From patchwork Fri Apr 16 08:00:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 12206835 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1E526C433ED for ; Fri, 16 Apr 2021 08:00:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EEA4361166 for ; Fri, 16 Apr 2021 08:00:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237997AbhDPIBD (ORCPT ); Fri, 16 Apr 2021 04:01:03 -0400 Received: from out30-131.freemail.mail.aliyun.com ([115.124.30.131]:60985 "EHLO out30-131.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237986AbhDPIBD (ORCPT ); Fri, 16 Apr 2021 04:01:03 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R101e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04426;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=5;SR=0;TI=SMTPD_---0UVj6W0l_1618560037; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0UVj6W0l_1618560037) by smtp.aliyun-inc.com(127.0.0.1); Fri, 16 Apr 2021 16:00:37 +0800 From: Jeffle Xu To: ming.lei@redhat.com, snitzer@redhat.com, axboe@kernel.dk Cc: linux-block@vger.kernel.org, dm-devel@redhat.com Subject: [PATCH] block: introduce QUEUE_FLAG_POLL_CAP flag Date: Fri, 16 Apr 2021 16:00:37 +0800 Message-Id: <20210416080037.26335-1-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210401021927.343727-12-ming.lei@redhat.com> References: <20210401021927.343727-12-ming.lei@redhat.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Hi, How about this patch to remove the extra poll_capable() method? And the following 'dm: support IO polling for bio-based dm device' needs following change. ``` + /* + * Check for request-based device is remained to + * dm_mq_init_request_queue()->blk_mq_init_allocated_queue(). + * For bio-based device, only set QUEUE_FLAG_POLL when all underlying + * devices supporting polling. + */ + if (__table_type_bio_based(t->type)) { + if (dm_table_supports_poll(t)) { + blk_queue_flag_set(QUEUE_FLAG_POLL_CAP, q); + blk_queue_flag_set(QUEUE_FLAG_POLL, q); + } + else { + blk_queue_flag_clear(QUEUE_FLAG_POLL, q); + blk_queue_flag_clear(QUEUE_FLAG_POLL_CAP, q); + } + } ``` Introduce QUEUE_FLAG_POLL_CAP flag, indicating if the device supports IO polling or not. Thus both blk-mq and bio-based device could set this flag at the initialization phase, and then only this flag needs to be checked instead of rechecking if the device has the ability of IO polling when enabling IO polling via sysfs. For NVMe, the ability of IO polling may change after RESET, since nvme.poll_queues module parameter may change. Thus the ability of IO polling need to be rechecked after RESET. Signed-off-by: Jeffle Xu --- block/blk-mq.c | 5 +++-- block/blk-sysfs.c | 3 +-- drivers/nvme/host/core.c | 2 ++ include/linux/blk-mq.h | 12 ++++++++++++ include/linux/blkdev.h | 2 ++ 5 files changed, 20 insertions(+), 4 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 414f5d99d9de..55ef6b975169 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3227,9 +3227,10 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, q->tag_set = set; q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT; - if (set->nr_maps > HCTX_TYPE_POLL && - set->map[HCTX_TYPE_POLL].nr_queues) + if (blk_mq_poll_capable(set)) { + blk_queue_flag_set(QUEUE_FLAG_POLL_CAP, q); blk_queue_flag_set(QUEUE_FLAG_POLL, q); + } q->sg_reserved_size = INT_MAX; diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index db3268d41274..64f0ab84b606 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -426,8 +426,7 @@ static ssize_t queue_poll_store(struct request_queue *q, const char *page, unsigned long poll_on; ssize_t ret; - if (!q->tag_set || q->tag_set->nr_maps <= HCTX_TYPE_POLL || - !q->tag_set->map[HCTX_TYPE_POLL].nr_queues) + if(!blk_queue_poll_cap(q)) return -EINVAL; ret = queue_var_store(&poll_on, page, count); diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index bb7da34dd967..5344cc877b05 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -2210,6 +2210,8 @@ static int nvme_update_ns_info(struct nvme_ns *ns, struct nvme_id_ns *id) ns->lba_shift = id->lbaf[lbaf].ds; nvme_set_queue_limits(ns->ctrl, ns->queue); + blk_mq_check_poll(ns->disk->queue, ns->disk->queue->tag_set); + ret = nvme_configure_metadata(ns, id); if (ret) goto out_unfreeze; diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 2c473c9b8990..ee4c89c8bebc 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -618,4 +618,16 @@ blk_qc_t blk_mq_submit_bio(struct bio *bio); void blk_mq_hctx_set_fq_lock_class(struct blk_mq_hw_ctx *hctx, struct lock_class_key *key); +static inline bool blk_mq_poll_capable(struct blk_mq_tag_set *set) +{ + return set->nr_maps > HCTX_TYPE_POLL && + set->map[HCTX_TYPE_POLL].nr_queues; +} + +static inline void blk_mq_check_poll(struct request_queue *q, + struct blk_mq_tag_set *set) +{ + if (blk_mq_poll_capable(set)) + blk_queue_flag_set(QUEUE_FLAG_POLL_CAP, q); +} #endif diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 1e88116dc070..d192a106bf40 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -621,6 +621,7 @@ struct request_queue { #define QUEUE_FLAG_RQ_ALLOC_TIME 27 /* record rq->alloc_time_ns */ #define QUEUE_FLAG_HCTX_ACTIVE 28 /* at least one blk-mq hctx is active */ #define QUEUE_FLAG_NOWAIT 29 /* device supports NOWAIT */ +#define QUEUE_FLAG_POLL_CAP 30 /* device supports IO polling */ #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ (1 << QUEUE_FLAG_SAME_COMP) | \ @@ -668,6 +669,7 @@ bool blk_queue_flag_test_and_set(unsigned int flag, struct request_queue *q); #define blk_queue_registered(q) test_bit(QUEUE_FLAG_REGISTERED, &(q)->queue_flags) #define blk_queue_nowait(q) test_bit(QUEUE_FLAG_NOWAIT, &(q)->queue_flags) #define blk_queue_poll(q) test_bit(QUEUE_FLAG_POLL, &(q)->queue_flags) +#define blk_queue_poll_cap(q) test_bit(QUEUE_FLAG_POLL_CAP, &(q)->queue_flags) extern void blk_set_pm_only(struct request_queue *q); extern void blk_clear_pm_only(struct request_queue *q);