From patchwork Thu Jun 29 11:03:56 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chengming Zhou X-Patchwork-Id: 13296899 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A52E7EB64DC for ; Thu, 29 Jun 2023 11:07:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232159AbjF2LHR (ORCPT ); Thu, 29 Jun 2023 07:07:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35800 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229632AbjF2LHQ (ORCPT ); Thu, 29 Jun 2023 07:07:16 -0400 Received: from out-21.mta1.migadu.com (out-21.mta1.migadu.com [IPv6:2001:41d0:203:375::15]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 94C1F10CF for ; Thu, 29 Jun 2023 04:07:15 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1688036833; 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=dNin81+NgdWvZKUgysygT1wpEuRFau3v3obyeOkX5fM=; b=wwqEmJdrPmGhPaPCNNeah4+ETGQTleAhQTC7xostmyZuZdJychdvBYIDsi+H4x6MrfHW8p c6P2ePqkoYs95JZypBggJd7pyt64ZMEfrqpnao0izFegeXWFKgAL8UwFUZRoOWGW+V21oL hto1QBQcoDWwYWAKXB5SN1k+aLYpCkk= From: chengming.zhou@linux.dev To: axboe@kernel.dk, ming.lei@redhat.com, hch@lst.de, tj@kernel.org Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, Chengming Zhou Subject: [PATCH v2 1/4] blk-mq: use percpu csd to remote complete instead of per-rq csd Date: Thu, 29 Jun 2023 19:03:56 +0800 Message-Id: <20230629110359.1111832-2-chengming.zhou@linux.dev> In-Reply-To: <20230629110359.1111832-1-chengming.zhou@linux.dev> References: <20230629110359.1111832-1-chengming.zhou@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org From: Chengming Zhou If request need to be completed remotely, we insert it into percpu llist, and smp_call_function_single_async() if llist is empty previously. We don't need to use per-rq csd, percpu csd is enough. And the size of struct request is decreased by 24 bytes. This way is cleaner, and looks correct, given block softirq is guaranteed to be scheduled to consume the list if one new request is added to this percpu list, either smp_call_function_single_async() returns -EBUSY or 0. Signed-off-by: Chengming Zhou Reviewed-by: Ming Lei --- v2: - Change to use call_single_data_t, which avoid to use 2 cache lines for 1 csd, as suggested by Ming Lei. - Improve the commit log, the explanation is copied from Ming Lei. --- block/blk-mq.c | 12 ++++++++---- include/linux/blk-mq.h | 5 +---- 2 files changed, 9 insertions(+), 8 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index decb6ab2d508..e52200edd2b1 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -43,6 +43,7 @@ #include "blk-ioprio.h" static DEFINE_PER_CPU(struct llist_head, blk_cpu_done); +static DEFINE_PER_CPU(call_single_data_t, blk_cpu_csd); static void blk_mq_insert_request(struct request *rq, blk_insert_t flags); static void blk_mq_request_bypass_insert(struct request *rq, @@ -1156,13 +1157,13 @@ static void blk_mq_complete_send_ipi(struct request *rq) { struct llist_head *list; unsigned int cpu; + call_single_data_t *csd; cpu = rq->mq_ctx->cpu; list = &per_cpu(blk_cpu_done, cpu); - if (llist_add(&rq->ipi_list, list)) { - INIT_CSD(&rq->csd, __blk_mq_complete_request_remote, rq); - smp_call_function_single_async(cpu, &rq->csd); - } + csd = &per_cpu(blk_cpu_csd, cpu); + if (llist_add(&rq->ipi_list, list)) + smp_call_function_single_async(cpu, csd); } static void blk_mq_raise_softirq(struct request *rq) @@ -4796,6 +4797,9 @@ static int __init blk_mq_init(void) for_each_possible_cpu(i) init_llist_head(&per_cpu(blk_cpu_done, i)); + for_each_possible_cpu(i) + INIT_CSD(&per_cpu(blk_cpu_csd, i), + __blk_mq_complete_request_remote, NULL); open_softirq(BLOCK_SOFTIRQ, blk_done_softirq); cpuhp_setup_state_nocalls(CPUHP_BLOCK_SOFTIRQ_DEAD, diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index f401067ac03a..070551197c0e 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -182,10 +182,7 @@ struct request { rq_end_io_fn *saved_end_io; } flush; - union { - struct __call_single_data csd; - u64 fifo_time; - }; + u64 fifo_time; /* * completion callback. From patchwork Thu Jun 29 11:03:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chengming Zhou X-Patchwork-Id: 13296900 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 57B14EB64D9 for ; Thu, 29 Jun 2023 11:07:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232163AbjF2LHZ (ORCPT ); Thu, 29 Jun 2023 07:07:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35838 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232168AbjF2LHU (ORCPT ); Thu, 29 Jun 2023 07:07:20 -0400 Received: from out-18.mta1.migadu.com (out-18.mta1.migadu.com [IPv6:2001:41d0:203:375::12]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5DB151FE3 for ; Thu, 29 Jun 2023 04:07:18 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1688036836; 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=MamvVjI1jeXw3Kjngjhi6g/DzhtYYjp3x8kVfhCNxDw=; b=gLJaqTIYrWNNdCKmHcyxDtI7XwL0mz5l3b8romo8vPvm3yG7ob3tBombjqyDMsDaGTHxQb +kHsA+GFLKWIs8pAEGKOvbbzIVfb/nq9my9qTM5RpeenzPBIiyKWjry3rp6b7NL5Rz8VSt 15Y7uKyzuXr8dJjMaVC2yBqu+gsqTXE= From: chengming.zhou@linux.dev To: axboe@kernel.dk, ming.lei@redhat.com, hch@lst.de, tj@kernel.org Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, Chengming Zhou Subject: [PATCH v2 2/4] blk-flush: count inflight flush_data requests Date: Thu, 29 Jun 2023 19:03:57 +0800 Message-Id: <20230629110359.1111832-3-chengming.zhou@linux.dev> In-Reply-To: <20230629110359.1111832-1-chengming.zhou@linux.dev> References: <20230629110359.1111832-1-chengming.zhou@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org From: Chengming Zhou The flush state machine use a double list to link all inflight flush_data requests, to avoid issuing separate post-flushes for these flush_data requests which shared PREFLUSH. So we can't reuse rq->queuelist, this is why we need rq->flush.list In preparation of the next patch that reuse rq->queuelist for flush state machine, we change the double linked list to unsigned long counter, which count all inflight flush_data requests. This is ok since we only need to know if there is any inflight flush_data request, so unsigned long counter is good. Signed-off-by: Chengming Zhou Reviewed-by: Ming Lei Reviewed-by: Christoph Hellwig --- block/blk-flush.c | 9 +++++---- block/blk.h | 5 ++--- 2 files changed, 7 insertions(+), 7 deletions(-) diff --git a/block/blk-flush.c b/block/blk-flush.c index dba392cf22be..bb7adfc2a5da 100644 --- a/block/blk-flush.c +++ b/block/blk-flush.c @@ -187,7 +187,8 @@ static void blk_flush_complete_seq(struct request *rq, break; case REQ_FSEQ_DATA: - list_move_tail(&rq->flush.list, &fq->flush_data_in_flight); + list_del_init(&rq->flush.list); + fq->flush_data_in_flight++; spin_lock(&q->requeue_lock); list_add_tail(&rq->queuelist, &q->flush_list); spin_unlock(&q->requeue_lock); @@ -299,7 +300,7 @@ static void blk_kick_flush(struct request_queue *q, struct blk_flush_queue *fq, return; /* C2 and C3 */ - if (!list_empty(&fq->flush_data_in_flight) && + if (fq->flush_data_in_flight && time_before(jiffies, fq->flush_pending_since + FLUSH_PENDING_TIMEOUT)) return; @@ -374,6 +375,7 @@ static enum rq_end_io_ret mq_flush_data_end_io(struct request *rq, * the comment in flush_end_io(). */ spin_lock_irqsave(&fq->mq_flush_lock, flags); + fq->flush_data_in_flight--; blk_flush_complete_seq(rq, fq, REQ_FSEQ_DATA, error); spin_unlock_irqrestore(&fq->mq_flush_lock, flags); @@ -445,7 +447,7 @@ bool blk_insert_flush(struct request *rq) blk_rq_init_flush(rq); rq->flush.seq |= REQ_FSEQ_POSTFLUSH; spin_lock_irq(&fq->mq_flush_lock); - list_move_tail(&rq->flush.list, &fq->flush_data_in_flight); + fq->flush_data_in_flight++; spin_unlock_irq(&fq->mq_flush_lock); return false; default: @@ -496,7 +498,6 @@ struct blk_flush_queue *blk_alloc_flush_queue(int node, int cmd_size, INIT_LIST_HEAD(&fq->flush_queue[0]); INIT_LIST_HEAD(&fq->flush_queue[1]); - INIT_LIST_HEAD(&fq->flush_data_in_flight); return fq; diff --git a/block/blk.h b/block/blk.h index 608c5dcc516b..686712e13835 100644 --- a/block/blk.h +++ b/block/blk.h @@ -15,15 +15,14 @@ struct elevator_type; extern struct dentry *blk_debugfs_root; struct blk_flush_queue { + spinlock_t mq_flush_lock; unsigned int flush_pending_idx:1; unsigned int flush_running_idx:1; blk_status_t rq_status; unsigned long flush_pending_since; struct list_head flush_queue[2]; - struct list_head flush_data_in_flight; + unsigned long flush_data_in_flight; struct request *flush_rq; - - spinlock_t mq_flush_lock; }; bool is_flush_rq(struct request *req); From patchwork Thu Jun 29 11:03:58 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chengming Zhou X-Patchwork-Id: 13296901 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EE706EB64D9 for ; Thu, 29 Jun 2023 11:07:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232215AbjF2LH0 (ORCPT ); Thu, 29 Jun 2023 07:07:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35842 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232196AbjF2LHW (ORCPT ); Thu, 29 Jun 2023 07:07:22 -0400 Received: from out-11.mta1.migadu.com (out-11.mta1.migadu.com [IPv6:2001:41d0:203:375::b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6C032E72 for ; Thu, 29 Jun 2023 04:07:20 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1688036839; 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=hdKaqogn/I3BFaAaWb1R9T3dUmGgvZb8Wo54xKMjRbQ=; b=Silj4FteQiWcNtz1G5WBCi+kTB4VQErkWfbaa7zSefq9ofMpCw2enGXVGq1vM3jhZTLgFn NEpX1/qmz+ji/HU91h7L4sqAwSCrqyD+NBNJCJer5WZU0VA0mzEShHlAz39RAbTxvuJ6UF SZ1nj4EpaWnZkhJ282cITiMpW021VZQ= From: chengming.zhou@linux.dev To: axboe@kernel.dk, ming.lei@redhat.com, hch@lst.de, tj@kernel.org Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, Chengming Zhou Subject: [PATCH v2 3/4] blk-flush: reuse rq queuelist in flush state machine Date: Thu, 29 Jun 2023 19:03:58 +0800 Message-Id: <20230629110359.1111832-4-chengming.zhou@linux.dev> In-Reply-To: <20230629110359.1111832-1-chengming.zhou@linux.dev> References: <20230629110359.1111832-1-chengming.zhou@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org From: Chengming Zhou Since we don't need to maintain inflight flush_data requests list anymore, we can reuse rq->queuelist for flush pending list. This patch decrease the size of struct request by 16 bytes. Signed-off-by: Chengming Zhou Reviewed-by: Christoph Hellwig --- block/blk-flush.c | 12 +++++------- include/linux/blk-mq.h | 1 - 2 files changed, 5 insertions(+), 8 deletions(-) diff --git a/block/blk-flush.c b/block/blk-flush.c index bb7adfc2a5da..81588edbe8b0 100644 --- a/block/blk-flush.c +++ b/block/blk-flush.c @@ -183,14 +183,13 @@ static void blk_flush_complete_seq(struct request *rq, /* queue for flush */ if (list_empty(pending)) fq->flush_pending_since = jiffies; - list_move_tail(&rq->flush.list, pending); + list_move_tail(&rq->queuelist, pending); break; case REQ_FSEQ_DATA: - list_del_init(&rq->flush.list); fq->flush_data_in_flight++; spin_lock(&q->requeue_lock); - list_add_tail(&rq->queuelist, &q->flush_list); + list_move_tail(&rq->queuelist, &q->flush_list); spin_unlock(&q->requeue_lock); blk_mq_kick_requeue_list(q); break; @@ -202,7 +201,7 @@ static void blk_flush_complete_seq(struct request *rq, * flush data request completion path. Restore @rq for * normal completion and end it. */ - list_del_init(&rq->flush.list); + list_del_init(&rq->queuelist); blk_flush_restore_request(rq); blk_mq_end_request(rq, error); break; @@ -258,7 +257,7 @@ static enum rq_end_io_ret flush_end_io(struct request *flush_rq, fq->flush_running_idx ^= 1; /* and push the waiting requests to the next stage */ - list_for_each_entry_safe(rq, n, running, flush.list) { + list_for_each_entry_safe(rq, n, running, queuelist) { unsigned int seq = blk_flush_cur_seq(rq); BUG_ON(seq != REQ_FSEQ_PREFLUSH && seq != REQ_FSEQ_POSTFLUSH); @@ -292,7 +291,7 @@ static void blk_kick_flush(struct request_queue *q, struct blk_flush_queue *fq, { struct list_head *pending = &fq->flush_queue[fq->flush_pending_idx]; struct request *first_rq = - list_first_entry(pending, struct request, flush.list); + list_first_entry(pending, struct request, queuelist); struct request *flush_rq = fq->flush_rq; /* C1 described at the top of this file */ @@ -386,7 +385,6 @@ static enum rq_end_io_ret mq_flush_data_end_io(struct request *rq, static void blk_rq_init_flush(struct request *rq) { rq->flush.seq = 0; - INIT_LIST_HEAD(&rq->flush.list); rq->rq_flags |= RQF_FLUSH_SEQ; rq->flush.saved_end_io = rq->end_io; /* Usually NULL */ rq->end_io = mq_flush_data_end_io; diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 070551197c0e..96644d6f8d18 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -178,7 +178,6 @@ struct request { struct { unsigned int seq; - struct list_head list; rq_end_io_fn *saved_end_io; } flush; From patchwork Thu Jun 29 11:03:59 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chengming Zhou X-Patchwork-Id: 13296902 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 266D8C001B1 for ; Thu, 29 Jun 2023 11:07:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232039AbjF2LH2 (ORCPT ); Thu, 29 Jun 2023 07:07:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35906 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232177AbjF2LHZ (ORCPT ); Thu, 29 Jun 2023 07:07:25 -0400 Received: from out-24.mta1.migadu.com (out-24.mta1.migadu.com [95.215.58.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3975D1FE8 for ; Thu, 29 Jun 2023 04:07:23 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1688036842; 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=/O8YJWAa7A//A8YJ1hLAuWA8H/d3IRDfJMQYLuFl59Q=; b=mbIzMFKmGOLPlHTie0bZkFzRR4kKsmNBsTYTIAcXDY9PhKLh+AWN83tEAps+QrlCmHpQJ5 6vPVir4H9Ri7Ue7A0rX45a+10TN8gVkVcHKOdW31Bm1xjWYh2rKJU5FdRDZn+3xBXxdoKu lTL8df0btTRLK09OBxfpmKmt+c9Wkm4= From: chengming.zhou@linux.dev To: axboe@kernel.dk, ming.lei@redhat.com, hch@lst.de, tj@kernel.org Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, Chengming Zhou Subject: [PATCH v2 4/4] blk-mq: delete unused completion_data in struct request Date: Thu, 29 Jun 2023 19:03:59 +0800 Message-Id: <20230629110359.1111832-5-chengming.zhou@linux.dev> In-Reply-To: <20230629110359.1111832-1-chengming.zhou@linux.dev> References: <20230629110359.1111832-1-chengming.zhou@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org From: Chengming Zhou After global search, I found "completion_data" in struct request is not used anywhere, so just clean it up by the way. Signed-off-by: Chengming Zhou Reviewed-by: Christoph Hellwig --- include/linux/blk-mq.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 96644d6f8d18..ab790eba5fcf 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -158,13 +158,11 @@ struct request { /* * The rb_node is only used inside the io scheduler, requests - * are pruned when moved to the dispatch queue. So let the - * completion_data share space with the rb_node. + * are pruned when moved to the dispatch queue. */ union { struct rb_node rb_node; /* sort/lookup */ struct bio_vec special_vec; - void *completion_data; }; /*