From patchwork Mon Mar 29 15:26:11 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 12170375 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 D14FEC433E0 for ; Mon, 29 Mar 2021 15:27:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9131D6196C for ; Mon, 29 Mar 2021 15:27:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231126AbhC2P1O (ORCPT ); Mon, 29 Mar 2021 11:27:14 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:53688 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231363AbhC2P04 (ORCPT ); Mon, 29 Mar 2021 11:26:56 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617031615; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=zeLuhTKZTjrPFVwDSbBTuK0mDGAAolQpa4vkOauA5k8=; b=QsRYJvuJmRRKXl4ZLjJp4CXjLVkp8u1gwDKTcI2w1knPPNi4Jie1KIlMWv+yD5xbEOXZhL 1PH4EkP3rRuoOu8k5zJKYrXm6cu54giq/7YN8eN1uNdtfmqjqlZhy8mqD1BPmxfTZ2vVP/ yjzY1EnoW2CxhhvalIsZn9qj7da93Rc= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-463-Ni7VIfVxN7irItanSOLnvQ-1; Mon, 29 Mar 2021 11:26:53 -0400 X-MC-Unique: Ni7VIfVxN7irItanSOLnvQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 2B644180FCAB; Mon, 29 Mar 2021 15:26:52 +0000 (UTC) Received: from localhost (ovpn-12-50.pek2.redhat.com [10.72.12.50]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0BEB46061F; Mon, 29 Mar 2021 15:26:41 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Jeffle Xu , Mike Snitzer , dm-devel@redhat.com, Hannes Reinecke , Ming Lei , Chaitanya Kulkarni Subject: [PATCH V4 01/12] block: add helper of blk_queue_poll Date: Mon, 29 Mar 2021 23:26:11 +0800 Message-Id: <20210329152622.173035-2-ming.lei@redhat.com> In-Reply-To: <20210329152622.173035-1-ming.lei@redhat.com> References: <20210329152622.173035-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org There has been 3 users, and will be more, so add one such helper. Reviewed-by: Chaitanya Kulkarni Reviewed-by: Jeffle Xu Reviewed-by: Hannes Reinecke Signed-off-by: Ming Lei --- block/blk-core.c | 2 +- block/blk-mq.c | 3 +-- block/blk-sysfs.c | 2 +- drivers/nvme/host/core.c | 2 +- include/linux/blkdev.h | 1 + 5 files changed, 5 insertions(+), 5 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index fc60ff208497..a31371d55b9d 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -836,7 +836,7 @@ static noinline_for_stack bool submit_bio_checks(struct bio *bio) } } - if (!test_bit(QUEUE_FLAG_POLL, &q->queue_flags)) + if (!blk_queue_poll(q)) bio->bi_opf &= ~REQ_HIPRI; switch (bio_op(bio)) { diff --git a/block/blk-mq.c b/block/blk-mq.c index d4d7c1caa439..63c81df3b8b5 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3869,8 +3869,7 @@ int blk_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)) + if (!blk_qc_t_valid(cookie) || !blk_queue_poll(q)) return 0; if (current->plug) diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 0f4f0c8a7825..db3268d41274 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -417,7 +417,7 @@ static ssize_t queue_poll_delay_store(struct request_queue *q, const char *page, static ssize_t queue_poll_show(struct request_queue *q, char *page) { - return queue_var_show(test_bit(QUEUE_FLAG_POLL, &q->queue_flags), page); + return queue_var_show(blk_queue_poll(q), page); } static ssize_t queue_poll_store(struct request_queue *q, const char *page, diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 0896e21642be..34b8c78f88e0 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -956,7 +956,7 @@ static void nvme_execute_rq_polled(struct request_queue *q, { DECLARE_COMPLETION_ONSTACK(wait); - WARN_ON_ONCE(!test_bit(QUEUE_FLAG_POLL, &q->queue_flags)); + WARN_ON_ONCE(!blk_queue_poll(q)); rq->cmd_flags |= REQ_HIPRI; rq->end_io_data = &wait; diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index bc6bc8383b43..89a01850cf12 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -665,6 +665,7 @@ bool blk_queue_flag_test_and_set(unsigned int flag, struct request_queue *q); #define blk_queue_fua(q) test_bit(QUEUE_FLAG_FUA, &(q)->queue_flags) #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) extern void blk_set_pm_only(struct request_queue *q); extern void blk_clear_pm_only(struct request_queue *q); From patchwork Mon Mar 29 15:26:12 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 12170377 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 C0BB3C433E0 for ; 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Mon, 29 Mar 2021 11:27:31 -0400 X-MC-Unique: O168gCcHPuK7vbQe-URLNA-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3FD08108BD17; Mon, 29 Mar 2021 15:27:28 +0000 (UTC) Received: from localhost (ovpn-12-50.pek2.redhat.com [10.72.12.50]) by smtp.corp.redhat.com (Postfix) with ESMTP id 895A959441; Mon, 29 Mar 2021 15:26:55 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Jeffle Xu , Mike Snitzer , dm-devel@redhat.com, Hannes Reinecke , Ming Lei Subject: [PATCH V4 02/12] block: add one helper to free io_context Date: Mon, 29 Mar 2021 23:26:12 +0800 Message-Id: <20210329152622.173035-3-ming.lei@redhat.com> In-Reply-To: <20210329152622.173035-1-ming.lei@redhat.com> References: <20210329152622.173035-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Prepare for putting bio poll queue into io_context, so add one helper for free io_context. Reviewed-by: Hannes Reinecke Signed-off-by: Ming Lei --- block/blk-ioc.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/block/blk-ioc.c b/block/blk-ioc.c index 57299f860d41..b0cde18c4b8c 100644 --- a/block/blk-ioc.c +++ b/block/blk-ioc.c @@ -17,6 +17,11 @@ */ static struct kmem_cache *iocontext_cachep; +static inline void free_io_context(struct io_context *ioc) +{ + kmem_cache_free(iocontext_cachep, ioc); +} + /** * get_io_context - increment reference count to io_context * @ioc: io_context to get @@ -129,7 +134,7 @@ static void ioc_release_fn(struct work_struct *work) spin_unlock_irq(&ioc->lock); - kmem_cache_free(iocontext_cachep, ioc); + free_io_context(ioc); } /** @@ -164,7 +169,7 @@ void put_io_context(struct io_context *ioc) } if (free_ioc) - kmem_cache_free(iocontext_cachep, ioc); + free_io_context(ioc); } /** @@ -278,7 +283,7 @@ int create_task_io_context(struct task_struct *task, gfp_t gfp_flags, int node) (task == current || !(task->flags & PF_EXITING))) task->io_context = ioc; else - kmem_cache_free(iocontext_cachep, ioc); + free_io_context(ioc); ret = task->io_context ? 0 : -EBUSY; From patchwork Mon Mar 29 15:26:13 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 12170379 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 A8861C433DB for ; Mon, 29 Mar 2021 15:28:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7C45F61920 for ; Mon, 29 Mar 2021 15:28:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230482AbhC2P1p (ORCPT ); Mon, 29 Mar 2021 11:27:45 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:23008 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231297AbhC2P1h (ORCPT ); Mon, 29 Mar 2021 11:27:37 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617031656; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/HpR7pU5Z2wT/dmFhvZrQXuEam+zMDtMGANHrIUN5Vg=; b=ROiQYDaFLhiB9IDoe5X9x1hXIt86Erl0Z1HY4yGzEeJGjL2vU+s8ef8obJd8/cFjWAKz3E dtL07XbmD6cHOwXU0vIDykmwXa8iKdBZP69HW8vc5pYu1yiOiPgNgpuF9YthHY0PmVC5Pj G9EZ/uv1mnnNVu4lP1o3zu2sgvvPpe8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-557-WIxElZe2Nf-di9zcISduNg-1; Mon, 29 Mar 2021 11:27:33 -0400 X-MC-Unique: WIxElZe2Nf-di9zcISduNg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 44CE39CDC4; Mon, 29 Mar 2021 15:27:32 +0000 (UTC) Received: from localhost (ovpn-12-50.pek2.redhat.com [10.72.12.50]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0107E5C5DF; Mon, 29 Mar 2021 15:27:30 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Jeffle Xu , Mike Snitzer , dm-devel@redhat.com, Hannes Reinecke , Ming Lei Subject: [PATCH V4 03/12] block: create io poll context for submission and poll task Date: Mon, 29 Mar 2021 23:26:13 +0800 Message-Id: <20210329152622.173035-4-ming.lei@redhat.com> In-Reply-To: <20210329152622.173035-1-ming.lei@redhat.com> References: <20210329152622.173035-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Create per-task io poll context for both IO submission and poll task if the queue is bio based and supports polling. This io polling context includes two queues: 1) submission queue(sq) for storing HIPRI bio, written by submission task and read by poll task. 2) polling queue(pq) for holding data moved from sq, only used in poll context for running bio polling. Following patches will support bio based io polling. Signed-off-by: Ming Lei Reviewed-by: Jeffle Xu --- block/blk-core.c | 79 +++++++++++++++++++++++++++++++++------ block/blk-ioc.c | 1 + block/blk-mq.c | 14 +++++++ block/blk.h | 38 +++++++++++++++++++ include/linux/iocontext.h | 2 + 5 files changed, 123 insertions(+), 11 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index a31371d55b9d..8a21a8c010a6 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -792,6 +792,61 @@ static inline blk_status_t blk_check_zone_append(struct request_queue *q, return BLK_STS_OK; } +static inline struct blk_bio_poll_ctx *blk_get_bio_poll_ctx(void) +{ + struct io_context *ioc = current->io_context; + + return ioc ? ioc->data : NULL; +} + +static inline unsigned int bio_grp_list_size(unsigned int nr_grps) +{ + return sizeof(struct bio_grp_list) + nr_grps * + sizeof(struct bio_grp_list_data); +} + +static void bio_poll_ctx_init(struct blk_bio_poll_ctx *pc) +{ + pc->sq = (void *)pc + sizeof(*pc); + pc->sq->max_nr_grps = BLK_BIO_POLL_SQ_SZ; + + pc->pq = (void *)pc->sq + bio_grp_list_size(BLK_BIO_POLL_SQ_SZ); + pc->pq->max_nr_grps = BLK_BIO_POLL_PQ_SZ; + + spin_lock_init(&pc->sq_lock); + spin_lock_init(&pc->pq_lock); +} + +void bio_poll_ctx_alloc(struct io_context *ioc) +{ + struct blk_bio_poll_ctx *pc; + unsigned int size = sizeof(*pc) + + bio_grp_list_size(BLK_BIO_POLL_SQ_SZ) + + bio_grp_list_size(BLK_BIO_POLL_PQ_SZ); + + pc = kzalloc(GFP_ATOMIC, size); + if (pc) { + bio_poll_ctx_init(pc); + if (cmpxchg(&ioc->data, NULL, (void *)pc)) + kfree(pc); + } +} + +static inline bool blk_queue_support_bio_poll(struct request_queue *q) +{ + return !queue_is_mq(q) && blk_queue_poll(q); +} + +static inline void blk_bio_poll_preprocess(struct request_queue *q, + struct bio *bio) +{ + if (!(bio->bi_opf & REQ_HIPRI)) + return; + + if (!blk_queue_poll(q) || (!queue_is_mq(q) && !blk_get_bio_poll_ctx())) + bio->bi_opf &= ~REQ_HIPRI; +} + static noinline_for_stack bool submit_bio_checks(struct bio *bio) { struct block_device *bdev = bio->bi_bdev; @@ -836,8 +891,19 @@ static noinline_for_stack bool submit_bio_checks(struct bio *bio) } } - if (!blk_queue_poll(q)) - bio->bi_opf &= ~REQ_HIPRI; + /* + * Various block parts want %current->io_context, so allocate it up + * front rather than dealing with lots of pain to allocate it only + * where needed. This may fail and the block layer knows how to live + * with it. + */ + if (unlikely(!current->io_context)) + create_task_io_context(current, GFP_ATOMIC, q->node); + + if (blk_queue_support_bio_poll(q) && (bio->bi_opf & REQ_HIPRI)) + blk_create_io_poll_context(q); + + blk_bio_poll_preprocess(q, bio); switch (bio_op(bio)) { case REQ_OP_DISCARD: @@ -876,15 +942,6 @@ static noinline_for_stack bool submit_bio_checks(struct bio *bio) break; } - /* - * Various block parts want %current->io_context, so allocate it up - * front rather than dealing with lots of pain to allocate it only - * where needed. This may fail and the block layer knows how to live - * with it. - */ - if (unlikely(!current->io_context)) - create_task_io_context(current, GFP_ATOMIC, q->node); - if (blk_throtl_bio(bio)) { blkcg_bio_issue_init(bio); return false; diff --git a/block/blk-ioc.c b/block/blk-ioc.c index b0cde18c4b8c..5574c398eff6 100644 --- a/block/blk-ioc.c +++ b/block/blk-ioc.c @@ -19,6 +19,7 @@ static struct kmem_cache *iocontext_cachep; static inline void free_io_context(struct io_context *ioc) { + kfree(ioc->data); kmem_cache_free(iocontext_cachep, ioc); } diff --git a/block/blk-mq.c b/block/blk-mq.c index 63c81df3b8b5..1ada2c0e76b1 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3852,6 +3852,17 @@ static bool blk_mq_poll_hybrid(struct request_queue *q, return blk_mq_poll_hybrid_sleep(q, rq); } +static int blk_bio_poll(struct request_queue *q, blk_qc_t cookie, bool spin) +{ + /* + * Create poll queue for storing poll bio and its cookie from + * submission queue + */ + blk_create_io_poll_context(q); + + return 0; +} + /** * blk_poll - poll for IO completions * @q: the queue @@ -3875,6 +3886,9 @@ int blk_poll(struct request_queue *q, blk_qc_t cookie, bool spin) if (current->plug) blk_flush_plug_list(current->plug, false); + if (!queue_is_mq(q)) + return blk_bio_poll(q, cookie, spin); + hctx = q->queue_hw_ctx[blk_qc_t_to_queue_num(cookie)]; /* diff --git a/block/blk.h b/block/blk.h index 3b53e44b967e..35901cee709d 100644 --- a/block/blk.h +++ b/block/blk.h @@ -357,4 +357,42 @@ int bio_add_hw_page(struct request_queue *q, struct bio *bio, struct page *page, unsigned int len, unsigned int offset, unsigned int max_sectors, bool *same_page); +/* Grouping bios that share same data into one list */ +struct bio_grp_list_data { + void *grp_data; + + /* all bios in this list share same 'grp_data' */ + struct bio_list list; +}; + +struct bio_grp_list { + unsigned int max_nr_grps, nr_grps; + struct bio_grp_list_data head[0]; +}; + +struct blk_bio_poll_ctx { + spinlock_t sq_lock; + struct bio_grp_list *sq; + + spinlock_t pq_lock; + struct bio_grp_list *pq; +}; + +#define BLK_BIO_POLL_SQ_SZ 16U +#define BLK_BIO_POLL_PQ_SZ (BLK_BIO_POLL_SQ_SZ * 2) + +void bio_poll_ctx_alloc(struct io_context *ioc); + +static inline void blk_create_io_poll_context(struct request_queue *q) +{ + struct io_context *ioc; + + if (unlikely(!current->io_context)) + create_task_io_context(current, GFP_ATOMIC, q->node); + + ioc = current->io_context; + if (unlikely(ioc && !ioc->data)) + bio_poll_ctx_alloc(ioc); +} + #endif /* BLK_INTERNAL_H */ diff --git a/include/linux/iocontext.h b/include/linux/iocontext.h index 0a9dc40b7be8..f9a467571356 100644 --- a/include/linux/iocontext.h +++ b/include/linux/iocontext.h @@ -110,6 +110,8 @@ struct io_context { struct io_cq __rcu *icq_hint; struct hlist_head icq_list; + void *data; + struct work_struct release_work; }; From patchwork Mon Mar 29 15:26:14 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 12170383 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 2BA1BC433C1 for ; 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Mon, 29 Mar 2021 11:27:42 -0400 X-MC-Unique: Yy-jfXlVOR6NzHk2231uhQ-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B7E05802B7F; Mon, 29 Mar 2021 15:27:40 +0000 (UTC) Received: from localhost (ovpn-12-50.pek2.redhat.com [10.72.12.50]) by smtp.corp.redhat.com (Postfix) with ESMTP id D1DE25D6A1; Mon, 29 Mar 2021 15:27:34 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Jeffle Xu , Mike Snitzer , dm-devel@redhat.com, Hannes Reinecke , Ming Lei Subject: [PATCH V4 04/12] block: add req flag of REQ_POLL_CTX Date: Mon, 29 Mar 2021 23:26:14 +0800 Message-Id: <20210329152622.173035-5-ming.lei@redhat.com> In-Reply-To: <20210329152622.173035-1-ming.lei@redhat.com> References: <20210329152622.173035-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Add one req flag REQ_POLL_CTX which will be used in the following patch for supporting bio based IO polling. Exactly this flag can help us to do: 1) request flag is cloned in bio_fast_clone(), so if we mark one FS bio as REQ_POLL_CTX, all bios cloned from this FS bio will be marked as REQ_POLL_CTX too. 2) create per-task io polling context if the bio based queue supports polling and the submitted bio is HIPRI. Per-task io poll context will be created during submit_bio() before marking this HIPRI bio as REQ_POLL_CTX. Then we can avoid to create such io polling context if one cloned bio with REQ_POLL_CTX is submitted from another kernel context. 3) for supporting bio based io polling, we need to poll IOs from all underlying queues of the bio device, this way help us to recognize which IO needs to polled in bio based style, which will be applied in following patch. Reviewed-by: Jeffle Xu Signed-off-by: Ming Lei Reviewed-by: Hannes Reinecke --- block/blk-core.c | 28 ++++++++++++++++++++++++++-- include/linux/blk_types.h | 4 ++++ 2 files changed, 30 insertions(+), 2 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index 8a21a8c010a6..a777ba4fe06f 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -840,11 +840,30 @@ static inline bool blk_queue_support_bio_poll(struct request_queue *q) static inline void blk_bio_poll_preprocess(struct request_queue *q, struct bio *bio) { + bool mq; + if (!(bio->bi_opf & REQ_HIPRI)) return; - if (!blk_queue_poll(q) || (!queue_is_mq(q) && !blk_get_bio_poll_ctx())) + /* + * Can't support bio based IO polling without per-task poll ctx + * + * We have created per-task io poll context, and mark this + * bio as REQ_POLL_CTX, so: 1) if any cloned bio from this bio is + * submitted from another kernel context, we won't create bio + * poll context for it, and that bio can be completed by IRQ; + * 2) If such bio is submitted from current context, we will + * complete it via blk_poll(); 3) If driver knows that one + * underlying bio allocated from driver is for FS bio, meantime + * it is submitted in current context, driver can mark such bio + * as REQ_HIPRI & REQ_POLL_CTX manually, so the bio can be completed + * via blk_poll too. + */ + mq = queue_is_mq(q); + if (!blk_queue_poll(q) || (!mq && !blk_get_bio_poll_ctx())) bio->bi_opf &= ~REQ_HIPRI; + else if (!mq) + bio->bi_opf |= REQ_POLL_CTX; } static noinline_for_stack bool submit_bio_checks(struct bio *bio) @@ -900,7 +919,12 @@ static noinline_for_stack bool submit_bio_checks(struct bio *bio) if (unlikely(!current->io_context)) create_task_io_context(current, GFP_ATOMIC, q->node); - if (blk_queue_support_bio_poll(q) && (bio->bi_opf & REQ_HIPRI)) + /* + * If REQ_POLL_CTX isn't set for this HIPRI bio, we think it + * originated from FS and allocate io polling context. + */ + if (blk_queue_support_bio_poll(q) && (bio->bi_opf & REQ_HIPRI) && + !(bio->bi_opf & REQ_POLL_CTX)) blk_create_io_poll_context(q); blk_bio_poll_preprocess(q, bio); diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index db026b6ec15a..99160d588c2d 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -394,6 +394,9 @@ enum req_flag_bits { __REQ_HIPRI, + /* for marking IOs originated from same FS bio in same context */ + __REQ_POLL_CTX, + /* for driver use */ __REQ_DRV, __REQ_SWAP, /* swapping request. */ @@ -418,6 +421,7 @@ enum req_flag_bits { #define REQ_NOUNMAP (1ULL << __REQ_NOUNMAP) #define REQ_HIPRI (1ULL << __REQ_HIPRI) +#define REQ_POLL_CTX (1ULL << __REQ_POLL_CTX) #define REQ_DRV (1ULL << __REQ_DRV) #define REQ_SWAP (1ULL << __REQ_SWAP) From patchwork Mon Mar 29 15:26:15 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 12170381 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 952FEC433DB for ; Mon, 29 Mar 2021 15:28:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4FBF0617ED for ; Mon, 29 Mar 2021 15:28:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230447AbhC2P2S (ORCPT ); Mon, 29 Mar 2021 11:28:18 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:32492 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231244AbhC2P1u (ORCPT ); Mon, 29 Mar 2021 11:27:50 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617031669; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=yiAZ1LG/jl/FrJlJpKhJ5cneSmOPmuiOZBkRQiXX7gg=; b=Brprz7ffKPsxHymN9t5jRZTpw9NoFBtNm3mxx28os4+QzUTv8oLFbcyavONJT5K7/h37p1 FiDkzvDRUxjrbOwKuApW2Qfl8GTrLb8wCwpCw11/MAwn1F2ytF3TfEOxqbVVqLUSzirFe1 p7CTuepL+KIbvOTiPQQ4SVNhTumSSS4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-489-1uYXQKzJOy6aPs0Jlkcu7A-1; Mon, 29 Mar 2021 11:27:45 -0400 X-MC-Unique: 1uYXQKzJOy6aPs0Jlkcu7A-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 56EA0871377; Mon, 29 Mar 2021 15:27:44 +0000 (UTC) Received: from localhost (ovpn-12-50.pek2.redhat.com [10.72.12.50]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5ADCD5C5DF; Mon, 29 Mar 2021 15:27:43 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Jeffle Xu , Mike Snitzer , dm-devel@redhat.com, Hannes Reinecke , Ming Lei Subject: [PATCH V4 05/12] block: add new field into 'struct bvec_iter' Date: Mon, 29 Mar 2021 23:26:15 +0800 Message-Id: <20210329152622.173035-6-ming.lei@redhat.com> In-Reply-To: <20210329152622.173035-1-ming.lei@redhat.com> References: <20210329152622.173035-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org There is a hole at the end of 'struct bvec_iter', so put a new field here and we can save cookie returned from submit_bio() here for supporting bio based polling. This way can avoid to extend bio unnecessarily. Meantime add two helpers to get/set this field. Reviewed-by: Hannes Reinecke Signed-off-by: Ming Lei --- block/blk.h | 10 ++++++++++ include/linux/bvec.h | 8 ++++++++ 2 files changed, 18 insertions(+) diff --git a/block/blk.h b/block/blk.h index 35901cee709d..c1d8456656df 100644 --- a/block/blk.h +++ b/block/blk.h @@ -395,4 +395,14 @@ static inline void blk_create_io_poll_context(struct request_queue *q) bio_poll_ctx_alloc(ioc); } +static inline unsigned int bio_get_private_data(struct bio *bio) +{ + return bio->bi_iter.bi_private_data; +} + +static inline void bio_set_private_data(struct bio *bio, unsigned int data) +{ + bio->bi_iter.bi_private_data = data; +} + #endif /* BLK_INTERNAL_H */ diff --git a/include/linux/bvec.h b/include/linux/bvec.h index ff832e698efb..547ad7526960 100644 --- a/include/linux/bvec.h +++ b/include/linux/bvec.h @@ -43,6 +43,14 @@ struct bvec_iter { unsigned int bi_bvec_done; /* number of bytes completed in current bvec */ + + /* + * There is a hole at the end of bvec_iter, add one new field to hold + * something which isn't related with 'bvec_iter', so that we can + * avoid extending bio. So far this new field is used for bio based + * polling, we will store returning value of submit_bio() here. + */ + unsigned int bi_private_data; }; struct bvec_iter_all { From patchwork Mon Mar 29 15:26:16 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 12170385 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 79DABC433E2 for ; Mon, 29 Mar 2021 15:28:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 31FA361987 for ; Mon, 29 Mar 2021 15:28:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231270AbhC2P2T (ORCPT ); Mon, 29 Mar 2021 11:28:19 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:26263 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231196AbhC2P2C (ORCPT ); Mon, 29 Mar 2021 11:28:02 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617031681; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JmE5i/m5IEEsJrMpVFAKNyycD7jJsnJYAktcyMjzdnY=; b=a4ZBJY9jk51c1uMXCAxSOAsXLhSq8zPWgC3MAUcLDXbKVlxaFiO+yqFW/XGxWGePK0cbTQ jNqbRs9eOQ7QMhY9SXkKWzeJi4AKY6lZNZiL58E6memSfNSwsz840cHIfG90TmOAWYHMHe o59vdHauD6HFjYHIRbemALHXQAOvMVA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-35-0-6Bkd4LPt2Yz5pzvQWVWA-1; Mon, 29 Mar 2021 11:27:51 -0400 X-MC-Unique: 0-6Bkd4LPt2Yz5pzvQWVWA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B9330807341; Mon, 29 Mar 2021 15:27:49 +0000 (UTC) Received: from localhost (ovpn-12-50.pek2.redhat.com [10.72.12.50]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6715B5D6A1; Mon, 29 Mar 2021 15:27:46 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Jeffle Xu , Mike Snitzer , dm-devel@redhat.com, Hannes Reinecke , Ming Lei Subject: [PATCH V4 06/12] block/mq: extract one helper function polling hw queue Date: Mon, 29 Mar 2021 23:26:16 +0800 Message-Id: <20210329152622.173035-7-ming.lei@redhat.com> In-Reply-To: <20210329152622.173035-1-ming.lei@redhat.com> References: <20210329152622.173035-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org From: Jeffle Xu Extract the logic of polling one hw queue and related statistics handling out as the helper function. Reviewed-by: Hannes Reinecke Signed-off-by: Jeffle Xu Signed-off-by: Ming Lei --- block/blk-mq.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 1ada2c0e76b1..0cb88c719916 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3852,6 +3852,19 @@ static bool blk_mq_poll_hybrid(struct request_queue *q, return blk_mq_poll_hybrid_sleep(q, rq); } +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; +} + static int blk_bio_poll(struct request_queue *q, blk_qc_t cookie, bool spin) { /* @@ -3908,11 +3921,8 @@ int blk_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; } From patchwork Mon Mar 29 15:26:17 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 12170389 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 8ADF3C433E4 for ; Mon, 29 Mar 2021 15:28:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 549316196E for ; Mon, 29 Mar 2021 15:28:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231244AbhC2P2S (ORCPT ); Mon, 29 Mar 2021 11:28:18 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:20671 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231270AbhC2P15 (ORCPT ); Mon, 29 Mar 2021 11:27:57 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617031676; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=fNlG+3ho3blgJVyFVypZc5c3TnkhPbJk0ckqheigCu8=; b=DJeaqRz+bhmKXKte+4pa601xC2xvi9ydbYrJauroVB7c2JzwzDchy7GO+ez5civnDi4JUf BZOC4HPmyOQHAZu/BxFmaM8TGaIaGFKFQjh7JlHQ6t6u2Dzq63OZrAYEJr6Kp7WIRZKUzJ o1sllRYrQo+0/Of3DbhtbiphFH7GdcY= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-358-LGej-2lTNAWJ_5UslOIKxQ-1; Mon, 29 Mar 2021 11:27:54 -0400 X-MC-Unique: LGej-2lTNAWJ_5UslOIKxQ-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 574D287A83B; Mon, 29 Mar 2021 15:27:53 +0000 (UTC) Received: from localhost (ovpn-12-50.pek2.redhat.com [10.72.12.50]) by smtp.corp.redhat.com (Postfix) with ESMTP id 622EA5D6A1; Mon, 29 Mar 2021 15:27:52 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Jeffle Xu , Mike Snitzer , dm-devel@redhat.com, Hannes Reinecke , Ming Lei Subject: [PATCH V4 07/12] block: prepare for supporting bio_list via other link Date: Mon, 29 Mar 2021 23:26:17 +0800 Message-Id: <20210329152622.173035-8-ming.lei@redhat.com> In-Reply-To: <20210329152622.173035-1-ming.lei@redhat.com> References: <20210329152622.173035-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org So far bio list helpers always use .bi_next to traverse the list, we will support to link bios by other bio field. Prepare for such support by adding a macro so that users can define another helpers for linking bios by other bio field. Reviewed-by: Hannes Reinecke Signed-off-by: Ming Lei --- include/linux/bio.h | 132 +++++++++++++++++++++++--------------------- 1 file changed, 68 insertions(+), 64 deletions(-) diff --git a/include/linux/bio.h b/include/linux/bio.h index d0246c92a6e8..619edd26a6c0 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -608,75 +608,11 @@ static inline unsigned bio_list_size(const struct bio_list *bl) return sz; } -static inline void bio_list_add(struct bio_list *bl, struct bio *bio) -{ - bio->bi_next = NULL; - - if (bl->tail) - bl->tail->bi_next = bio; - else - bl->head = bio; - - bl->tail = bio; -} - -static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio) -{ - bio->bi_next = bl->head; - - bl->head = bio; - - if (!bl->tail) - bl->tail = bio; -} - -static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2) -{ - if (!bl2->head) - return; - - if (bl->tail) - bl->tail->bi_next = bl2->head; - else - bl->head = bl2->head; - - bl->tail = bl2->tail; -} - -static inline void bio_list_merge_head(struct bio_list *bl, - struct bio_list *bl2) -{ - if (!bl2->head) - return; - - if (bl->head) - bl2->tail->bi_next = bl->head; - else - bl->tail = bl2->tail; - - bl->head = bl2->head; -} - static inline struct bio *bio_list_peek(struct bio_list *bl) { return bl->head; } -static inline struct bio *bio_list_pop(struct bio_list *bl) -{ - struct bio *bio = bl->head; - - if (bio) { - bl->head = bl->head->bi_next; - if (!bl->head) - bl->tail = NULL; - - bio->bi_next = NULL; - } - - return bio; -} - static inline struct bio *bio_list_get(struct bio_list *bl) { struct bio *bio = bl->head; @@ -686,6 +622,74 @@ static inline struct bio *bio_list_get(struct bio_list *bl) return bio; } +#define BIO_LIST_HELPERS(_pre, link) \ + \ +static inline void _pre##_add(struct bio_list *bl, struct bio *bio) \ +{ \ + bio->bi_##link = NULL; \ + \ + if (bl->tail) \ + bl->tail->bi_##link = bio; \ + else \ + bl->head = bio; \ + \ + bl->tail = bio; \ +} \ + \ +static inline void _pre##_add_head(struct bio_list *bl, struct bio *bio) \ +{ \ + bio->bi_##link = bl->head; \ + \ + bl->head = bio; \ + \ + if (!bl->tail) \ + bl->tail = bio; \ +} \ + \ +static inline void _pre##_merge(struct bio_list *bl, struct bio_list *bl2) \ +{ \ + if (!bl2->head) \ + return; \ + \ + if (bl->tail) \ + bl->tail->bi_##link = bl2->head; \ + else \ + bl->head = bl2->head; \ + \ + bl->tail = bl2->tail; \ +} \ + \ +static inline void _pre##_merge_head(struct bio_list *bl, \ + struct bio_list *bl2) \ +{ \ + if (!bl2->head) \ + return; \ + \ + if (bl->head) \ + bl2->tail->bi_##link = bl->head; \ + else \ + bl->tail = bl2->tail; \ + \ + bl->head = bl2->head; \ +} \ + \ +static inline struct bio *_pre##_pop(struct bio_list *bl) \ +{ \ + struct bio *bio = bl->head; \ + \ + if (bio) { \ + bl->head = bl->head->bi_##link; \ + if (!bl->head) \ + bl->tail = NULL; \ + \ + bio->bi_##link = NULL; \ + } \ + \ + return bio; \ +} \ + +BIO_LIST_HELPERS(bio_list, next); + /* * Increment chain count for the bio. Make sure the CHAIN flag update * is visible before the raised count. From patchwork Mon Mar 29 15:26:18 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 12170393 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 922ECC433E5 for ; Mon, 29 Mar 2021 15:28:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6E05361970 for ; Mon, 29 Mar 2021 15:28:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230516AbhC2P2U (ORCPT ); Mon, 29 Mar 2021 11:28:20 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:26361 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231381AbhC2P2I (ORCPT ); Mon, 29 Mar 2021 11:28:08 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617031687; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=wxhZXPofcJR9LD5xeC+OwkPhSjBL6yq2aENhxH2JJ7A=; b=WV3HsdldhHh1fI89be5+vULFPuQb1jczS6AQJVyT2bzSmVO97yTouGjvj6gX/zI/AUYjlr ti0XMkTrJM5FDr4R2b2Ol4T8UHkYDs3F7JP9jOdNBguJRkRHZq3+WuH9E1uGN5Y5fB7thm JJAcVpuVmKPFwEbeScT/B1R8TtD3P/A= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-538-Zf8zFdpEPZOrN_yqSBElGw-1; Mon, 29 Mar 2021 11:27:58 -0400 X-MC-Unique: Zf8zFdpEPZOrN_yqSBElGw-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3E93218C8C04; Mon, 29 Mar 2021 15:27:57 +0000 (UTC) Received: from localhost (ovpn-12-50.pek2.redhat.com [10.72.12.50]) by smtp.corp.redhat.com (Postfix) with ESMTP id 74D0F5D9F0; Mon, 29 Mar 2021 15:27:55 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Jeffle Xu , Mike Snitzer , dm-devel@redhat.com, Hannes Reinecke , Ming Lei Subject: [PATCH V4 08/12] block: use per-task poll context to implement bio based io polling Date: Mon, 29 Mar 2021 23:26:18 +0800 Message-Id: <20210329152622.173035-9-ming.lei@redhat.com> In-Reply-To: <20210329152622.173035-1-ming.lei@redhat.com> References: <20210329152622.173035-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Currently bio based IO polling needs to poll all hw queue blindly, this way is very inefficient, and one big reason is that we can't pass any bio submission result to blk_poll(). In IO submission context, track associated underlying bios by per-task submission queue and store returned 'cookie' in bio->bi_iter.bi_private_data, and return current->pid to caller of submit_bio() for any bio based driver's IO, which is submitted from FS. In IO poll context, the passed cookie tells us the PID of submission context, then we can find bios from the per-task io pull context of submission context. Moving bios from submission queue to poll queue of the poll context, and keep polling until these bios are ended. Remove bio from poll queue if the bio is ended. Add bio flags of BIO_DONE and BIO_END_BY_POLL for such purpose. In was found in Jeffle Xu's test that kfifo doesn't scale well for a submission queue as queue depth is increased, so a new mechanism for tracking bios is needed. So far bio's size is close to 2 cacheline size, and it may not be accepted to add new field into bio for solving the scalability issue by tracking bios via linked list, switch to bio group list for tracking bio, the idea is to reuse .bi_end_io for linking bios into a linked list for all sharing same .bi_end_io(call it bio group), which is recovered before ending bio really, since BIO_END_BY_POLL is added for enhancing this point. Usually .bi_end_bio is same for all bios in same layer, so it is enough to provide very limited groups, such as 16 or less for fixing the scalability issue. Usually submission shares context with io poll. The per-task poll context is just like stack variable, and it is cheap to move data between the two per-task queues. Also when the submission task is exiting, drain pending IOs in the context until all are done. Signed-off-by: Ming Lei Reviewed-by: Jeffle Xu --- block/bio.c | 5 + block/blk-core.c | 153 +++++++++++++++++++++++- block/blk-ioc.c | 3 + block/blk-mq.c | 240 +++++++++++++++++++++++++++++++++++++- block/blk.h | 10 ++ include/linux/blk_types.h | 18 ++- 6 files changed, 425 insertions(+), 4 deletions(-) diff --git a/block/bio.c b/block/bio.c index 26b7f721cda8..04c043dc60fc 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1402,6 +1402,11 @@ static inline bool bio_remaining_done(struct bio *bio) **/ void bio_endio(struct bio *bio) { + /* BIO_END_BY_POLL has to be set before calling submit_bio */ + if (bio_flagged(bio, BIO_END_BY_POLL)) { + bio_set_flag(bio, BIO_DONE); + return; + } again: if (!bio_remaining_done(bio)) return; diff --git a/block/blk-core.c b/block/blk-core.c index a777ba4fe06f..939730440693 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -805,6 +805,81 @@ static inline unsigned int bio_grp_list_size(unsigned int nr_grps) sizeof(struct bio_grp_list_data); } +static inline void *bio_grp_data(struct bio *bio) +{ + return bio->bi_poll; +} + +/* add bio into bio group list, return true if it is added */ +static bool bio_grp_list_add(struct bio_grp_list *list, struct bio *bio) +{ + int i; + struct bio_grp_list_data *grp; + + for (i = 0; i < list->nr_grps; i++) { + grp = &list->head[i]; + if (grp->grp_data == bio_grp_data(bio)) { + __bio_grp_list_add(&grp->list, bio); + return true; + } + } + + if (i == list->max_nr_grps) + return false; + + /* create a new group */ + grp = &list->head[i]; + bio_list_init(&grp->list); + grp->grp_data = bio_grp_data(bio); + __bio_grp_list_add(&grp->list, bio); + list->nr_grps++; + + return true; +} + +static int bio_grp_list_find_grp(struct bio_grp_list *list, void *grp_data) +{ + int i; + struct bio_grp_list_data *grp; + + for (i = 0; i < list->nr_grps; i++) { + grp = &list->head[i]; + if (grp->grp_data == grp_data) + return i; + } + + if (i < list->max_nr_grps) { + grp = &list->head[i]; + bio_list_init(&grp->list); + return i; + } + + return -1; +} + +/* Move as many as possible groups from 'src' to 'dst' */ +void bio_grp_list_move(struct bio_grp_list *dst, struct bio_grp_list *src) +{ + int i, j, cnt = 0; + struct bio_grp_list_data *grp; + + for (i = src->nr_grps - 1; i >= 0; i--) { + grp = &src->head[i]; + j = bio_grp_list_find_grp(dst, grp->grp_data); + if (j < 0) + break; + if (bio_grp_list_grp_empty(&dst->head[j])) { + dst->head[j].grp_data = grp->grp_data; + dst->nr_grps++; + } + __bio_grp_list_merge(&dst->head[j].list, &grp->list); + bio_list_init(&grp->list); + cnt++; + } + + src->nr_grps -= cnt; +} + static void bio_poll_ctx_init(struct blk_bio_poll_ctx *pc) { pc->sq = (void *)pc + sizeof(*pc); @@ -866,6 +941,45 @@ static inline void blk_bio_poll_preprocess(struct request_queue *q, bio->bi_opf |= REQ_POLL_CTX; } +static inline void blk_bio_poll_mark_queued(struct bio *bio, bool queued) +{ + /* + * The bio has been added to per-task poll queue, mark it as + * END_BY_POLL, so that this bio is always completed from + * blk_poll() which is provided with cookied from this bio's + * submission. + */ + if (!queued) + bio->bi_opf &= ~(REQ_HIPRI | REQ_POLL_CTX); + else + bio_set_flag(bio, BIO_END_BY_POLL); +} + +static bool blk_bio_poll_prep_submit(struct io_context *ioc, struct bio *bio) +{ + struct blk_bio_poll_ctx *pc = ioc->data; + unsigned int queued; + + /* + * We rely on immutable .bi_end_io between blk-mq bio submission + * and completion. However, bio crypt may update .bi_end_io during + * submission, so simply don't support bio based polling for this + * setting. + */ + if (likely(!bio_has_crypt_ctx(bio))) { + /* track this bio via bio group list */ + spin_lock(&pc->sq_lock); + queued = bio_grp_list_add(pc->sq, bio); + blk_bio_poll_mark_queued(bio, queued); + spin_unlock(&pc->sq_lock); + } else { + queued = false; + blk_bio_poll_mark_queued(bio, false); + } + + return queued; +} + static noinline_for_stack bool submit_bio_checks(struct bio *bio) { struct block_device *bdev = bio->bi_bdev; @@ -1024,7 +1138,7 @@ static blk_qc_t __submit_bio(struct bio *bio) * bio_list_on_stack[1] contains bios that were submitted before the current * ->submit_bio_bio, but that haven't been processed yet. */ -static blk_qc_t __submit_bio_noacct(struct bio *bio) +static blk_qc_t __submit_bio_noacct_ctx(struct bio *bio, struct io_context *ioc) { struct bio_list bio_list_on_stack[2]; blk_qc_t ret = BLK_QC_T_NONE; @@ -1047,7 +1161,15 @@ 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); + if (ioc && queue_is_mq(q) && (bio->bi_opf & REQ_HIPRI)) { + bool queued = blk_bio_poll_prep_submit(ioc, bio); + + ret = __submit_bio(bio); + if (queued) + bio_set_private_data(bio, ret); + } else { + ret = __submit_bio(bio); + } /* * Sort new bios into those for a lower level and those for the @@ -1073,6 +1195,33 @@ static blk_qc_t __submit_bio_noacct(struct bio *bio) return ret; } +static inline blk_qc_t __submit_bio_noacct_poll(struct bio *bio, + struct io_context *ioc) +{ + struct blk_bio_poll_ctx *pc = ioc->data; + + __submit_bio_noacct_ctx(bio, ioc); + + /* bio submissions queued to per-task poll context */ + if (READ_ONCE(pc->sq->nr_grps)) + return current->pid; + + /* swapper's pid is 0, but it can't submit poll IO for us */ + return BLK_QC_T_BIO_NONE; +} + +static inline blk_qc_t __submit_bio_noacct(struct bio *bio) +{ + struct io_context *ioc = current->io_context; + + if (ioc && ioc->data && (bio->bi_opf & REQ_HIPRI)) + return __submit_bio_noacct_poll(bio, ioc); + + __submit_bio_noacct_ctx(bio, NULL); + + return BLK_QC_T_BIO_NONE; +} + static blk_qc_t __submit_bio_noacct_mq(struct bio *bio) { struct bio_list bio_list[2] = { }; diff --git a/block/blk-ioc.c b/block/blk-ioc.c index 5574c398eff6..c1fd7c593a54 100644 --- a/block/blk-ioc.c +++ b/block/blk-ioc.c @@ -211,6 +211,9 @@ void exit_io_context(struct task_struct *task) task->io_context = NULL; task_unlock(task); + /* drain io poll submissions */ + blk_bio_poll_io_drain(ioc); + atomic_dec(&ioc->nr_tasks); put_io_context_active(ioc); } diff --git a/block/blk-mq.c b/block/blk-mq.c index 0cb88c719916..b65f2c170fb0 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3865,14 +3865,252 @@ static inline int blk_mq_poll_hctx(struct request_queue *q, return ret; } +static int blk_mq_poll_io(struct bio *bio) +{ + struct request_queue *q = bio->bi_bdev->bd_disk->queue; + blk_qc_t cookie = bio_get_private_data(bio); + int ret = 0; + + if (!bio_flagged(bio, BIO_DONE) && blk_qc_t_valid(cookie)) { + struct blk_mq_hw_ctx *hctx = + q->queue_hw_ctx[blk_qc_t_to_queue_num(cookie)]; + + ret += blk_mq_poll_hctx(q, hctx); + } + return ret; +} + +static int blk_bio_poll_and_end_io(struct bio_grp_list *grps) +{ + int ret = 0; + int i; + + /* + * Poll hw queue first. + * + * TODO: limit max poll times and make sure to not poll same + * hw queue one more time. + */ + for (i = 0; i < grps->nr_grps; i++) { + struct bio_grp_list_data *grp = &grps->head[i]; + struct bio *bio; + + if (bio_grp_list_grp_empty(grp)) + continue; + + for (bio = grp->list.head; bio; bio = bio->bi_poll) + ret += blk_mq_poll_io(bio); + } + + /* reap bios */ + for (i = 0; i < grps->nr_grps; i++) { + struct bio_grp_list_data *grp = &grps->head[i]; + struct bio *bio; + struct bio_list bl; + + if (bio_grp_list_grp_empty(grp)) + continue; + + bio_list_init(&bl); + + while ((bio = __bio_grp_list_pop(&grp->list))) { + if (bio_flagged(bio, BIO_DONE)) { + /* now recover original data */ + bio->bi_poll = grp->grp_data; + + /* clear BIO_END_BY_POLL and end me really */ + bio_clear_flag(bio, BIO_END_BY_POLL); + bio_endio(bio); + } else { + __bio_grp_list_add(&bl, bio); + } + } + __bio_grp_list_merge(&grp->list, &bl); + } + return ret; +} + +static void blk_bio_poll_pack_groups(struct bio_grp_list *grps) +{ + int i, j, k = 0; + int cnt = 0; + + for (i = grps->nr_grps - 1; i >= 0; i--) { + struct bio_grp_list_data *grp = &grps->head[i]; + struct bio_grp_list_data *hole = NULL; + + if (bio_grp_list_grp_empty(grp)) { + cnt++; + continue; + } + + for (j = k; j < i; j++) { + if (bio_grp_list_grp_empty(&grps->head[j])) { + hole = &grps->head[j]; + break; + } + } + if (hole == NULL) + break; + *hole = *grp; + cnt++; + k = j; + } + + grps->nr_grps -= cnt; +} + +#define MAX_BIO_GRPS_ON_STACK 8 +struct bio_grp_list_stack { + unsigned int max_nr_grps, nr_grps; + struct bio_grp_list_data head[MAX_BIO_GRPS_ON_STACK]; +}; + +static int blk_bio_poll_io(struct io_context *submit_ioc, + struct io_context *poll_ioc) + +{ + struct bio_grp_list_stack _bio_grps = { + .max_nr_grps = ARRAY_SIZE(_bio_grps.head), + .nr_grps = 0 + }; + struct bio_grp_list *bio_grps = (struct bio_grp_list *)&_bio_grps; + struct blk_bio_poll_ctx *submit_ctx = submit_ioc->data; + struct blk_bio_poll_ctx *poll_ctx = poll_ioc ? + poll_ioc->data : NULL; + int ret = 0; + + /* + * Move IO submission result from submission queue in submission + * context to poll queue of poll context. + */ + if (READ_ONCE(submit_ctx->sq->nr_grps) > 0) { + spin_lock(&submit_ctx->sq_lock); + bio_grp_list_move(bio_grps, submit_ctx->sq); + spin_unlock(&submit_ctx->sq_lock); + } + + /* merge new bios first, then start to poll bios from pq */ + if (poll_ctx) { + spin_lock(&poll_ctx->pq_lock); + bio_grp_list_move(poll_ctx->pq, bio_grps); + bio_grp_list_move(bio_grps, poll_ctx->pq); + spin_unlock(&poll_ctx->pq_lock); + } + + do { + ret += blk_bio_poll_and_end_io(bio_grps); + blk_bio_poll_pack_groups(bio_grps); + + if (bio_grps->nr_grps) { + /* + * move back, and keep polling until all can be + * held in either poll queue or submission queue. + */ + if (poll_ctx) { + spin_lock(&poll_ctx->pq_lock); + bio_grp_list_move(poll_ctx->pq, bio_grps); + spin_unlock(&poll_ctx->pq_lock); + } else { + spin_lock(&submit_ctx->sq_lock); + bio_grp_list_move(submit_ctx->sq, bio_grps); + spin_unlock(&submit_ctx->sq_lock); + } + } + } while (bio_grps->nr_grps > 0); + + return ret; +} + +void blk_bio_poll_io_drain(struct io_context *submit_ioc) +{ + struct blk_bio_poll_ctx *submit_ctx = submit_ioc->data; + + if (!submit_ctx) + return; + + spin_lock(&submit_ctx->sq_lock); + while (READ_ONCE(submit_ctx->sq->nr_grps) > 0) { + blk_bio_poll_and_end_io(submit_ctx->sq); + blk_bio_poll_pack_groups(submit_ctx->sq); + cpu_relax(); + } + spin_unlock(&submit_ctx->sq_lock); +} + +static bool blk_bio_ioc_valid(struct task_struct *t) +{ + if (!t) + return false; + + if (!t->io_context) + return false; + + if (!t->io_context->data) + return false; + + return true; +} + +static int __blk_bio_poll(blk_qc_t cookie) +{ + struct io_context *poll_ioc = current->io_context; + pid_t pid; + struct task_struct *submit_task; + int ret; + + pid = (pid_t)cookie; + + /* io poll often share io submission context */ + if (likely(current->pid == pid && blk_bio_ioc_valid(current))) + return blk_bio_poll_io(poll_ioc, poll_ioc); + + submit_task = find_get_task_by_vpid(pid); + if (likely(blk_bio_ioc_valid(submit_task))) + ret = blk_bio_poll_io(submit_task->io_context, poll_ioc); + else + ret = 0; + if (likely(submit_task)) + put_task_struct(submit_task); + + return ret; +} + static int blk_bio_poll(struct request_queue *q, blk_qc_t cookie, bool spin) { + long state; + + /* no need to poll */ + if (cookie == BLK_QC_T_BIO_NONE) + return 0; + /* * Create poll queue for storing poll bio and its cookie from * submission queue */ blk_create_io_poll_context(q); + state = current->state; + do { + int ret; + + ret = __blk_bio_poll(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; } @@ -3893,7 +4131,7 @@ int blk_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) || !blk_queue_poll(q)) + if (!blk_queue_poll(q) || (queue_is_mq(q) && !blk_qc_t_valid(cookie))) return 0; if (current->plug) diff --git a/block/blk.h b/block/blk.h index c1d8456656df..c0216f2e6293 100644 --- a/block/blk.h +++ b/block/blk.h @@ -381,6 +381,7 @@ struct blk_bio_poll_ctx { #define BLK_BIO_POLL_SQ_SZ 16U #define BLK_BIO_POLL_PQ_SZ (BLK_BIO_POLL_SQ_SZ * 2) +void blk_bio_poll_io_drain(struct io_context *submit_ioc); void bio_poll_ctx_alloc(struct io_context *ioc); static inline void blk_create_io_poll_context(struct request_queue *q) @@ -405,4 +406,13 @@ static inline void bio_set_private_data(struct bio *bio, unsigned int data) bio->bi_iter.bi_private_data = data; } +BIO_LIST_HELPERS(__bio_grp_list, poll); + +static inline bool bio_grp_list_grp_empty(struct bio_grp_list_data *grp) +{ + return bio_list_empty(&grp->list); +} + +void bio_grp_list_move(struct bio_grp_list *dst, struct bio_grp_list *src); + #endif /* BLK_INTERNAL_H */ diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 99160d588c2d..beaeb3729f11 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -235,7 +235,18 @@ struct bio { struct bvec_iter bi_iter; - bio_end_io_t *bi_end_io; + union { + bio_end_io_t *bi_end_io; + /* + * bio based io polling needs to track bio via bio group + * list which groups bios by their .bi_end_io, and original + * .bi_end_io is saved into the group head. Will recover + * .bi_end_io before really ending bio. BIO_END_BY_POLL + * will make sure that this bio won't be ended before + * recovering .bi_end_io. + */ + struct bio *bi_poll; + }; void *bi_private; #ifdef CONFIG_BLK_CGROUP @@ -304,6 +315,9 @@ enum { BIO_CGROUP_ACCT, /* has been accounted to a cgroup */ BIO_TRACKED, /* set if bio goes through the rq_qos path */ BIO_REMAPPED, + BIO_END_BY_POLL, /* end by blk_bio_poll() explicitly */ + /* set when bio can be ended, used for bio with BIO_END_BY_POLL */ + BIO_DONE, BIO_FLAG_LAST }; @@ -513,6 +527,8 @@ typedef unsigned int blk_qc_t; #define BLK_QC_T_NONE -1U #define BLK_QC_T_SHIFT 16 #define BLK_QC_T_INTERNAL (1U << 31) +/* only used for bio based submission, has to be defined as 0 */ +#define BLK_QC_T_BIO_NONE 0 static inline bool blk_qc_t_valid(blk_qc_t cookie) { From patchwork Mon Mar 29 15:26:19 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 12170387 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 4CCF2C433E1 for ; Mon, 29 Mar 2021 15:28:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1637261970 for ; Mon, 29 Mar 2021 15:28:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230229AbhC2P2T (ORCPT ); Mon, 29 Mar 2021 11:28:19 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:49518 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230516AbhC2P2F (ORCPT ); Mon, 29 Mar 2021 11:28:05 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617031684; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/XWBRGeLiCgYP4XRDpEtok71EzVPi94F6vd9vLonjGo=; b=GEKN2dlmbiaaxj/43UJzWposojkaDJWO7wFNfQs22TZLc7Fo69jQrHmba8AJAODApvl+DE TSLVkG75rhNpA7x+z2cnnAcCZCzmnkaXpvGgCoiA50CbLKtJlft/X+G7XJoAKy40+NBy3y ql0JuEFSryCu4ZU8UHE3XRdQ1fKbSBc= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-58-a-4fAjFkMW-prs5P8coPpQ-1; Mon, 29 Mar 2021 11:28:02 -0400 X-MC-Unique: a-4fAjFkMW-prs5P8coPpQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 1B23818C8C01; Mon, 29 Mar 2021 15:28:01 +0000 (UTC) Received: from localhost (ovpn-12-50.pek2.redhat.com [10.72.12.50]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5A8225C5DF; Mon, 29 Mar 2021 15:28:00 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Jeffle Xu , Mike Snitzer , dm-devel@redhat.com, Hannes Reinecke , Ming Lei Subject: [PATCH V4 09/12] blk-mq: limit hw queues to be polled in each blk_poll() Date: Mon, 29 Mar 2021 23:26:19 +0800 Message-Id: <20210329152622.173035-10-ming.lei@redhat.com> In-Reply-To: <20210329152622.173035-1-ming.lei@redhat.com> References: <20210329152622.173035-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Limit at most 8 queues are polled in each blk_pull(), avoid to add extra latency when queue depth is high. Signed-off-by: Ming Lei Reviewed-by: Jeffle Xu --- block/blk-mq.c | 73 ++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 53 insertions(+), 20 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index b65f2c170fb0..414f5d99d9de 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3865,32 +3865,31 @@ static inline int blk_mq_poll_hctx(struct request_queue *q, return ret; } -static int blk_mq_poll_io(struct bio *bio) +#define POLL_HCTX_MAX_CNT 8 + +static bool blk_add_unique_hctx(struct blk_mq_hw_ctx **data, int *cnt, + struct blk_mq_hw_ctx *hctx) { - struct request_queue *q = bio->bi_bdev->bd_disk->queue; - blk_qc_t cookie = bio_get_private_data(bio); - int ret = 0; + int i; - if (!bio_flagged(bio, BIO_DONE) && blk_qc_t_valid(cookie)) { - struct blk_mq_hw_ctx *hctx = - q->queue_hw_ctx[blk_qc_t_to_queue_num(cookie)]; + for (i = 0; i < *cnt; i++) { + if (data[i] == hctx) + goto exit; + } - ret += blk_mq_poll_hctx(q, hctx); + if (i < POLL_HCTX_MAX_CNT) { + data[i] = hctx; + (*cnt)++; } - return ret; + exit: + return *cnt == POLL_HCTX_MAX_CNT; } -static int blk_bio_poll_and_end_io(struct bio_grp_list *grps) +static void blk_build_poll_queues(struct bio_grp_list *grps, + struct blk_mq_hw_ctx **data, int *cnt) { - int ret = 0; int i; - /* - * Poll hw queue first. - * - * TODO: limit max poll times and make sure to not poll same - * hw queue one more time. - */ for (i = 0; i < grps->nr_grps; i++) { struct bio_grp_list_data *grp = &grps->head[i]; struct bio *bio; @@ -3898,11 +3897,29 @@ static int blk_bio_poll_and_end_io(struct bio_grp_list *grps) if (bio_grp_list_grp_empty(grp)) continue; - for (bio = grp->list.head; bio; bio = bio->bi_poll) - ret += blk_mq_poll_io(bio); + for (bio = grp->list.head; bio; bio = bio->bi_poll) { + blk_qc_t cookie; + struct blk_mq_hw_ctx *hctx; + struct request_queue *q; + + if (bio_flagged(bio, BIO_DONE)) + continue; + cookie = bio_get_private_data(bio); + if (!blk_qc_t_valid(cookie)) + continue; + + q = bio->bi_bdev->bd_disk->queue; + hctx = q->queue_hw_ctx[blk_qc_t_to_queue_num(cookie)]; + if (blk_add_unique_hctx(data, cnt, hctx)) + return; + } } +} + +static void blk_bio_poll_reap_ios(struct bio_grp_list *grps) +{ + int i; - /* reap bios */ for (i = 0; i < grps->nr_grps; i++) { struct bio_grp_list_data *grp = &grps->head[i]; struct bio *bio; @@ -3927,6 +3944,22 @@ static int blk_bio_poll_and_end_io(struct bio_grp_list *grps) } __bio_grp_list_merge(&grp->list, &bl); } +} + +static int blk_bio_poll_and_end_io(struct bio_grp_list *grps) +{ + int ret = 0; + int i; + struct blk_mq_hw_ctx *hctx[POLL_HCTX_MAX_CNT]; + int cnt = 0; + + blk_build_poll_queues(grps, hctx, &cnt); + + for (i = 0; i < cnt; i++) + ret += blk_mq_poll_hctx(hctx[i]->queue, hctx[i]); + + blk_bio_poll_reap_ios(grps); + return ret; } From patchwork Mon Mar 29 15:26:20 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 12170391 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 B2718C433E6 for ; Mon, 29 Mar 2021 15:28:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 89AEA6196C for ; Mon, 29 Mar 2021 15:28:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229479AbhC2P2U (ORCPT ); Mon, 29 Mar 2021 11:28:20 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:39393 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231379AbhC2P2I (ORCPT ); Mon, 29 Mar 2021 11:28:08 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617031688; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=+D7R0dmx1EexdXy1yf5Y6TiIr7C7M/actiCutRe5+Uw=; b=RBn0ikkcfeEL5LkwxRWgxilAdoBzsoTmdHrxrm9X0bP8oie00Q6/Bj4vlg6Ezp7GKwkCh9 hHAWd0hBTGraF26jwOBcCLo77grAUdzzrLaUYNvCVPbR0ltlxCGTaI34tO2PEqqkDxF2mT Amwg8lwjroPgfu1aAeJQvzGZ7xEYJWo= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-501-LBtM8QJPO5Gtnj3rJt5SCw-1; Mon, 29 Mar 2021 11:28:05 -0400 X-MC-Unique: LBtM8QJPO5Gtnj3rJt5SCw-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id DEFF8A0C25; Mon, 29 Mar 2021 15:28:03 +0000 (UTC) Received: from localhost (ovpn-12-50.pek2.redhat.com [10.72.12.50]) by smtp.corp.redhat.com (Postfix) with ESMTP id 24968196E3; Mon, 29 Mar 2021 15:28:02 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Jeffle Xu , Mike Snitzer , dm-devel@redhat.com, Hannes Reinecke Subject: [PATCH V4 10/12] block: add queue_to_disk() to get gendisk from request_queue Date: Mon, 29 Mar 2021 23:26:20 +0800 Message-Id: <20210329152622.173035-11-ming.lei@redhat.com> In-Reply-To: <20210329152622.173035-1-ming.lei@redhat.com> References: <20210329152622.173035-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org From: Jeffle Xu 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 Reviewed-by: Hannes Reinecke --- 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 89a01850cf12..bfab74b45f15 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -686,6 +686,8 @@ 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 Mon Mar 29 15:26:21 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 12170395 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 C8AAFC433E9 for ; Mon, 29 Mar 2021 15:28:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AB14C61994 for ; Mon, 29 Mar 2021 15:28:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231354AbhC2P2V (ORCPT ); Mon, 29 Mar 2021 11:28:21 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:53653 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231312AbhC2P2P (ORCPT ); Mon, 29 Mar 2021 11:28:15 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617031695; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Jhriek1NirfToS7eI8Q/r2pkPUKbNKEQOu9gH5WO164=; b=X1Em1a3NHoenmjD6ARZKCHF8jQ8lrwszK681cxsKzLRQXZVReDNO+U/UPe2N8rFIuNw0ph ivmwBrcBAm8fQ0YoC6EPo0tqqf4ai8q95eB30HKGA9IMz6BeMw/33sFSQaAeOJqXEI8Q4R USV4lrMp9kdYrDxY/YBW62qlwZvX2WE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-427-d58ADUwyOaGHz2Ev90G6pQ-1; Mon, 29 Mar 2021 11:28:08 -0400 X-MC-Unique: d58ADUwyOaGHz2Ev90G6pQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5BE40108BD07; Mon, 29 Mar 2021 15:28:07 +0000 (UTC) Received: from localhost (ovpn-12-50.pek2.redhat.com [10.72.12.50]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9A5111349A; Mon, 29 Mar 2021 15:28:06 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Jeffle Xu , Mike Snitzer , dm-devel@redhat.com, Hannes Reinecke Subject: [PATCH V4 11/12] block: add poll_capable method to support bio-based IO polling Date: Mon, 29 Mar 2021 23:26:21 +0800 Message-Id: <20210329152622.173035-12-ming.lei@redhat.com> In-Reply-To: <20210329152622.173035-1-ming.lei@redhat.com> References: <20210329152622.173035-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org From: Jeffle Xu 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 Reviewed-by: Hannes Reinecke --- 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 db3268d41274..c8e7e4af66cb 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 bfab74b45f15..a46f975f2a2f 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1881,6 +1881,7 @@ struct block_device_operations { int (*report_zones)(struct gendisk *, sector_t sector, unsigned int nr_zones, report_zones_cb cb, void *data); char *(*devnode)(struct gendisk *disk, umode_t *mode); + bool (*poll_capable)(struct gendisk *disk); struct module *owner; const struct pr_ops *pr_ops; }; From patchwork Mon Mar 29 15:26:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 12170397 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 D92C4C433E0 for ; Mon, 29 Mar 2021 15:29:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9FD23617ED for ; Mon, 29 Mar 2021 15:29:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231363AbhC2P2t (ORCPT ); Mon, 29 Mar 2021 11:28:49 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:24313 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231404AbhC2P2R (ORCPT ); Mon, 29 Mar 2021 11:28:17 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617031696; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=WprMeSTUBlNB0D+G5/hB14w1VWfRCDMbMSxpzet0DV8=; b=BtMDd17h5fgepGN558wqUEldEvtif5+rf4Xf2rrIsF6LIRdQiAtlkprgnVC6NJdqX9ot0l xM67qtE1G3iVywi5C3vkUk+oGDNYc5BatnDPChh5CXqxFOdUHUdGzgg8/vgJns/BGg9HYL gwgw7nbR8ufTpcjuHB3xSmLp26fqcNs= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-399-sO36VVkNOW6ELDhlNeFBrw-1; Mon, 29 Mar 2021 11:28:11 -0400 X-MC-Unique: sO36VVkNOW6ELDhlNeFBrw-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6F7C4A0C04; Mon, 29 Mar 2021 15:28:10 +0000 (UTC) Received: from localhost (ovpn-12-50.pek2.redhat.com [10.72.12.50]) by smtp.corp.redhat.com (Postfix) with ESMTP id B181F5D9F0; Mon, 29 Mar 2021 15:28:09 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Jeffle Xu , Mike Snitzer , dm-devel@redhat.com, Hannes Reinecke , Ming Lei Subject: [PATCH V4 12/12] dm: support IO polling for bio-based dm device Date: Mon, 29 Mar 2021 23:26:22 +0800 Message-Id: <20210329152622.173035-13-ming.lei@redhat.com> In-Reply-To: <20210329152622.173035-1-ming.lei@redhat.com> References: <20210329152622.173035-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org From: Jeffle Xu 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. Reviewed-by: Mike Snitzer Signed-off-by: Jeffle Xu Signed-off-by: Ming Lei Reviewed-by: Hannes Reinecke --- drivers/md/dm-table.c | 24 ++++++++++++++++++++++++ drivers/md/dm.c | 14 ++++++++++++++ include/linux/device-mapper.h | 1 + 3 files changed, 39 insertions(+) diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 95391f78b8d5..a8f3575fb118 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -1509,6 +1509,12 @@ struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector) return &t->targets[(KEYS_PER_NODE * n) + k]; } +static int device_not_poll_capable(struct dm_target *ti, struct dm_dev *dev, + sector_t start, sector_t len, void *data) +{ + return !blk_queue_poll(bdev_get_queue(dev->bdev)); +} + /* * type->iterate_devices() should be called when the sanity check needs to * iterate and check all underlying data devices. iterate_devices() will @@ -1559,6 +1565,11 @@ static int count_device(struct dm_target *ti, struct dm_dev *dev, return 0; } +int dm_table_supports_poll(struct dm_table *t) +{ + return !dm_table_any_dev_attr(t, device_not_poll_capable, NULL); +} + /* * Check whether a table has no data devices attached using each * target's iterate_devices method. @@ -2079,6 +2090,19 @@ 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 50b693d776d6..dacc988045c9 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1720,6 +1720,19 @@ static blk_qc_t dm_submit_bio(struct bio *bio) return ret; } +static bool dm_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. *---------------------------------------------------------------*/ @@ -3132,6 +3145,7 @@ static const struct pr_ops dm_pr_ops = { }; static const struct block_device_operations dm_blk_dops = { + .poll_capable = dm_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.