From patchwork Wed Mar 3 11:57:29 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 12113867 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=-16.8 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 99021C433E0 for ; Wed, 3 Mar 2021 16:42:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4C016614A7 for ; Wed, 3 Mar 2021 16:42:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346755AbhCCQip (ORCPT ); Wed, 3 Mar 2021 11:38:45 -0500 Received: from out30-131.freemail.mail.aliyun.com ([115.124.30.131]:35497 "EHLO out30-131.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1442100AbhCCL60 (ORCPT ); Wed, 3 Mar 2021 06:58:26 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R121e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=alimailimapcm10staff010182156082;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0UQGMHlb_1614772661; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0UQGMHlb_1614772661) by smtp.aliyun-inc.com(127.0.0.1); Wed, 03 Mar 2021 19:57:41 +0800 From: Jeffle Xu To: msnitzer@redhat.com, axboe@kernel.dk Cc: io-uring@vger.kernel.org, dm-devel@redhat.com, linux-block@vger.kernel.org, mpatocka@redhat.com, caspar@linux.alibaba.com, joseph.qi@linux.alibaba.com Subject: [PATCH v5 01/12] block: move definition of blk_qc_t to types.h Date: Wed, 3 Mar 2021 19:57:29 +0800 Message-Id: <20210303115740.127001-2-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210303115740.127001-1-jefflexu@linux.alibaba.com> References: <20210303115740.127001-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org So that kiocb.ki_cookie can be defined as blk_qc_t, which will enforce the encapsulation. Signed-off-by: Jeffle Xu Reviewed-by: Christoph Hellwig Reviewed-by: Mike Snitzer --- include/linux/blk_types.h | 2 +- include/linux/fs.h | 2 +- include/linux/types.h | 3 +++ 3 files changed, 5 insertions(+), 2 deletions(-) diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index db026b6ec15a..fb429daaa909 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -505,7 +505,7 @@ static inline int op_stat_group(unsigned int op) return op_is_write(op); } -typedef unsigned int blk_qc_t; +/* Macros for blk_qc_t */ #define BLK_QC_T_NONE -1U #define BLK_QC_T_SHIFT 16 #define BLK_QC_T_INTERNAL (1U << 31) diff --git a/include/linux/fs.h b/include/linux/fs.h index ec8f3ddf4a6a..8b14dacf618d 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -332,7 +332,7 @@ struct kiocb { u16 ki_hint; u16 ki_ioprio; /* See linux/ioprio.h */ union { - unsigned int ki_cookie; /* for ->iopoll */ + blk_qc_t ki_cookie; /* for ->iopoll */ struct wait_page_queue *ki_waitq; /* for async buffered IO */ }; diff --git a/include/linux/types.h b/include/linux/types.h index ac825ad90e44..52a54ed6ffac 100644 --- a/include/linux/types.h +++ b/include/linux/types.h @@ -125,6 +125,9 @@ typedef s64 int64_t; typedef u64 sector_t; typedef u64 blkcnt_t; +/* cookie used for IO polling */ +typedef unsigned int blk_qc_t; + /* * The type of an index into the pagecache. */ From patchwork Wed Mar 3 11:57:30 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 12113871 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=-16.8 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 C3175C433E9 for ; Wed, 3 Mar 2021 16:42:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9248964E6F for ; Wed, 3 Mar 2021 16:42:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346798AbhCCQiu (ORCPT ); Wed, 3 Mar 2021 11:38:50 -0500 Received: from out30-132.freemail.mail.aliyun.com ([115.124.30.132]:48743 "EHLO out30-132.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1442099AbhCCL62 (ORCPT ); Wed, 3 Mar 2021 06:58:28 -0500 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=e01e04423;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0UQFn1HQ_1614772662; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0UQFn1HQ_1614772662) by smtp.aliyun-inc.com(127.0.0.1); Wed, 03 Mar 2021 19:57:43 +0800 From: Jeffle Xu To: msnitzer@redhat.com, axboe@kernel.dk Cc: io-uring@vger.kernel.org, dm-devel@redhat.com, linux-block@vger.kernel.org, mpatocka@redhat.com, caspar@linux.alibaba.com, joseph.qi@linux.alibaba.com Subject: [PATCH v5 02/12] block: add queue_to_disk() to get gendisk from request_queue Date: Wed, 3 Mar 2021 19:57:30 +0800 Message-Id: <20210303115740.127001-3-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210303115740.127001-1-jefflexu@linux.alibaba.com> References: <20210303115740.127001-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Sometimes we need to get the corresponding gendisk from request_queue. It is preferred that block drivers store private data in gendisk->private_data rather than request_queue->queuedata, e.g. see: commit c4a59c4e5db3 ("dm: stop using ->queuedata"). So if only request_queue is given, we need to get its corresponding gendisk to get the private data stored in that gendisk. Signed-off-by: Jeffle Xu Reviewed-by: Mike Snitzer --- include/linux/blkdev.h | 2 ++ include/trace/events/kyber.h | 6 +++--- 2 files changed, 5 insertions(+), 3 deletions(-) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index c032cfe133c7..b81a9fe015ab 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -687,6 +687,8 @@ static inline bool blk_account_rq(struct request *rq) dma_map_page_attrs(dev, (bv)->bv_page, (bv)->bv_offset, (bv)->bv_len, \ (dir), (attrs)) +#define queue_to_disk(q) (dev_to_disk(kobj_to_dev((q)->kobj.parent))) + static inline bool queue_is_mq(struct request_queue *q) { return q->mq_ops; diff --git a/include/trace/events/kyber.h b/include/trace/events/kyber.h index c0e7d24ca256..f9802562edf6 100644 --- a/include/trace/events/kyber.h +++ b/include/trace/events/kyber.h @@ -30,7 +30,7 @@ TRACE_EVENT(kyber_latency, ), TP_fast_assign( - __entry->dev = disk_devt(dev_to_disk(kobj_to_dev(q->kobj.parent))); + __entry->dev = disk_devt(queue_to_disk(q)); strlcpy(__entry->domain, domain, sizeof(__entry->domain)); strlcpy(__entry->type, type, sizeof(__entry->type)); __entry->percentile = percentile; @@ -59,7 +59,7 @@ TRACE_EVENT(kyber_adjust, ), TP_fast_assign( - __entry->dev = disk_devt(dev_to_disk(kobj_to_dev(q->kobj.parent))); + __entry->dev = disk_devt(queue_to_disk(q)); strlcpy(__entry->domain, domain, sizeof(__entry->domain)); __entry->depth = depth; ), @@ -81,7 +81,7 @@ TRACE_EVENT(kyber_throttled, ), TP_fast_assign( - __entry->dev = disk_devt(dev_to_disk(kobj_to_dev(q->kobj.parent))); + __entry->dev = disk_devt(queue_to_disk(q)); strlcpy(__entry->domain, domain, sizeof(__entry->domain)); ), From patchwork Wed Mar 3 11:57:31 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 12113873 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=-16.8 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 C543CC433DB for ; Wed, 3 Mar 2021 16:42:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6C5C864EBB for ; Wed, 3 Mar 2021 16:42:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346674AbhCCQix (ORCPT ); Wed, 3 Mar 2021 11:38:53 -0500 Received: from out30-56.freemail.mail.aliyun.com ([115.124.30.56]:55579 "EHLO out30-56.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1442101AbhCCL63 (ORCPT ); Wed, 3 Mar 2021 06:58:29 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R201e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04420;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0UQFBO8U_1614772663; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0UQFBO8U_1614772663) by smtp.aliyun-inc.com(127.0.0.1); Wed, 03 Mar 2021 19:57:44 +0800 From: Jeffle Xu To: msnitzer@redhat.com, axboe@kernel.dk Cc: io-uring@vger.kernel.org, dm-devel@redhat.com, linux-block@vger.kernel.org, mpatocka@redhat.com, caspar@linux.alibaba.com, joseph.qi@linux.alibaba.com Subject: [PATCH v5 03/12] block: add poll method to support bio-based IO polling Date: Wed, 3 Mar 2021 19:57:31 +0800 Message-Id: <20210303115740.127001-4-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210303115740.127001-1-jefflexu@linux.alibaba.com> References: <20210303115740.127001-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org ->poll_fn was introduced in commit ea435e1b9392 ("block: add a poll_fn callback to struct request_queue") to support bio-based queues such as nvme multipath, but was later removed in commit 529262d56dbe ("block: remove ->poll_fn"). Given commit c62b37d96b6e ("block: move ->make_request_fn to struct block_device_operations") restore the possibility of bio-based IO polling support by adding an ->poll method to gendisk->fops. Make blk_mq_poll() specific to blk-mq, while blk_bio_poll() is originally a copy from blk_mq_poll(), and is specific to bio-based polling. Currently hybrid polling is not supported by bio-based polling. Signed-off-by: Jeffle Xu Reviewed-by: Mike Snitzer --- block/blk-core.c | 58 ++++++++++++++++++++++++++++++++++++++++++ block/blk-mq.c | 22 +--------------- include/linux/blk-mq.h | 1 + include/linux/blkdev.h | 1 + 4 files changed, 61 insertions(+), 21 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index fc60ff208497..6d7d53030d7c 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1119,6 +1119,64 @@ blk_qc_t submit_bio(struct bio *bio) } EXPORT_SYMBOL(submit_bio); + +static int blk_bio_poll(struct request_queue *q, blk_qc_t cookie, bool spin) +{ + long state; + struct gendisk *disk = queue_to_disk(q); + + state = current->state; + do { + int ret; + + ret = disk->fops->poll(q, cookie); + if (ret > 0) { + __set_current_state(TASK_RUNNING); + return ret; + } + + if (signal_pending_state(state, current)) + __set_current_state(TASK_RUNNING); + + if (current->state == TASK_RUNNING) + return 1; + if (ret < 0 || !spin) + break; + cpu_relax(); + } while (!need_resched()); + + __set_current_state(TASK_RUNNING); + return 0; +} + +/** + * blk_poll - poll for IO completions + * @q: the queue + * @cookie: cookie passed back at IO submission time + * @spin: whether to spin for completions + * + * Description: + * Poll for completions on the passed in queue. Returns number of + * completed entries found. If @spin is true, then blk_poll will continue + * looping until at least one completion is found, unless the task is + * otherwise marked running (or we need to reschedule). + */ +int blk_poll(struct request_queue *q, blk_qc_t cookie, bool spin) +{ + if (!blk_qc_t_valid(cookie) || + !test_bit(QUEUE_FLAG_POLL, &q->queue_flags)) + return 0; + + if (current->plug) + blk_flush_plug_list(current->plug, false); + + if (queue_is_mq(q)) + return blk_mq_poll(q, cookie, spin); + else + return blk_bio_poll(q, cookie, spin); +} +EXPORT_SYMBOL_GPL(blk_poll); + /** * blk_cloned_rq_check_limits - Helper function to check a cloned request * for the new queue limits diff --git a/block/blk-mq.c b/block/blk-mq.c index d4d7c1caa439..214fa30b460a 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3852,30 +3852,11 @@ static bool blk_mq_poll_hybrid(struct request_queue *q, return blk_mq_poll_hybrid_sleep(q, rq); } -/** - * blk_poll - poll for IO completions - * @q: the queue - * @cookie: cookie passed back at IO submission time - * @spin: whether to spin for completions - * - * Description: - * Poll for completions on the passed in queue. Returns number of - * completed entries found. If @spin is true, then blk_poll will continue - * looping until at least one completion is found, unless the task is - * otherwise marked running (or we need to reschedule). - */ -int blk_poll(struct request_queue *q, blk_qc_t cookie, bool spin) +int blk_mq_poll(struct request_queue *q, blk_qc_t cookie, bool spin) { struct blk_mq_hw_ctx *hctx; long state; - if (!blk_qc_t_valid(cookie) || - !test_bit(QUEUE_FLAG_POLL, &q->queue_flags)) - return 0; - - if (current->plug) - blk_flush_plug_list(current->plug, false); - hctx = q->queue_hw_ctx[blk_qc_t_to_queue_num(cookie)]; /* @@ -3917,7 +3898,6 @@ int blk_poll(struct request_queue *q, blk_qc_t cookie, bool spin) __set_current_state(TASK_RUNNING); return 0; } -EXPORT_SYMBOL_GPL(blk_poll); unsigned int blk_mq_rq_cpu(struct request *rq) { diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 2c473c9b8990..6a7b693b9917 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -615,6 +615,7 @@ static inline void blk_rq_bio_prep(struct request *rq, struct bio *bio, } blk_qc_t blk_mq_submit_bio(struct bio *bio); +int blk_mq_poll(struct request_queue *q, blk_qc_t cookie, bool spin); void blk_mq_hctx_set_fq_lock_class(struct blk_mq_hw_ctx *hctx, struct lock_class_key *key); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index b81a9fe015ab..9dc83c30e7bc 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1866,6 +1866,7 @@ static inline void blk_ksm_unregister(struct request_queue *q) { } struct block_device_operations { blk_qc_t (*submit_bio) (struct bio *bio); + int (*poll)(struct request_queue *q, blk_qc_t cookie); int (*open) (struct block_device *, fmode_t); void (*release) (struct gendisk *, fmode_t); int (*rw_page)(struct block_device *, sector_t, struct page *, unsigned int); From patchwork Wed Mar 3 11:57:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 12113875 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=-16.8 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 DE306C433E0 for ; Wed, 3 Mar 2021 16:42:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 942E364E6F for ; Wed, 3 Mar 2021 16:42:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346831AbhCCQiy (ORCPT ); Wed, 3 Mar 2021 11:38:54 -0500 Received: from out30-54.freemail.mail.aliyun.com ([115.124.30.54]:57298 "EHLO out30-54.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1442103AbhCCL6a (ORCPT ); Wed, 3 Mar 2021 06:58:30 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R131e4;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=8;SR=0;TI=SMTPD_---0UQGHkBm_1614772664; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0UQGHkBm_1614772664) by smtp.aliyun-inc.com(127.0.0.1); Wed, 03 Mar 2021 19:57:45 +0800 From: Jeffle Xu To: msnitzer@redhat.com, axboe@kernel.dk Cc: io-uring@vger.kernel.org, dm-devel@redhat.com, linux-block@vger.kernel.org, mpatocka@redhat.com, caspar@linux.alibaba.com, joseph.qi@linux.alibaba.com Subject: [PATCH v5 04/12] block: add poll_capable method to support bio-based IO polling Date: Wed, 3 Mar 2021 19:57:32 +0800 Message-Id: <20210303115740.127001-5-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210303115740.127001-1-jefflexu@linux.alibaba.com> References: <20210303115740.127001-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org This method can be used to check if bio-based device supports IO polling or not. For mq devices, checking for hw queue in polling mode is adequate, while the sanity check shall be implementation specific for bio-based devices. For example, dm device needs to check if all underlying devices are capable of IO polling. Though bio-based device may have done the sanity check during the device initialization phase, cacheing the result of this sanity check (such as by cacheing in the queue_flags) may not work. Because for dm devices, users could change the state of the underlying devices through '/sys/block//io_poll', bypassing the dm device above. In this case, the cached result of the very beginning sanity check could be out-of-date. Thus the sanity check needs to be done every time 'io_poll' is to be modified. Signed-off-by: Jeffle Xu --- block/blk-sysfs.c | 14 +++++++++++--- include/linux/blkdev.h | 1 + 2 files changed, 12 insertions(+), 3 deletions(-) diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 0f4f0c8a7825..367c1d9a55c6 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -426,9 +426,17 @@ 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) - return -EINVAL; + if (queue_is_mq(q)) { + if (!q->tag_set || q->tag_set->nr_maps <= HCTX_TYPE_POLL || + !q->tag_set->map[HCTX_TYPE_POLL].nr_queues) + return -EINVAL; + } else { + struct gendisk *disk = queue_to_disk(q); + + if (!disk->fops->poll_capable || + !disk->fops->poll_capable(disk)) + return -EINVAL; + } ret = queue_var_store(&poll_on, page, count); if (ret < 0) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 9dc83c30e7bc..7df40792c032 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1867,6 +1867,7 @@ static inline void blk_ksm_unregister(struct request_queue *q) { } struct block_device_operations { blk_qc_t (*submit_bio) (struct bio *bio); int (*poll)(struct request_queue *q, blk_qc_t cookie); + bool (*poll_capable)(struct gendisk *disk); int (*open) (struct block_device *, fmode_t); void (*release) (struct gendisk *, fmode_t); int (*rw_page)(struct block_device *, sector_t, struct page *, unsigned int); From patchwork Wed Mar 3 11:57:33 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 12113887 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=-16.8 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 16132C4332B for ; Wed, 3 Mar 2021 16:43:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DD14A64EBB for ; Wed, 3 Mar 2021 16:43:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346930AbhCCQjM (ORCPT ); Wed, 3 Mar 2021 11:39:12 -0500 Received: from out30-54.freemail.mail.aliyun.com ([115.124.30.54]:40943 "EHLO out30-54.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1442117AbhCCL6k (ORCPT ); Wed, 3 Mar 2021 06:58:40 -0500 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=8;SR=0;TI=SMTPD_---0UQGMHmS_1614772665; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0UQGMHmS_1614772665) by smtp.aliyun-inc.com(127.0.0.1); Wed, 03 Mar 2021 19:57:46 +0800 From: Jeffle Xu To: msnitzer@redhat.com, axboe@kernel.dk Cc: io-uring@vger.kernel.org, dm-devel@redhat.com, linux-block@vger.kernel.org, mpatocka@redhat.com, caspar@linux.alibaba.com, joseph.qi@linux.alibaba.com Subject: [PATCH v5 05/12] blk-mq: extract one helper function polling hw queue Date: Wed, 3 Mar 2021 19:57:33 +0800 Message-Id: <20210303115740.127001-6-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210303115740.127001-1-jefflexu@linux.alibaba.com> References: <20210303115740.127001-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Extract the logic of polling one hw queue and related statistics handling out as the helper function. Signed-off-by: Jeffle Xu --- block/blk-mq.c | 5 +---- include/linux/blk-mq.h | 13 +++++++++++++ 2 files changed, 14 insertions(+), 4 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 214fa30b460a..6ef9f0b038c2 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3876,11 +3876,8 @@ int blk_mq_poll(struct request_queue *q, blk_qc_t cookie, bool spin) do { int ret; - hctx->poll_invoked++; - - ret = q->mq_ops->poll(hctx); + ret = blk_mq_poll_hctx(q, hctx); if (ret > 0) { - hctx->poll_success++; __set_current_state(TASK_RUNNING); return ret; } diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 6a7b693b9917..b406cab347d6 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -614,6 +614,19 @@ static inline void blk_rq_bio_prep(struct request *rq, struct bio *bio, rq->rq_disk = bio->bi_bdev->bd_disk; } +static inline int blk_mq_poll_hctx(struct request_queue *q, + struct blk_mq_hw_ctx *hctx) +{ + int ret; + + hctx->poll_invoked++; + ret = q->mq_ops->poll(hctx); + if (ret > 0) + hctx->poll_success++; + + return ret; +} + blk_qc_t blk_mq_submit_bio(struct bio *bio); int blk_mq_poll(struct request_queue *q, blk_qc_t cookie, bool spin); void blk_mq_hctx_set_fq_lock_class(struct blk_mq_hw_ctx *hctx, From patchwork Wed Mar 3 11:57:34 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 12113889 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=-16.8 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 44A9CC433DB for ; Wed, 3 Mar 2021 16:43:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0655964E74 for ; Wed, 3 Mar 2021 16:43:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346970AbhCCQjQ (ORCPT ); Wed, 3 Mar 2021 11:39:16 -0500 Received: from out30-133.freemail.mail.aliyun.com ([115.124.30.133]:37438 "EHLO out30-133.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1442109AbhCCL6n (ORCPT ); Wed, 3 Mar 2021 06:58:43 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R121e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04420;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0UQFn1I4_1614772666; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0UQFn1I4_1614772666) by smtp.aliyun-inc.com(127.0.0.1); Wed, 03 Mar 2021 19:57:47 +0800 From: Jeffle Xu To: msnitzer@redhat.com, axboe@kernel.dk Cc: io-uring@vger.kernel.org, dm-devel@redhat.com, linux-block@vger.kernel.org, mpatocka@redhat.com, caspar@linux.alibaba.com, joseph.qi@linux.alibaba.com Subject: [PATCH v5 06/12] blk-mq: add iterator for polling hw queues Date: Wed, 3 Mar 2021 19:57:34 +0800 Message-Id: <20210303115740.127001-7-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210303115740.127001-1-jefflexu@linux.alibaba.com> References: <20210303115740.127001-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Add one helper function for iterating all hardware queues in polling mode. Signed-off-by: Jeffle Xu --- include/linux/blk-mq.h | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index b406cab347d6..d22269b3dbe9 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -582,6 +582,13 @@ static inline void *blk_mq_rq_to_pdu(struct request *rq) for ((i) = 0; (i) < (q)->nr_hw_queues && \ ({ hctx = (q)->queue_hw_ctx[i]; 1; }); (i)++) +#define queue_for_each_poll_hw_ctx(q, hctx, i) \ + for ((i) = 0; ((q)->tag_set->nr_maps > HCTX_TYPE_POLL) && \ + (i) < (q)->tag_set->map[HCTX_TYPE_POLL].nr_queues && \ + ({ int __idx = (q)->tag_set->map[HCTX_TYPE_POLL].queue_offset + (i); \ + hctx = (q)->queue_hw_ctx[__idx]; 1; }); \ + (i)++) + #define hctx_for_each_ctx(hctx, ctx, i) \ for ((i) = 0; (i) < (hctx)->nr_ctx && \ ({ ctx = (hctx)->ctxs[(i)]; 1; }); (i)++) From patchwork Wed Mar 3 11:57:35 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 12113877 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=-16.8 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 6F6C3C433DB for ; Wed, 3 Mar 2021 16:43:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3D99B64EBB for ; Wed, 3 Mar 2021 16:43:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346822AbhCCQi4 (ORCPT ); Wed, 3 Mar 2021 11:38:56 -0500 Received: from out30-54.freemail.mail.aliyun.com ([115.124.30.54]:48176 "EHLO out30-54.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1442110AbhCCL6d (ORCPT ); Wed, 3 Mar 2021 06:58:33 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R211e4;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=8;SR=0;TI=SMTPD_---0UQFn1IH_1614772667; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0UQFn1IH_1614772667) by smtp.aliyun-inc.com(127.0.0.1); Wed, 03 Mar 2021 19:57:48 +0800 From: Jeffle Xu To: msnitzer@redhat.com, axboe@kernel.dk Cc: io-uring@vger.kernel.org, dm-devel@redhat.com, linux-block@vger.kernel.org, mpatocka@redhat.com, caspar@linux.alibaba.com, joseph.qi@linux.alibaba.com Subject: [PATCH v5 07/12] blk-mq: add one helper function getting hw queue Date: Wed, 3 Mar 2021 19:57:35 +0800 Message-Id: <20210303115740.127001-8-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210303115740.127001-1-jefflexu@linux.alibaba.com> References: <20210303115740.127001-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Add one helper function getting hw queue mapping to specific CPU, and of specific type. Signed-off-by: Jeffle Xu --- block/blk-mq.c | 10 ++++++++++ include/linux/blk-mq.h | 2 ++ 2 files changed, 12 insertions(+) diff --git a/block/blk-mq.c b/block/blk-mq.c index 6ef9f0b038c2..72390f208c82 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3902,6 +3902,16 @@ unsigned int blk_mq_rq_cpu(struct request *rq) } EXPORT_SYMBOL(blk_mq_rq_cpu); + +struct blk_mq_hw_ctx *blk_mq_get_hctx(struct request_queue *q, int cpu, + unsigned int flags) +{ + struct blk_mq_ctx *ctx = __blk_mq_get_ctx(q, cpu); + + return blk_mq_map_queue(q, flags, ctx); +} +EXPORT_SYMBOL(blk_mq_get_hctx); + static int __init blk_mq_init(void) { int i; diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index d22269b3dbe9..149f6a9d9aa7 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -638,5 +638,7 @@ blk_qc_t blk_mq_submit_bio(struct bio *bio); int blk_mq_poll(struct request_queue *q, blk_qc_t cookie, bool spin); void blk_mq_hctx_set_fq_lock_class(struct blk_mq_hw_ctx *hctx, struct lock_class_key *key); +struct blk_mq_hw_ctx *blk_mq_get_hctx(struct request_queue *q, int cpu, + unsigned int flags); #endif From patchwork Wed Mar 3 11:57:36 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 12113891 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=-16.8 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 B13D1C433E0 for ; Wed, 3 Mar 2021 16:43:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7346C64EBB for ; Wed, 3 Mar 2021 16:43:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347023AbhCCQjS (ORCPT ); Wed, 3 Mar 2021 11:39:18 -0500 Received: from out30-130.freemail.mail.aliyun.com ([115.124.30.130]:52275 "EHLO out30-130.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1442134AbhCCL67 (ORCPT ); Wed, 3 Mar 2021 06:58:59 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R411e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04423;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0UQFCWmG_1614772668; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0UQFCWmG_1614772668) by smtp.aliyun-inc.com(127.0.0.1); Wed, 03 Mar 2021 19:57:49 +0800 From: Jeffle Xu To: msnitzer@redhat.com, axboe@kernel.dk Cc: io-uring@vger.kernel.org, dm-devel@redhat.com, linux-block@vger.kernel.org, mpatocka@redhat.com, caspar@linux.alibaba.com, joseph.qi@linux.alibaba.com Subject: [PATCH v5 08/12] dm: always return BLK_QC_T_NONE for bio-based device Date: Wed, 3 Mar 2021 19:57:36 +0800 Message-Id: <20210303115740.127001-9-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210303115740.127001-1-jefflexu@linux.alibaba.com> References: <20210303115740.127001-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Currently the returned cookie of bio-based device is not used at all. Cookie of bio-based device will be refactored in the following patch. Signed-off-by: Jeffle Xu Reviewed-by: Mike Snitzer --- drivers/md/dm.c | 26 ++++++++++---------------- 1 file changed, 10 insertions(+), 16 deletions(-) diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 50b693d776d6..f1b76203b3c7 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1294,14 +1294,13 @@ static noinline void __set_swap_bios_limit(struct mapped_device *md, int latch) mutex_unlock(&md->swap_bios_lock); } -static blk_qc_t __map_bio(struct dm_target_io *tio) +static void __map_bio(struct dm_target_io *tio) { int r; sector_t sector; struct bio *clone = &tio->clone; struct dm_io *io = tio->io; struct dm_target *ti = tio->ti; - blk_qc_t ret = BLK_QC_T_NONE; clone->bi_end_io = clone_endio; @@ -1328,7 +1327,7 @@ static blk_qc_t __map_bio(struct dm_target_io *tio) case DM_MAPIO_REMAPPED: /* the bio has been remapped so dispatch it */ trace_block_bio_remap(clone, bio_dev(io->orig_bio), sector); - ret = submit_bio_noacct(clone); + submit_bio_noacct(clone); break; case DM_MAPIO_KILL: if (unlikely(swap_bios_limit(ti, clone))) { @@ -1350,8 +1349,6 @@ static blk_qc_t __map_bio(struct dm_target_io *tio) DMWARN("unimplemented target map return value: %d", r); BUG(); } - - return ret; } static void bio_setup_sector(struct bio *bio, sector_t sector, unsigned len) @@ -1438,7 +1435,7 @@ static void alloc_multiple_bios(struct bio_list *blist, struct clone_info *ci, } } -static blk_qc_t __clone_and_map_simple_bio(struct clone_info *ci, +static void __clone_and_map_simple_bio(struct clone_info *ci, struct dm_target_io *tio, unsigned *len) { struct bio *clone = &tio->clone; @@ -1449,7 +1446,7 @@ static blk_qc_t __clone_and_map_simple_bio(struct clone_info *ci, if (len) bio_setup_sector(clone, ci->sector, *len); - return __map_bio(tio); + __map_bio(tio); } static void __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti, @@ -1463,7 +1460,7 @@ static void __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti, while ((bio = bio_list_pop(&blist))) { tio = container_of(bio, struct dm_target_io, clone); - (void) __clone_and_map_simple_bio(ci, tio, len); + __clone_and_map_simple_bio(ci, tio, len); } } @@ -1507,7 +1504,7 @@ static int __clone_and_map_data_bio(struct clone_info *ci, struct dm_target *ti, free_tio(tio); return r; } - (void) __map_bio(tio); + __map_bio(tio); return 0; } @@ -1622,11 +1619,10 @@ static void init_clone_info(struct clone_info *ci, struct mapped_device *md, /* * Entry point to split a bio into clones and submit them to the targets. */ -static blk_qc_t __split_and_process_bio(struct mapped_device *md, +static void __split_and_process_bio(struct mapped_device *md, struct dm_table *map, struct bio *bio) { struct clone_info ci; - blk_qc_t ret = BLK_QC_T_NONE; int error = 0; init_clone_info(&ci, md, map, bio); @@ -1670,7 +1666,7 @@ static blk_qc_t __split_and_process_bio(struct mapped_device *md, bio_chain(b, bio); trace_block_split(b, bio->bi_iter.bi_sector); - ret = submit_bio_noacct(bio); + submit_bio_noacct(bio); break; } } @@ -1678,13 +1674,11 @@ static blk_qc_t __split_and_process_bio(struct mapped_device *md, /* drop the extra reference count */ dec_pending(ci.io, errno_to_blk_status(error)); - return ret; } static blk_qc_t dm_submit_bio(struct bio *bio) { struct mapped_device *md = bio->bi_bdev->bd_disk->private_data; - blk_qc_t ret = BLK_QC_T_NONE; int srcu_idx; struct dm_table *map; @@ -1714,10 +1708,10 @@ static blk_qc_t dm_submit_bio(struct bio *bio) if (is_abnormal_io(bio)) blk_queue_split(&bio); - ret = __split_and_process_bio(md, map, bio); + __split_and_process_bio(md, map, bio); out: dm_put_live_table(md, srcu_idx); - return ret; + return BLK_QC_T_NONE; } /*----------------------------------------------------------------- From patchwork Wed Mar 3 11:57:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 12113879 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=-16.8 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 5330DC433E0 for ; Wed, 3 Mar 2021 16:43:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1AEBE614A7 for ; Wed, 3 Mar 2021 16:43:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346861AbhCCQjA (ORCPT ); Wed, 3 Mar 2021 11:39:00 -0500 Received: from out30-42.freemail.mail.aliyun.com ([115.124.30.42]:35837 "EHLO out30-42.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1442186AbhCCL6e (ORCPT ); Wed, 3 Mar 2021 06:58:34 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R331e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04400;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0UQFBO9Y_1614772670; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0UQFBO9Y_1614772670) by smtp.aliyun-inc.com(127.0.0.1); Wed, 03 Mar 2021 19:57:50 +0800 From: Jeffle Xu To: msnitzer@redhat.com, axboe@kernel.dk Cc: io-uring@vger.kernel.org, dm-devel@redhat.com, linux-block@vger.kernel.org, mpatocka@redhat.com, caspar@linux.alibaba.com, joseph.qi@linux.alibaba.com Subject: [PATCH v5 09/12] nvme/pci: don't wait for locked polling queue Date: Wed, 3 Mar 2021 19:57:37 +0800 Message-Id: <20210303115740.127001-10-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210303115740.127001-1-jefflexu@linux.alibaba.com> References: <20210303115740.127001-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org There's no sense waiting for the hw queue when it currently has been locked by another polling instance. The polling instance currently occupying the hw queue will help reap the completion events. It shall be safe to surrender the hw queue, as long as we could reapply for polling later. For Synchronous polling, blk_poll() will reapply for polling, since @spin is always True in this case. While For asynchronous polling, i.e. io_uring itself will reapply for polling when the previous polling returns 0. Besides, it shall do no harm to the polling performance of mq devices. Signed-off-by: Jeffle Xu --- drivers/nvme/host/pci.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 38b0d694dfc9..150e56ed6d15 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -1106,7 +1106,9 @@ static int nvme_poll(struct blk_mq_hw_ctx *hctx) if (!nvme_cqe_pending(nvmeq)) return 0; - spin_lock(&nvmeq->cq_poll_lock); + if (!spin_trylock(&nvmeq->cq_poll_lock)) + return 0; + found = nvme_process_cq(nvmeq); spin_unlock(&nvmeq->cq_poll_lock); From patchwork Wed Mar 3 11:57:38 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 12113881 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=-16.8 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 EB78AC43381 for ; Wed, 3 Mar 2021 16:43:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C0E3A64E6F for ; Wed, 3 Mar 2021 16:43:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346898AbhCCQjL (ORCPT ); Wed, 3 Mar 2021 11:39:11 -0500 Received: from out30-45.freemail.mail.aliyun.com ([115.124.30.45]:52924 "EHLO out30-45.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1442240AbhCCL6j (ORCPT ); Wed, 3 Mar 2021 06:58:39 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R451e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e01424;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0UQG29rb_1614772671; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0UQG29rb_1614772671) by smtp.aliyun-inc.com(127.0.0.1); Wed, 03 Mar 2021 19:57:51 +0800 From: Jeffle Xu To: msnitzer@redhat.com, axboe@kernel.dk Cc: io-uring@vger.kernel.org, dm-devel@redhat.com, linux-block@vger.kernel.org, mpatocka@redhat.com, caspar@linux.alibaba.com, joseph.qi@linux.alibaba.com Subject: [PATCH v5 10/12] block: fastpath for bio-based polling Date: Wed, 3 Mar 2021 19:57:38 +0800 Message-Id: <20210303115740.127001-11-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210303115740.127001-1-jefflexu@linux.alibaba.com> References: <20210303115740.127001-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Offer one fastpath for bio-based polling when bio submitted to dm device is not split. In this case, there will be only one bio submitted to only one polling hw queue of one underlying mq device, and thus we don't need to track all split bios or iterate through all polling hw queues. The pointer to the polling hw queue the bio submitted to is returned here as the returned cookie. In this case, the polling routine will call mq_ops->poll() directly with the hw queue converted from the input cookie. If the original bio submitted to dm device is split to multiple bios and thus submitted to multiple polling hw queues, the polling routine will fall back to iterating all hw queues (in polling mode) of all underlying mq devices. Signed-off-by: Jeffle Xu --- block/blk-core.c | 73 +++++++++++++++++++++++++++++++++++++-- include/linux/blk_types.h | 66 +++++++++++++++++++++++++++++++++-- include/linux/types.h | 2 +- 3 files changed, 135 insertions(+), 6 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index 6d7d53030d7c..e5cd4ff08f5c 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -947,14 +947,22 @@ static blk_qc_t __submit_bio_noacct(struct bio *bio) { struct bio_list bio_list_on_stack[2]; blk_qc_t ret = BLK_QC_T_NONE; + struct request_queue *top_q; + bool poll_on; BUG_ON(bio->bi_next); bio_list_init(&bio_list_on_stack[0]); current->bio_list = bio_list_on_stack; + top_q = bio->bi_bdev->bd_disk->queue; + poll_on = test_bit(QUEUE_FLAG_POLL, &top_q->queue_flags) && + (bio->bi_opf & REQ_HIPRI); + do { - struct request_queue *q = bio->bi_bdev->bd_disk->queue; + blk_qc_t cookie; + struct block_device *bdev = bio->bi_bdev; + struct request_queue *q = bdev->bd_disk->queue; struct bio_list lower, same; if (unlikely(bio_queue_enter(bio) != 0)) @@ -966,7 +974,23 @@ static blk_qc_t __submit_bio_noacct(struct bio *bio) bio_list_on_stack[1] = bio_list_on_stack[0]; bio_list_init(&bio_list_on_stack[0]); - ret = __submit_bio(bio); + cookie = __submit_bio(bio); + + if (poll_on && blk_qc_t_valid(cookie)) { + unsigned int queue_num = blk_qc_t_to_queue_num(cookie); + unsigned int devt = bdev_whole(bdev)->bd_dev; + + cookie = blk_qc_t_get_by_devt(devt, queue_num); + + if (!blk_qc_t_valid(ret)) { + /* set initial value */ + ret = cookie; + } else if (ret != cookie) { + /* bio gets split and enqueued to multi hctxs */ + ret = BLK_QC_T_BIO_POLL_ALL; + poll_on = false; + } + } /* * Sort new bios into those for a lower level and those for the @@ -989,6 +1013,7 @@ static blk_qc_t __submit_bio_noacct(struct bio *bio) } while ((bio = bio_list_pop(&bio_list_on_stack[0]))); current->bio_list = NULL; + return ret; } @@ -1119,6 +1144,44 @@ blk_qc_t submit_bio(struct bio *bio) } EXPORT_SYMBOL(submit_bio); +static int blk_poll_bio(blk_qc_t cookie) +{ + unsigned int devt = blk_qc_t_to_devt(cookie); + unsigned int queue_num = blk_qc_t_to_queue_num(cookie); + struct block_device *bdev; + struct request_queue *q; + struct blk_mq_hw_ctx *hctx; + int ret; + + bdev = blkdev_get_no_open(devt); + + /* + * One such case is that dm device has reloaded table and the original + * underlying device the bio submitted to has been detached. When + * reloading table, dm will ensure that previously submitted IOs have + * all completed, thus return directly here. + */ + if (!bdev) + return 1; + + q = bdev->bd_disk->queue; + hctx = q->queue_hw_ctx[queue_num]; + + /* + * Similar to the case described in the above comment, that dm device + * has reloaded table and the original underlying device the bio + * submitted to has been detached. Thus the dev_t stored in cookie may + * be reused by another blkdev, and if that's the case, return directly + * here. + */ + if (hctx->type != HCTX_TYPE_POLL) + return 1; + + ret = blk_mq_poll_hctx(q, hctx); + + blkdev_put_no_open(bdev); + return ret; +} static int blk_bio_poll(struct request_queue *q, blk_qc_t cookie, bool spin) { @@ -1129,7 +1192,11 @@ static int blk_bio_poll(struct request_queue *q, blk_qc_t cookie, bool spin) do { int ret; - ret = disk->fops->poll(q, cookie); + if (unlikely(blk_qc_t_is_poll_multi(cookie))) + ret = disk->fops->poll(q, cookie); + else + ret = blk_poll_bio(cookie); + if (ret > 0) { __set_current_state(TASK_RUNNING); return ret; diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index fb429daaa909..8f970e026be9 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -505,10 +505,19 @@ static inline int op_stat_group(unsigned int op) return op_is_write(op); } -/* Macros for blk_qc_t */ +/* + * blk_qc_t for request-based mq devices. + * 63 31 30 15 0 (bit) + * +----------------------+-+-----------+-----------+ + * | reserved | | queue_num | tag | + * +----------------------+-+-----------+-----------+ + * ^ + * BLK_QC_T_INTERNAL + */ #define BLK_QC_T_NONE -1U #define BLK_QC_T_SHIFT 16 #define BLK_QC_T_INTERNAL (1U << 31) +#define BLK_QC_T_QUEUE_NUM_SIZE 15 static inline bool blk_qc_t_valid(blk_qc_t cookie) { @@ -517,7 +526,8 @@ static inline bool blk_qc_t_valid(blk_qc_t cookie) static inline unsigned int blk_qc_t_to_queue_num(blk_qc_t cookie) { - return (cookie & ~BLK_QC_T_INTERNAL) >> BLK_QC_T_SHIFT; + return (cookie >> BLK_QC_T_SHIFT) & + ((1u << BLK_QC_T_QUEUE_NUM_SIZE) - 1); } static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie) @@ -530,6 +540,58 @@ static inline bool blk_qc_t_is_internal(blk_qc_t cookie) return (cookie & BLK_QC_T_INTERNAL) != 0; } +/* + * blk_qc_t for bio-based devices. + * + * 1. When @bio is not split, the returned cookie has following format. + * @dev_t specifies the dev_t number of the underlying device the bio + * submitted to, while @queue_num specifies the hw queue the bio submitted + * to. + * + * 63 31 30 15 0 (bit) + * +----------------------+-+-----------+-----------+ + * | dev_t | | queue_num | reserved | + * +----------------------+-+-----------+-----------+ + * ^ + * reserved for compatibility with mq + * + * 2. When @bio gets split and enqueued into multi hw queues, the returned + * cookie is just BLK_QC_T_BIO_POLL_ALL flag. + * + * 63 0 (bit) + * +----------------------------------------------+-+ + * | |1| + * +----------------------------------------------+-+ + * ^ + * BLK_QC_T_BIO_POLL_ALL + * + * 3. Otherwise, return BLK_QC_T_NONE as the cookie. + * + * 63 0 (bit) + * +-----------------------------------------------+ + * | BLK_QC_T_NONE | + * +-----------------------------------------------+ + */ +#define BLK_QC_T_HIGH_SHIFT 32 +#define BLK_QC_T_BIO_POLL_ALL 1U + +static inline unsigned int blk_qc_t_to_devt(blk_qc_t cookie) +{ + return cookie >> BLK_QC_T_HIGH_SHIFT; +} + +static inline blk_qc_t blk_qc_t_get_by_devt(unsigned int dev, + unsigned int queue_num) +{ + return ((blk_qc_t)dev << BLK_QC_T_HIGH_SHIFT) | + (queue_num << BLK_QC_T_SHIFT); +} + +static inline bool blk_qc_t_is_poll_multi(blk_qc_t cookie) +{ + return cookie & BLK_QC_T_BIO_POLL_ALL; +} + struct blk_rq_stat { u64 mean; u64 min; diff --git a/include/linux/types.h b/include/linux/types.h index 52a54ed6ffac..7ff4bb96e0ea 100644 --- a/include/linux/types.h +++ b/include/linux/types.h @@ -126,7 +126,7 @@ typedef u64 sector_t; typedef u64 blkcnt_t; /* cookie used for IO polling */ -typedef unsigned int blk_qc_t; +typedef u64 blk_qc_t; /* * The type of an index into the pagecache. From patchwork Wed Mar 3 11:57:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 12113885 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=-16.8 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 27CD8C4332E for ; Wed, 3 Mar 2021 16:43:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 097CE64E6F for ; Wed, 3 Mar 2021 16:43:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346957AbhCCQjP (ORCPT ); Wed, 3 Mar 2021 11:39:15 -0500 Received: from out30-43.freemail.mail.aliyun.com ([115.124.30.43]:50429 "EHLO out30-43.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1442252AbhCCL6m (ORCPT ); Wed, 3 Mar 2021 06:58:42 -0500 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=e01e04420;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0UQGHkCe_1614772672; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0UQGHkCe_1614772672) by smtp.aliyun-inc.com(127.0.0.1); Wed, 03 Mar 2021 19:57:52 +0800 From: Jeffle Xu To: msnitzer@redhat.com, axboe@kernel.dk Cc: io-uring@vger.kernel.org, dm-devel@redhat.com, linux-block@vger.kernel.org, mpatocka@redhat.com, caspar@linux.alibaba.com, joseph.qi@linux.alibaba.com Subject: [PATCH v5 11/12] block: sub-fastpath for bio-based polling Date: Wed, 3 Mar 2021 19:57:39 +0800 Message-Id: <20210303115740.127001-12-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210303115740.127001-1-jefflexu@linux.alibaba.com> References: <20210303115740.127001-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Offer one sub-fastpath for bio-based polling when bio submitted to dm device gets split and enqueued into multiple hw queues, while the IO submission process has not been migrated to another CPU. In this case, the IO submission routine will return the CPU number on which the IO submission happened as the returned cookie, while the polling routine will only iterate and poll on hw queues that this CPU number maps, instead of iterating *all* hw queues. This optimization can dramatically reduce cache ping-pong and thus improve the polling performance, when multiple hw queues in polling mode per device could be reserved when there are multiple polling processes. It will fall back to iterating all hw queues in polling mode, once the process has ever been migrated to another CPU during the IO submission phase. Signed-off-by: Jeffle Xu --- block/blk-core.c | 18 ++++++++++++++++-- include/linux/blk_types.h | 38 ++++++++++++++++++++++++++++++++++---- 2 files changed, 50 insertions(+), 6 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index e5cd4ff08f5c..5479fd74d3be 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -948,7 +948,8 @@ static blk_qc_t __submit_bio_noacct(struct bio *bio) struct bio_list bio_list_on_stack[2]; blk_qc_t ret = BLK_QC_T_NONE; struct request_queue *top_q; - bool poll_on; + bool orig_poll_on, poll_on; + u64 old_nr_migrations; BUG_ON(bio->bi_next); @@ -958,6 +959,8 @@ static blk_qc_t __submit_bio_noacct(struct bio *bio) top_q = bio->bi_bdev->bd_disk->queue; poll_on = test_bit(QUEUE_FLAG_POLL, &top_q->queue_flags) && (bio->bi_opf & REQ_HIPRI); + orig_poll_on = poll_on; + old_nr_migrations = READ_ONCE(current->se.nr_migrations); do { blk_qc_t cookie; @@ -987,7 +990,7 @@ static blk_qc_t __submit_bio_noacct(struct bio *bio) ret = cookie; } else if (ret != cookie) { /* bio gets split and enqueued to multi hctxs */ - ret = BLK_QC_T_BIO_POLL_ALL; + ret = blk_qc_t_get_by_cpu(); poll_on = false; } } @@ -1014,6 +1017,17 @@ static blk_qc_t __submit_bio_noacct(struct bio *bio) current->bio_list = NULL; + /* + * For cases when bio gets split and enqueued into multi hctxs, return + * the corresponding CPU number when current process has not been + * migrated to another CPU. Return BLK_QC_T_BIO_POLL_ALL otherwise, + * falling back to iterating and polling on all hw queues, since split + * bios are submitted to different CPUs in this case. + */ + if (orig_poll_on != poll_on && + old_nr_migrations != READ_ONCE(current->se.nr_migrations)) + ret = BLK_QC_T_BIO_POLL_ALL; + return ret; } diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 8f970e026be9..32de4fb79eff 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -555,8 +555,21 @@ static inline bool blk_qc_t_is_internal(blk_qc_t cookie) * ^ * reserved for compatibility with mq * - * 2. When @bio gets split and enqueued into multi hw queues, the returned - * cookie is just BLK_QC_T_BIO_POLL_ALL flag. + * 2. When @bio gets split and enqueued into multi hw queues, and current + * process has *not* been migrated to another CPU, the returned cookie + * actually stores the corresponding CPU number on which the IO submission + * happened. Also with BLK_QC_T_BIO_POLL_CPU flag set. + * + * 63 31 0 (bit) + * +----------------------+-----------------------+-+ + * | cpu | |1| + * +----------------------+-----------------------+-+ + * ^ + * BLK_QC_T_BIO_POLL_CPU + * + * 3. When @bio gets split and enqueued into multi hw queues, and current + * process has ever been migrated to another CPU, the returned cookie is just + * BLK_QC_T_BIO_POLL_ALL flag. * * 63 0 (bit) * +----------------------------------------------+-+ @@ -565,7 +578,7 @@ static inline bool blk_qc_t_is_internal(blk_qc_t cookie) * ^ * BLK_QC_T_BIO_POLL_ALL * - * 3. Otherwise, return BLK_QC_T_NONE as the cookie. + * 4. Otherwise, return BLK_QC_T_NONE as the cookie. * * 63 0 (bit) * +-----------------------------------------------+ @@ -574,12 +587,18 @@ static inline bool blk_qc_t_is_internal(blk_qc_t cookie) */ #define BLK_QC_T_HIGH_SHIFT 32 #define BLK_QC_T_BIO_POLL_ALL 1U +#define BLK_QC_T_BIO_POLL_CPU 2U static inline unsigned int blk_qc_t_to_devt(blk_qc_t cookie) { return cookie >> BLK_QC_T_HIGH_SHIFT; } +static inline unsigned int blk_qc_t_to_cpu(blk_qc_t cookie) +{ + return cookie >> BLK_QC_T_HIGH_SHIFT; +} + static inline blk_qc_t blk_qc_t_get_by_devt(unsigned int dev, unsigned int queue_num) { @@ -587,9 +606,20 @@ static inline blk_qc_t blk_qc_t_get_by_devt(unsigned int dev, (queue_num << BLK_QC_T_SHIFT); } +static inline blk_qc_t blk_qc_t_get_by_cpu(void) +{ + return ((blk_qc_t)raw_smp_processor_id() << BLK_QC_T_HIGH_SHIFT) | + BLK_QC_T_BIO_POLL_CPU; +} + static inline bool blk_qc_t_is_poll_multi(blk_qc_t cookie) { - return cookie & BLK_QC_T_BIO_POLL_ALL; + return cookie & (BLK_QC_T_BIO_POLL_ALL | BLK_QC_T_BIO_POLL_CPU); +} + +static inline bool blk_qc_t_is_poll_cpu(blk_qc_t cookie) +{ + return cookie & BLK_QC_T_BIO_POLL_CPU; } struct blk_rq_stat { From patchwork Wed Mar 3 11:57:40 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 12113883 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=-16.8 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 CF996C433E9 for ; Wed, 3 Mar 2021 16:43:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A476C614A7 for ; Wed, 3 Mar 2021 16:43:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346875AbhCCQjJ (ORCPT ); Wed, 3 Mar 2021 11:39:09 -0500 Received: from out30-132.freemail.mail.aliyun.com ([115.124.30.132]:57053 "EHLO out30-132.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1442262AbhCCL6i (ORCPT ); Wed, 3 Mar 2021 06:58:38 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R621e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04394;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0UQGMHnb_1614772673; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0UQGMHnb_1614772673) by smtp.aliyun-inc.com(127.0.0.1); Wed, 03 Mar 2021 19:57:53 +0800 From: Jeffle Xu To: msnitzer@redhat.com, axboe@kernel.dk Cc: io-uring@vger.kernel.org, dm-devel@redhat.com, linux-block@vger.kernel.org, mpatocka@redhat.com, caspar@linux.alibaba.com, joseph.qi@linux.alibaba.com Subject: [PATCH v5 12/12] dm: support IO polling for bio-based dm device Date: Wed, 3 Mar 2021 19:57:40 +0800 Message-Id: <20210303115740.127001-13-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210303115740.127001-1-jefflexu@linux.alibaba.com> References: <20210303115740.127001-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org IO polling is enabled when all underlying target devices are capable of IO polling. The sanity check supports the stacked device model, in which one dm device may be build upon another dm device. In this case, the mapped device will check if the underlying dm target device supports IO polling. Signed-off-by: Jeffle Xu --- drivers/md/dm-table.c | 26 ++++++++++++ drivers/md/dm.c | 74 +++++++++++++++++++++++++++++++++++ include/linux/device-mapper.h | 1 + 3 files changed, 101 insertions(+) diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 95391f78b8d5..ed72349eb1db 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -1982,6 +1982,19 @@ static int device_requires_stable_pages(struct dm_target *ti, return blk_queue_stable_writes(q); } +static int device_not_poll_capable(struct dm_target *ti, struct dm_dev *dev, + sector_t start, sector_t len, void *data) +{ + struct request_queue *q = bdev_get_queue(dev->bdev); + + return !test_bit(QUEUE_FLAG_POLL, &q->queue_flags); +} + +int dm_table_supports_poll(struct dm_table *t) +{ + return !dm_table_any_dev_attr(t, device_not_poll_capable, NULL); +} + void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, struct queue_limits *limits) { @@ -2079,6 +2092,19 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, dm_update_keyslot_manager(q, t); blk_queue_update_readahead(q); + + /* + * 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, q); + else + blk_queue_flag_clear(QUEUE_FLAG_POLL, q); + } } unsigned int dm_table_get_num_targets(struct dm_table *t) diff --git a/drivers/md/dm.c b/drivers/md/dm.c index f1b76203b3c7..3f3f47d66386 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1714,6 +1714,78 @@ static blk_qc_t dm_submit_bio(struct bio *bio) return BLK_QC_T_NONE; } +struct dm_poll_data { + blk_qc_t cookie; + int count; +}; + +static int dm_poll_one_dev(struct dm_target *ti, struct dm_dev *dev, + sector_t start, sector_t len, void *data) +{ + struct dm_poll_data *pdata = data; + struct request_queue *q = bdev_get_queue(dev->bdev); + + if (queue_is_mq(q)) { + struct blk_mq_hw_ctx *hctx; + int i, cpu; + + if (!percpu_ref_tryget(&q->q_usage_counter)) + return 0; + + if (blk_qc_t_is_poll_cpu(pdata->cookie)) { + cpu = blk_qc_t_to_cpu(pdata->cookie); + hctx = blk_mq_get_hctx(q, cpu, REQ_HIPRI); + pdata->count += blk_mq_poll_hctx(q, hctx); + } else { + queue_for_each_poll_hw_ctx(q, hctx, i) + pdata->count += blk_mq_poll_hctx(q, hctx); + } + + percpu_ref_put(&q->q_usage_counter); + } else { + struct gendisk *disk = dev->bdev->bd_disk; + + pdata->count += disk->fops->poll(q, pdata->cookie); + } + + return 0; +} + +static int dm_bio_poll(struct request_queue *q, blk_qc_t cookie) +{ + int i, srcu_idx; + struct dm_table *t; + struct dm_target *ti; + struct mapped_device *md = queue_to_disk(q)->private_data; + struct dm_poll_data pdata = { + .cookie = cookie, + }; + + t = dm_get_live_table(md, &srcu_idx); + + for (i = 0; i < dm_table_get_num_targets(t); i++) { + ti = dm_table_get_target(t, i); + ti->type->iterate_devices(ti, dm_poll_one_dev, &pdata); + } + + dm_put_live_table(md, srcu_idx); + + return pdata.count; +} + +static bool dm_bio_poll_capable(struct gendisk *disk) +{ + int ret, srcu_idx; + struct mapped_device *md = disk->private_data; + struct dm_table *t; + + t = dm_get_live_table(md, &srcu_idx); + ret = dm_table_supports_poll(t); + dm_put_live_table(md, srcu_idx); + + return ret; +} + /*----------------------------------------------------------------- * An IDR is used to keep track of allocated minor numbers. *---------------------------------------------------------------*/ @@ -3126,6 +3198,8 @@ static const struct pr_ops dm_pr_ops = { }; static const struct block_device_operations dm_blk_dops = { + .poll = dm_bio_poll, + .poll_capable = dm_bio_poll_capable, .submit_bio = dm_submit_bio, .open = dm_blk_open, .release = dm_blk_close, diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h index 7f4ac87c0b32..31bfd6f70013 100644 --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -538,6 +538,7 @@ unsigned int dm_table_get_num_targets(struct dm_table *t); fmode_t dm_table_get_mode(struct dm_table *t); struct mapped_device *dm_table_get_md(struct dm_table *t); const char *dm_table_device_name(struct dm_table *t); +int dm_table_supports_poll(struct dm_table *t); /* * Trigger an event.