From patchwork Fri Oct 21 10:34:05 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Begunkov X-Patchwork-Id: 13014587 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 AB463C4321E for ; Fri, 21 Oct 2022 10:36:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230003AbiJUKg0 (ORCPT ); Fri, 21 Oct 2022 06:36:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42998 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229940AbiJUKgY (ORCPT ); Fri, 21 Oct 2022 06:36:24 -0400 Received: from mail-wr1-x429.google.com (mail-wr1-x429.google.com [IPv6:2a00:1450:4864:20::429]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A5F71245E9F; Fri, 21 Oct 2022 03:36:17 -0700 (PDT) Received: by mail-wr1-x429.google.com with SMTP id a14so1331458wru.5; Fri, 21 Oct 2022 03:36:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=erLTlmyi83dM0fdrryvYn9BtXwohwFqw9KpHLk/mAwk=; b=GV/LMIDHpWiYWvuunCnNMCfMciupdhaB5W5535rM/tXU0gpxVIvM+yzcu3C9SR1/Fx D8VmDEZeN9TzxytOkxU8Kco6zYiEbxeUK+jFfP8jBaXEKdNSJG596vY6ufysfC76/C6d 1BtLT5SC70uCaSMgXnra6nsp43gD6HXiIeaek2Xig9VTryLdFsZGRV5LhRBjILmtt03H 0yRmvaYyyxagUklmTYxuIByuAympM67kQ8x9bMkcgi3OCzGqVv+mEh79UYyQCIj25jtM Di6Oiz5wr0IlNj0B9/L23ruHDVRX///hOp1G6Xyj26gUMP7z2Z7q4eZ+1f6yA2U4dt1H QD1g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=erLTlmyi83dM0fdrryvYn9BtXwohwFqw9KpHLk/mAwk=; b=FPsJdRAP41XhIigGFN5D4RNaLeBQLSUG4znMl2QYtQ+s1lZspH/mYqvmVESmcnh2gW n5p0c9/BvqobdjPETBSEAChRdOmyAz99qk0GrgrOE/TtTTPAIfrD8bwfoouFQzCF+JJ6 oGLmrZmj/jZJyKiG1KwESV0w8qSLYaPtxjVYrAj4Z33CtD8SYwWudpzdu7O3dFD692OP rgtGTAUuQnbwJRC4KTE9yz5o9FbcdtdTcq0euc1JdRtF6/UxFoEBsGYxWh7RWX24Qf6Y 9M31ED4k0NQOArZHma9tSNTrSpVRdcnzfd7VpvQrAi8iBOFOs8cwQ5Mcyf/begSaSZd8 utyA== X-Gm-Message-State: ACrzQf2pZSFNgoTFbwMw+cohudUv3FeLyQBXoo9iFdE2X0YI/yfP1N9a wfw3IaeOSKqQWJEKVlgXD7c= X-Google-Smtp-Source: AMsMyM6IZwIxhNDxvaK8eVMfkZvkdycOYUwNTkS1F/+DSZalqlMTnpEZBhtwQWQFdTwFz8BqF01EqQ== X-Received: by 2002:a05:6000:184e:b0:22e:4649:b3c9 with SMTP id c14-20020a056000184e00b0022e4649b3c9mr12323125wri.671.1666348575442; Fri, 21 Oct 2022 03:36:15 -0700 (PDT) Received: from 127.0.0.1localhost.com ([2620:10d:c092:600::2:f27e]) by smtp.gmail.com with ESMTPSA id e14-20020a5d65ce000000b0022abcc1e3cesm18544759wrw.116.2022.10.21.03.36.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 21 Oct 2022 03:36:14 -0700 (PDT) From: Pavel Begunkov To: Jens Axboe , linux-block@vger.kernel.org Cc: io-uring@vger.kernel.org, linux-kernel@vger.kernel.org, Christoph Hellwig , Pavel Begunkov Subject: [PATCH for-next v3 1/3] bio: split pcpu cache part of bio_put into a helper Date: Fri, 21 Oct 2022 11:34:05 +0100 Message-Id: <5cbfcc454cd9ecda250332b393f282d5742ba987.1666347703.git.asml.silence@gmail.com> X-Mailer: git-send-email 2.38.0 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Extract a helper out of bio_put for recycling into percpu caches. It's a preparation patch without functional changes. Signed-off-by: Pavel Begunkov --- block/bio.c | 38 +++++++++++++++++++++++++------------- 1 file changed, 25 insertions(+), 13 deletions(-) diff --git a/block/bio.c b/block/bio.c index 0a14af923738..7a573e0f5f52 100644 --- a/block/bio.c +++ b/block/bio.c @@ -725,6 +725,28 @@ static void bio_alloc_cache_destroy(struct bio_set *bs) bs->cache = NULL; } +static inline void bio_put_percpu_cache(struct bio *bio) +{ + struct bio_alloc_cache *cache; + + cache = per_cpu_ptr(bio->bi_pool->cache, get_cpu()); + bio_uninit(bio); + + if ((bio->bi_opf & REQ_POLLED) && !WARN_ON_ONCE(in_interrupt())) { + bio->bi_next = cache->free_list; + cache->free_list = bio; + cache->nr++; + } else { + put_cpu(); + bio_free(bio); + return; + } + + if (cache->nr > ALLOC_CACHE_MAX + ALLOC_CACHE_SLACK) + bio_alloc_cache_prune(cache, ALLOC_CACHE_SLACK); + put_cpu(); +} + /** * bio_put - release a reference to a bio * @bio: bio to release reference to @@ -740,20 +762,10 @@ void bio_put(struct bio *bio) if (!atomic_dec_and_test(&bio->__bi_cnt)) return; } - - if ((bio->bi_opf & REQ_ALLOC_CACHE) && !WARN_ON_ONCE(in_interrupt())) { - struct bio_alloc_cache *cache; - - bio_uninit(bio); - cache = per_cpu_ptr(bio->bi_pool->cache, get_cpu()); - bio->bi_next = cache->free_list; - cache->free_list = bio; - if (++cache->nr > ALLOC_CACHE_MAX + ALLOC_CACHE_SLACK) - bio_alloc_cache_prune(cache, ALLOC_CACHE_SLACK); - put_cpu(); - } else { + if (bio->bi_opf & REQ_ALLOC_CACHE) + bio_put_percpu_cache(bio); + else bio_free(bio); - } } EXPORT_SYMBOL(bio_put); From patchwork Fri Oct 21 10:34:06 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Begunkov X-Patchwork-Id: 13014586 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 08B10C43219 for ; Fri, 21 Oct 2022 10:36:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229987AbiJUKgZ (ORCPT ); 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Fri, 21 Oct 2022 03:36:16 -0700 (PDT) From: Pavel Begunkov To: Jens Axboe , linux-block@vger.kernel.org Cc: io-uring@vger.kernel.org, linux-kernel@vger.kernel.org, Christoph Hellwig , Pavel Begunkov Subject: [PATCH for-next v3 2/3] block/bio: add pcpu caching for non-polling bio_put Date: Fri, 21 Oct 2022 11:34:06 +0100 Message-Id: <4bf4e1716600b929866c13b4c15dcf94f11f9f3f.1666347703.git.asml.silence@gmail.com> X-Mailer: git-send-email 2.38.0 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org This patch extends REQ_ALLOC_CACHE to IRQ completions, whenever currently it's only limited to iopoll. Instead of guarding the list with irq toggling on alloc, which is expensive, it keeps an additional irq-safe list from which bios are spliced in batches to ammortise overhead. On the put side it toggles irqs, but in many cases they're already disabled and so cheap. Signed-off-by: Pavel Begunkov --- block/bio.c | 63 +++++++++++++++++++++++++++++++++++++++++++---------- 1 file changed, 51 insertions(+), 12 deletions(-) diff --git a/block/bio.c b/block/bio.c index 7a573e0f5f52..f7c57352f306 100644 --- a/block/bio.c +++ b/block/bio.c @@ -25,9 +25,15 @@ #include "blk-rq-qos.h" #include "blk-cgroup.h" +#define ALLOC_CACHE_THRESHOLD 16 +#define ALLOC_CACHE_SLACK 64 +#define ALLOC_CACHE_MAX 512 + struct bio_alloc_cache { struct bio *free_list; + struct bio *free_list_irq; unsigned int nr; + unsigned int nr_irq; }; static struct biovec_slab { @@ -408,6 +414,22 @@ static void punt_bios_to_rescuer(struct bio_set *bs) queue_work(bs->rescue_workqueue, &bs->rescue_work); } +static void bio_alloc_irq_cache_splice(struct bio_alloc_cache *cache) +{ + unsigned long flags; + + /* cache->free_list must be empty */ + if (WARN_ON_ONCE(cache->free_list)) + return; + + local_irq_save(flags); + cache->free_list = cache->free_list_irq; + cache->free_list_irq = NULL; + cache->nr += cache->nr_irq; + cache->nr_irq = 0; + local_irq_restore(flags); +} + static struct bio *bio_alloc_percpu_cache(struct block_device *bdev, unsigned short nr_vecs, blk_opf_t opf, gfp_t gfp, struct bio_set *bs) @@ -416,9 +438,13 @@ static struct bio *bio_alloc_percpu_cache(struct block_device *bdev, struct bio *bio; cache = per_cpu_ptr(bs->cache, get_cpu()); - if (!cache->free_list) { - put_cpu(); - return NULL; + if (!cache->free_list && + READ_ONCE(cache->nr_irq) >= ALLOC_CACHE_THRESHOLD) { + bio_alloc_irq_cache_splice(cache); + if (!cache->free_list) { + put_cpu(); + return NULL; + } } bio = cache->free_list; cache->free_list = bio->bi_next; @@ -676,11 +702,8 @@ void guard_bio_eod(struct bio *bio) bio_truncate(bio, maxsector << 9); } -#define ALLOC_CACHE_MAX 512 -#define ALLOC_CACHE_SLACK 64 - -static void bio_alloc_cache_prune(struct bio_alloc_cache *cache, - unsigned int nr) +static int __bio_alloc_cache_prune(struct bio_alloc_cache *cache, + unsigned int nr) { unsigned int i = 0; struct bio *bio; @@ -692,6 +715,17 @@ static void bio_alloc_cache_prune(struct bio_alloc_cache *cache, if (++i == nr) break; } + return i; +} + +static void bio_alloc_cache_prune(struct bio_alloc_cache *cache, + unsigned int nr) +{ + nr -= __bio_alloc_cache_prune(cache, nr); + if (!READ_ONCE(cache->free_list)) { + bio_alloc_irq_cache_splice(cache); + __bio_alloc_cache_prune(cache, nr); + } } static int bio_cpu_dead(unsigned int cpu, struct hlist_node *node) @@ -737,12 +771,17 @@ static inline void bio_put_percpu_cache(struct bio *bio) cache->free_list = bio; cache->nr++; } else { - put_cpu(); - bio_free(bio); - return; + unsigned long flags; + + local_irq_save(flags); + bio->bi_next = cache->free_list_irq; + cache->free_list_irq = bio; + cache->nr_irq++; + local_irq_restore(flags); } - if (cache->nr > ALLOC_CACHE_MAX + ALLOC_CACHE_SLACK) + if (READ_ONCE(cache->nr_irq) + cache->nr > + ALLOC_CACHE_MAX + ALLOC_CACHE_SLACK) bio_alloc_cache_prune(cache, ALLOC_CACHE_SLACK); put_cpu(); } From patchwork Fri Oct 21 10:34:07 2022 Content-Type: text/plain; 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Fri, 21 Oct 2022 03:36:18 -0700 (PDT) Received: from 127.0.0.1localhost.com ([2620:10d:c092:600::2:f27e]) by smtp.gmail.com with ESMTPSA id e14-20020a5d65ce000000b0022abcc1e3cesm18544759wrw.116.2022.10.21.03.36.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 21 Oct 2022 03:36:17 -0700 (PDT) From: Pavel Begunkov To: Jens Axboe , linux-block@vger.kernel.org Cc: io-uring@vger.kernel.org, linux-kernel@vger.kernel.org, Christoph Hellwig , Pavel Begunkov Subject: [PATCH for-next v3 3/3] io_uring/rw: enable bio caches for IRQ rw Date: Fri, 21 Oct 2022 11:34:07 +0100 Message-Id: X-Mailer: git-send-email 2.38.0 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Now we can use IOCB_ALLOC_CACHE not only for iopoll'ed reads/write but also for normal IRQ driven I/O. Signed-off-by: Pavel Begunkov --- io_uring/rw.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/io_uring/rw.c b/io_uring/rw.c index a25cd44cd415..009ed489cfa0 100644 --- a/io_uring/rw.c +++ b/io_uring/rw.c @@ -647,6 +647,7 @@ static int io_rw_init_file(struct io_kiocb *req, fmode_t mode) ret = kiocb_set_rw_flags(kiocb, rw->flags); if (unlikely(ret)) return ret; + kiocb->ki_flags |= IOCB_ALLOC_CACHE; /* * If the file is marked O_NONBLOCK, still allow retry for it if it @@ -662,7 +663,7 @@ static int io_rw_init_file(struct io_kiocb *req, fmode_t mode) return -EOPNOTSUPP; kiocb->private = NULL; - kiocb->ki_flags |= IOCB_HIPRI | IOCB_ALLOC_CACHE; + kiocb->ki_flags |= IOCB_HIPRI; kiocb->ki_complete = io_complete_rw_iopoll; req->iopoll_completed = 0; } else {