From patchwork Wed Oct 20 19:00:48 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Begunkov X-Patchwork-Id: 12573117 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 92C19C433F5 for ; Wed, 20 Oct 2021 19:01:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 754F16121E for ; Wed, 20 Oct 2021 19:01:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231462AbhJTTDS (ORCPT ); Wed, 20 Oct 2021 15:03:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58408 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231485AbhJTTDO (ORCPT ); Wed, 20 Oct 2021 15:03:14 -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 1729BC06161C for ; Wed, 20 Oct 2021 12:01:00 -0700 (PDT) Received: by mail-wr1-x429.google.com with SMTP id r18so167281wrg.6 for ; Wed, 20 Oct 2021 12:01:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=jieLNTWmzrvLHzQZ3McWX3OLp16MhU3QtUbl4LNofiE=; b=ICNNmSZC0z1QFIo3+zfUIFL9M5OKZERToiGngwwDjkbnSBWJySNFagH7FV1Bv47Npb QcDqSzqnnAE4z0RrxmTSFmup5FKmqijLAyX90N6WGNPOWeXA/+/rIX5ayf63m2LCe36W rZmfAl1QnLZv6oNOurVExzRe21nZxwNzhefbOdTCn0Wyhw2YjDlUosMhepynaGgXM4XT cwJYwS7zSWYEJO0vi7KQK/0uiViKLhzO+P5bGVlRanvQ6RRUbiZFMshNfd6AWdFtH6wT 2yi77XG1Zw5Z7VEPJ0qyyf/q9OYuuIfMrdU77DidjhNJZ36tjrFLzmGqBpkcjKph3gsg NOzw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=jieLNTWmzrvLHzQZ3McWX3OLp16MhU3QtUbl4LNofiE=; b=g4l3iJ5YV1n9ZWk+63ZEPMLjbt1tETbV4lzn3c5xSZBgI3Aeat95+Y7M6mE9M3i9X5 uIsiQFgdCFg+Dk9FCp7wDz4dJoUiWJxmyRBdvp4z/fR85Cl6q1haiiWk0dD51qSPXZUP 9Z/bViZTMlIQhEHq4KNHxJN4bPGWUuONLNCknu4DrKQEC56IH5riAGkkXHtekO7qOsBH iSdm/+1YvNDnuRvky43RUdDE7K53AXG0kW9Wq7k+ImWFb0u00a9F2HQljVMVwHk50CUW PuCEyF8WeEZ8wbAy8BqqkKt753bfmjQp9UcTtqOpm0R0wZKjeq/XKLr89mHIIkn850Kd Tt3Q== X-Gm-Message-State: AOAM531DamaCU/uS7YUxzoSj7JmPpDmPeFh8svl+spDpC1t3cfQpXUB2 GqOYgD8yZaQsGt/JbeV/Bukw2Xq9vxHBGw== X-Google-Smtp-Source: ABdhPJwzXru6U8FURPjsyw4EyCb7WBWGZJdkTlPi+xaGNO8CPgnAEUvLGyX4j+fubHtbAmJIBDSSOw== X-Received: by 2002:adf:9791:: with SMTP id s17mr1269466wrb.122.1634756458283; Wed, 20 Oct 2021 12:00:58 -0700 (PDT) Received: from 127.0.0.1localhost ([185.69.145.206]) by smtp.gmail.com with ESMTPSA id j11sm2743880wmi.24.2021.10.20.12.00.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Oct 2021 12:00:57 -0700 (PDT) From: Pavel Begunkov To: linux-block@vger.kernel.org Cc: Jens Axboe , Pavel Begunkov , Christoph Hellwig Subject: [PATCH 1/3] block: optimise boundary blkdev_read_iter's checks Date: Wed, 20 Oct 2021 20:00:48 +0100 Message-Id: X-Mailer: git-send-email 2.33.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Combine pos and len checks and mark unlikely. Also, don't reexpand if it's not truncated. Reviewed-by: Christoph Hellwig Signed-off-by: Pavel Begunkov --- block/fops.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) diff --git a/block/fops.c b/block/fops.c index 21d25ee0e4bf..8f733c919ed1 100644 --- a/block/fops.c +++ b/block/fops.c @@ -503,17 +503,20 @@ static ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to) size_t shorted = 0; ssize_t ret; - if (pos >= size) - return 0; - - size -= pos; - if (iov_iter_count(to) > size) { - shorted = iov_iter_count(to) - size; - iov_iter_truncate(to, size); + if (unlikely(pos + iov_iter_count(to) > size)) { + if (pos >= size) + return 0; + size -= pos; + if (iov_iter_count(to) > size) { + shorted = iov_iter_count(to) - size; + iov_iter_truncate(to, size); + } } ret = generic_file_read_iter(iocb, to); - iov_iter_reexpand(to, iov_iter_count(to) + shorted); + + if (unlikely(shorted)) + iov_iter_reexpand(to, iov_iter_count(to) + shorted); return ret; } From patchwork Wed Oct 20 19:00:49 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Begunkov X-Patchwork-Id: 12573123 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 134A7C433FE for ; Wed, 20 Oct 2021 19:01:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EC7DA61212 for ; Wed, 20 Oct 2021 19:01:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231460AbhJTTDS (ORCPT ); Wed, 20 Oct 2021 15:03:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58414 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231512AbhJTTDQ (ORCPT ); Wed, 20 Oct 2021 15:03:16 -0400 Received: from mail-wr1-x435.google.com (mail-wr1-x435.google.com [IPv6:2a00:1450:4864:20::435]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 87CEEC06161C for ; Wed, 20 Oct 2021 12:01:01 -0700 (PDT) Received: by mail-wr1-x435.google.com with SMTP id r10so327553wra.12 for ; Wed, 20 Oct 2021 12:01:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=NtkUFXEZ3cCtmtJBjgq+OZhnXnQWqbS57zg+x9RTvH0=; b=NTu0maTFIBGFbB2rt4KHid6OO6mmPc7RGqllfYz4qfd+e3t5Cmx6+oIKxukYYsUbCb C/zcUoCiWQX1FzFOh5M7L4bbQrXUQ2m595/mjlBB6s8axr2svIG34S1RuFUSqnvPGSFR aB50hxTkKNoxpdspaey1lJHsAaDGdCRbiCfvXlLMn0W5Qc7LVAQjQk2zmqx6F509+uXu 0g/wonGIbnKK39GFvLD1aztJLoXageA0wZfGzOiBqZxlZdCtMpG4GRnwcLAuFJF5M3Mp pHLYWrHuViTol3L3KPSv2O8CVkNwwxxUuAHM16ljojlRITkZepGqbvoRJJPMU3GoRxeP 1W3w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=NtkUFXEZ3cCtmtJBjgq+OZhnXnQWqbS57zg+x9RTvH0=; b=OBCOA3DfMmDYbMVdH4VxNzUgNrjZ+A92VZ5Jh9DiDQW9B26/ooguGV2cH28g2UfLRS dh1I5a80RJIOAoCJdMOQO973No1jxYVz2Kwf2BLfGZ7HGrfgJ5j3X4DCGETpSXNcM0n5 d2fOMo7/cMcB/Eq07B8SSJuLWlCsKSxTC49PETvfmoaVLyilGVPJPmqHCYaigSLiOow4 WRl7k+xy/s2rk2EiA5keXmtHRyCh9NYT24RfusxAYe9rgYycqIIJj6rbWm8QO3ZZdxva OK2hdD+HfOHhqzZgnttroqBb9Fy/hdDKSqSjh1M06vTZlt0jLNeipUOV3U+1qOmCHDCu +c6A== X-Gm-Message-State: AOAM531BDb58xdgQ6PV6j90xy6tW58jChLqR5uyPP++JKylHziBptA8o qeQJZrfUipQWSMJjCOIXtfQhfalC5m47Jw== X-Google-Smtp-Source: ABdhPJxQwqG5Qz/w813/VdFLyRwHM1VVsAT8p8TQrN3+kgHBDUurrwFmCOPXLqL9yCrQuaewh6yCSA== X-Received: by 2002:a5d:4dd1:: with SMTP id f17mr1272018wru.226.1634756459400; Wed, 20 Oct 2021 12:00:59 -0700 (PDT) Received: from 127.0.0.1localhost ([185.69.145.206]) by smtp.gmail.com with ESMTPSA id j11sm2743880wmi.24.2021.10.20.12.00.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Oct 2021 12:00:59 -0700 (PDT) From: Pavel Begunkov To: linux-block@vger.kernel.org Cc: Jens Axboe , Pavel Begunkov Subject: [PATCH 2/3] block: clean up blk_mq_submit_bio() merging Date: Wed, 20 Oct 2021 20:00:49 +0100 Message-Id: X-Mailer: git-send-email 2.33.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Combine blk_mq_sched_bio_merge() and blk_attempt_plug_merge() under a common if, so we don't check it twice. Signed-off-by: Pavel Begunkov Reviewed-by: Christoph Hellwig --- block/blk-mq-sched.c | 2 +- block/blk-mq-sched.h | 12 +----------- block/blk-mq.c | 15 +++++++-------- 3 files changed, 9 insertions(+), 20 deletions(-) diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index e85b7556b096..5b259fdea794 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -361,7 +361,7 @@ void blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx) } } -bool __blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio, +bool blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio, unsigned int nr_segs) { struct elevator_queue *e = q->elevator; diff --git a/block/blk-mq-sched.h b/block/blk-mq-sched.h index 98836106b25f..25d1034952b6 100644 --- a/block/blk-mq-sched.h +++ b/block/blk-mq-sched.h @@ -12,7 +12,7 @@ void blk_mq_sched_assign_ioc(struct request *rq); bool blk_mq_sched_try_merge(struct request_queue *q, struct bio *bio, unsigned int nr_segs, struct request **merged_request); -bool __blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio, +bool blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio, unsigned int nr_segs); bool blk_mq_sched_try_insert_merge(struct request_queue *q, struct request *rq, struct list_head *free); @@ -42,16 +42,6 @@ static inline bool bio_mergeable(struct bio *bio) return !(bio->bi_opf & REQ_NOMERGE_FLAGS); } -static inline bool -blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio, - unsigned int nr_segs) -{ - if (blk_queue_nomerges(q) || !bio_mergeable(bio)) - return false; - - return __blk_mq_sched_bio_merge(q, bio, nr_segs); -} - static inline bool blk_mq_sched_allow_merge(struct request_queue *q, struct request *rq, struct bio *bio) diff --git a/block/blk-mq.c b/block/blk-mq.c index a71aeed7b987..f159d007a015 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2481,7 +2481,6 @@ void blk_mq_submit_bio(struct bio *bio) { struct request_queue *q = bdev_get_queue(bio->bi_bdev); const int is_sync = op_is_sync(bio->bi_opf); - const int is_flush_fua = op_is_flush(bio->bi_opf); struct request *rq; struct blk_plug *plug; bool same_queue_rq = false; @@ -2495,12 +2494,12 @@ void blk_mq_submit_bio(struct bio *bio) if (!bio_integrity_prep(bio)) goto queue_exit; - if (!is_flush_fua && !blk_queue_nomerges(q) && - blk_attempt_plug_merge(q, bio, nr_segs, &same_queue_rq)) - goto queue_exit; - - if (blk_mq_sched_bio_merge(q, bio, nr_segs)) - goto queue_exit; + if (!blk_queue_nomerges(q) && bio_mergeable(bio)) { + if (blk_attempt_plug_merge(q, bio, nr_segs, &same_queue_rq)) + goto queue_exit; + if (blk_mq_sched_bio_merge(q, bio, nr_segs)) + goto queue_exit; + } rq_qos_throttle(q, bio); @@ -2543,7 +2542,7 @@ void blk_mq_submit_bio(struct bio *bio) return; } - if (is_flush_fua && blk_insert_flush(rq)) + if (op_is_flush(bio->bi_opf) && blk_insert_flush(rq)) return; if (plug && (q->nr_hw_queues == 1 || From patchwork Wed Oct 20 19:00:50 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Begunkov X-Patchwork-Id: 12573121 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 53817C4332F for ; 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Wed, 20 Oct 2021 12:01:01 -0700 (PDT) Received: from 127.0.0.1localhost ([185.69.145.206]) by smtp.gmail.com with ESMTPSA id j11sm2743880wmi.24.2021.10.20.12.00.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Oct 2021 12:01:00 -0700 (PDT) From: Pavel Begunkov To: linux-block@vger.kernel.org Cc: Jens Axboe , Pavel Begunkov Subject: [PATCH 3/3] block: convert fops.c magic constants to SHIFT_SECTOR Date: Wed, 20 Oct 2021 20:00:50 +0100 Message-Id: <068782b9f7e97569fb59a99529b23bb17ea4c5e2.1634755800.git.asml.silence@gmail.com> X-Mailer: git-send-email 2.33.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Don't use shifting by a magic number 9 but replace with a more descriptive SHIFT_SECTOR. Signed-off-by: Pavel Begunkov Reviewed-by: Christoph Hellwig --- block/fops.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/block/fops.c b/block/fops.c index 8f733c919ed1..396537598e3e 100644 --- a/block/fops.c +++ b/block/fops.c @@ -76,7 +76,7 @@ static ssize_t __blkdev_direct_IO_simple(struct kiocb *iocb, bio_init(&bio, vecs, nr_pages); bio_set_dev(&bio, bdev); - bio.bi_iter.bi_sector = pos >> 9; + bio.bi_iter.bi_sector = pos >> SECTOR_SHIFT; bio.bi_write_hint = iocb->ki_hint; bio.bi_private = current; bio.bi_end_io = blkdev_bio_end_io_simple; @@ -225,7 +225,7 @@ static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, for (;;) { bio_set_dev(bio, bdev); - bio->bi_iter.bi_sector = pos >> 9; + bio->bi_iter.bi_sector = pos >> SECTOR_SHIFT; bio->bi_write_hint = iocb->ki_hint; bio->bi_private = dio; bio->bi_end_io = blkdev_bio_end_io; @@ -565,16 +565,18 @@ static long blkdev_fallocate(struct file *file, int mode, loff_t start, switch (mode) { case FALLOC_FL_ZERO_RANGE: case FALLOC_FL_ZERO_RANGE | FALLOC_FL_KEEP_SIZE: - error = blkdev_issue_zeroout(bdev, start >> 9, len >> 9, - GFP_KERNEL, BLKDEV_ZERO_NOUNMAP); + error = blkdev_issue_zeroout(bdev, start >> SECTOR_SHIFT, + len >> SECTOR_SHIFT, GFP_KERNEL, + BLKDEV_ZERO_NOUNMAP); break; case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE: - error = blkdev_issue_zeroout(bdev, start >> 9, len >> 9, - GFP_KERNEL, BLKDEV_ZERO_NOFALLBACK); + error = blkdev_issue_zeroout(bdev, start >> SECTOR_SHIFT, + len >> SECTOR_SHIFT, GFP_KERNEL, + BLKDEV_ZERO_NOFALLBACK); break; case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE | FALLOC_FL_NO_HIDE_STALE: - error = blkdev_issue_discard(bdev, start >> 9, len >> 9, - GFP_KERNEL, 0); + error = blkdev_issue_discard(bdev, start >> SECTOR_SHIFT, + len >> SECTOR_SHIFT, GFP_KERNEL, 0); break; default: error = -EOPNOTSUPP;