrKr4xZF18GF48XFWIyrWkCFsF kr1DJrZ8ZrZ7Xa7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUma14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF0E3s1l82xGYI kIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2 z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F 4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq 3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7 IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4U M4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2 kIc2xKxwCY1x0262kKe7AKxVWUtVW8ZwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkE bVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67 AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUCVW8JwCI 42IY6xIIjxv20xvEc7CjxVAFwI0_Cr0_Gr1UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCw CI42IY6I8E87Iv67AKxVW8JVWxJwCI42IY6I8E87Iv6xkF7I0E14v26r4UJVWxJrUvcSsG vfC2KfnxnUUI43ZEXa7VUbPC7UUUUUU== X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ Content-Type: text/plain; charset="utf-8" From: Yu Kuai In the case user trigger tags grow by queue sysfs attribute nr_requests, hctx->sched_tags will be freed directly and replaced with a new allocated tags, see blk_mq_tag_update_depth(). The problem is that hctx->sched_tags is from elevator->et->tags, while et->tags is still the freed tags, hence later elevator exist will try to free the tags again, causing kernel panic. Fix this problem by using new allocated elevator_tags, also convert blk_mq_update_nr_requests to void since this helper will never fail now. Meanwhile, there is a longterm problem can be fixed as well: If blk_mq_tag_update_depth() succeed for previous hctx, then bitmap depth is updated, however, if following hctx failed, q->nr_requests is not updated and the previous hctx->sched_tags endup bigger than q->nr_requests. Fixes: f5a6604f7a44 ("block: fix lockdep warning caused by lock dependency = in elv_iosched_store") Fixes: e3a2b3f931f5 ("blk-mq: allow changing of queue depth through sysfs") Signed-off-by: Yu Kuai --- block/blk-mq.c | 19 ++++++------------- block/blk-mq.h | 4 +++- block/blk-sysfs.c | 21 ++++++++++++++------- 3 files changed, 23 insertions(+), 21 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 11c8baebb9a0..e9f037a25fe3 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -4917,12 +4917,12 @@ void blk_mq_free_tag_set(struct blk_mq_tag_set *set) } EXPORT_SYMBOL(blk_mq_free_tag_set); =20 -int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) +void blk_mq_update_nr_requests(struct request_queue *q, + struct elevator_tags *et, unsigned int nr) { struct blk_mq_tag_set *set =3D q->tag_set; struct blk_mq_hw_ctx *hctx; unsigned long i; - int ret =3D 0; =20 blk_mq_quiesce_queue(q); =20 @@ -4946,24 +4946,17 @@ int blk_mq_update_nr_requests(struct request_queue = *q, unsigned int nr) nr - hctx->sched_tags->nr_reserved_tags); } } else { - queue_for_each_hw_ctx(q, hctx, i) { - if (!hctx->tags) - continue; - ret =3D blk_mq_tag_update_depth(hctx, &hctx->sched_tags, - nr); - if (ret) - goto out; - } + blk_mq_free_sched_tags(q->elevator->et, set); + queue_for_each_hw_ctx(q, hctx, i) + hctx->sched_tags =3D et->tags[i]; + q->elevator->et =3D et; } =20 q->nr_requests =3D nr; if (q->elevator && q->elevator->type->ops.depth_updated) q->elevator->type->ops.depth_updated(q); =20 -out: blk_mq_unquiesce_queue(q); - - return ret; } =20 /* diff --git a/block/blk-mq.h b/block/blk-mq.h index 731f4578d9a8..98740f9c204e 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -6,6 +6,7 @@ #include "blk-stat.h" =20 struct blk_mq_tag_set; +struct elevator_tags; =20 struct blk_mq_ctxs { struct kobject kobj; @@ -45,7 +46,8 @@ void blk_mq_submit_bio(struct bio *bio); int blk_mq_poll(struct request_queue *q, blk_qc_t cookie, struct io_comp_b= atch *iob, unsigned int flags); void blk_mq_exit_queue(struct request_queue *q); -int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr); +void blk_mq_update_nr_requests(struct request_queue *q, + struct elevator_tags *et, unsigned int nr); void blk_mq_wake_waiters(struct request_queue *q); bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head = *, bool); diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 37eae7927b45..848648456255 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -64,11 +64,12 @@ static ssize_t queue_requests_show(struct gendisk *disk= , char *page) static ssize_t queue_requests_store(struct gendisk *disk, const char *page, size_t count) { - unsigned long nr; - int ret, err; - unsigned int memflags; struct request_queue *q =3D disk->queue; struct blk_mq_tag_set *set =3D q->tag_set; + struct elevator_tags *et =3D NULL; + unsigned int memflags; + unsigned long nr; + int ret; =20 ret =3D queue_var_store(&nr, page, count); if (ret < 0) @@ -90,12 +91,18 @@ queue_requests_store(struct gendisk *disk, const char *= page, size_t count) goto unlock; } =20 + if (q->elevator && nr > q->elevator->et->nr_requests) { + /* allocate memory before freezing queue to prevent deadlock */ + et =3D blk_mq_alloc_sched_tags(set, q->nr_hw_queues, nr); + if (!et) { + ret =3D -ENOMEM; + goto unlock; + } + } + memflags =3D blk_mq_freeze_queue(q); mutex_lock(&q->elevator_lock); - err =3D blk_mq_update_nr_requests(disk->queue, nr); - if (err) - ret =3D err; - + blk_mq_update_nr_requests(disk->queue, et, nr); mutex_unlock(&q->elevator_lock); blk_mq_unfreeze_queue(q, memflags); =20 --=20 2.39.2 From nobody Sat Oct 4 14:36:15 2025 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) (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 C65672D0632; Fri, 15 Aug 2025 08:10:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.56 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755245414; cv=none; b=Sm8w0P1WDdS9/ZR3fiVSy4mj+FgRCS1loXIb14/i29HL4infd2+4ZgUlcTY5aycXJ72RdZozei7uD0cFQyrbTwdueBQvdbD2l6rW0SNwot1mWNdJdtweEsextA9lnXu5XT265GUh/HoeGlUd9Jfg9w8nQOUjKRoNcgoXzDRrHXY= ARC-Message-Signature: i=1; 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Fri, 15 Aug 2025 16:10:10 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP4 (Coremail) with SMTP id gCh0CgDHjxBc655o+xX_Dg--.53834S13; Fri, 15 Aug 2025 16:10:10 +0800 (CST) From: Yu Kuai To: axboe@kernel.dk, hare@suse.de, nilay@linux.ibm.com, ming.lei@redhat.com Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yukuai3@huawei.com, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com, johnny.chenyi@huawei.com Subject: [PATCH 09/10] blk-mq: remove blk_mq_tag_update_depth() Date: Fri, 15 Aug 2025 16:02:15 +0800 Message-Id: <20250815080216.410665-10-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20250815080216.410665-1-yukuai1@huaweicloud.com> References: <20250815080216.410665-1-yukuai1@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: gCh0CgDHjxBc655o+xX_Dg--.53834S13 X-Coremail-Antispam: 1UD129KBjvJXoW7Ar4xtF15Zr1xWF4rKF1DGFg_yoW8uFWfpF W3tanrK3yYqr1q9F4Dta9rAr1rKw4vgr18Ka9aq34Fqr1jkr4IqFn5Xr1kA3y0yrWkCF43 ArWqqryrJr1kJrDanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUmS14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF0E3s1l82xGYI kIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2 z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F 4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq 3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7 IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4U M4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2 kIc2xKxwCY1x0262kKe7AKxVWUtVW8ZwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkE bVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67 AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUCVW8JwCI 42IY6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF 4lIxAIcVC2z280aVAFwI0_Gr0_Cr1lIxAIcVC2z280aVCY1x0267AKxVW8Jr0_Cr1UYxBI daVFxhVjvjDU0xZFpf9x0JUQFxUUUUUU= X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ Content-Type: text/plain; charset="utf-8" From: Yu Kuai This helper is not used now. Signed-off-by: Yu Kuai --- block/blk-mq-tag.c | 31 ------------------------------- block/blk-mq.h | 2 -- 2 files changed, 33 deletions(-) diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index 84a452e708e4..cbb93a653cef 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -583,37 +583,6 @@ void blk_mq_free_tags(struct blk_mq_tags *tags) kfree(tags); } =20 -int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx, - struct blk_mq_tags **tagsptr, unsigned int tdepth) -{ - struct blk_mq_tags *tags =3D *tagsptr; - - /* - * If we are allowed to grow beyond the original size, allocate - * a new set of tags before freeing the old one. - */ - if (tdepth > tags->nr_tags) { - struct blk_mq_tag_set *set =3D hctx->queue->tag_set; - struct blk_mq_tags *new; - - new =3D blk_mq_alloc_map_and_rqs(set, hctx->queue_num, tdepth); - if (!new) - return -ENOMEM; - - blk_mq_free_map_and_rqs(set, *tagsptr, hctx->queue_num); - *tagsptr =3D new; - } else { - /* - * Don't need (or can't) update reserved tags here, they - * remain static and should never need resizing. - */ - sbitmap_queue_resize(&tags->bitmap_tags, - tdepth - tags->nr_reserved_tags); - } - - return 0; -} - void blk_mq_tag_resize_shared_tags(struct blk_mq_tag_set *set, unsigned in= t size) { struct blk_mq_tags *tags =3D set->shared_tags; diff --git a/block/blk-mq.h b/block/blk-mq.h index 98740f9c204e..aaa006fe5076 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -183,8 +183,6 @@ unsigned long blk_mq_get_tags(struct blk_mq_alloc_data = *data, int nr_tags, void blk_mq_put_tag(struct blk_mq_tags *tags, struct blk_mq_ctx *ctx, unsigned int tag); void blk_mq_put_tags(struct blk_mq_tags *tags, int *tag_array, int nr_tags= ); -int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx, - struct blk_mq_tags **tags, unsigned int depth); void blk_mq_tag_resize_shared_tags(struct blk_mq_tag_set *set, unsigned int size); void blk_mq_tag_update_sched_shared_tags(struct request_queue *q); --=20 2.39.2 From nobody Sat Oct 4 14:36:15 2025 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) (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 CE6BB2D47E9; 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dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTPS id 4c3FCR6dnszKHMlk; Fri, 15 Aug 2025 16:10:11 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id 3C3911A0F83; Fri, 15 Aug 2025 16:10:11 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP4 (Coremail) with SMTP id gCh0CgDHjxBc655o+xX_Dg--.53834S14; Fri, 15 Aug 2025 16:10:11 +0800 (CST) From: Yu Kuai To: axboe@kernel.dk, hare@suse.de, nilay@linux.ibm.com, ming.lei@redhat.com Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yukuai3@huawei.com, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com, johnny.chenyi@huawei.com Subject: [PATCH 10/10] blk-mq: fix stale nr_requests documentation Date: Fri, 15 Aug 2025 16:02:16 +0800 Message-Id: <20250815080216.410665-11-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20250815080216.410665-1-yukuai1@huaweicloud.com> References: <20250815080216.410665-1-yukuai1@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: gCh0CgDHjxBc655o+xX_Dg--.53834S14 X-Coremail-Antispam: 1UD129KBjvJXoW7KFWDCryfKr15Zw1xKFWfZrb_yoW8Xw1Dp3 yft39Fgwn5Zw18Wr10yay8tF13Aa95Aw43Jr4DKF1rtr98Awn29Fs2qr1rXF4xZrZ7AFWU urZ29r98Aa1qva7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUmS14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF0E3s1l82xGYI kIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2 z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F 4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq 3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7 IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4U M4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2 kIc2xKxwCY1x0262kKe7AKxVWUtVW8ZwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkE bVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67 AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVW8JVW5JwCI 42IY6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF 4lIxAIcVC2z280aVAFwI0_Gr0_Cr1lIxAIcVC2z280aVCY1x0267AKxVW8Jr0_Cr1UYxBI daVFxhVjvjDU0xZFpf9x0JUQFxUUUUUU= X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ Content-Type: text/plain; charset="utf-8" From: Yu Kuai The nr_requests documentation is still the removed single queue, remove it and update to current blk-mq. Signed-off-by: Yu Kuai --- Documentation/ABI/stable/sysfs-block | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-) diff --git a/Documentation/ABI/stable/sysfs-block b/Documentation/ABI/stabl= e/sysfs-block index 0ddffc9133d0..0ed10aeff86b 100644 --- a/Documentation/ABI/stable/sysfs-block +++ b/Documentation/ABI/stable/sysfs-block @@ -603,16 +603,10 @@ Date: July 2003 Contact: linux-block@vger.kernel.org Description: [RW] This controls how many requests may be allocated in the - block layer for read or write requests. Note that the total - allocated number may be twice this amount, since it applies only - to reads or writes (not the accumulated sum). - - To avoid priority inversion through request starvation, a - request queue maintains a separate request pool per each cgroup - when CONFIG_BLK_CGROUP is enabled, and this parameter applies to - each such per-block-cgroup request pool. IOW, if there are N - block cgroups, each request queue may have up to N request - pools, each independently regulated by nr_requests. + block layer. Noted this value only represents the quantity for a + single blk_mq_tags instance. The actual number for the entire + device depends on the hardware queue count, whether elevator is + enabled, and whether tags are shared. =20 =20 What: /sys/block//queue/nr_zones --=20 2.39.2