From nobody Sat Jun 27 23:13:21 2026 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 18C3FC433EF for ; Fri, 18 Feb 2022 08:48:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232812AbiBRItK (ORCPT ); Fri, 18 Feb 2022 03:49:10 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:40768 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232069AbiBRItJ (ORCPT ); Fri, 18 Feb 2022 03:49:09 -0500 Received: from mail-pl1-x62f.google.com (mail-pl1-x62f.google.com [IPv6:2607:f8b0:4864:20::62f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8A4AE2B3542 for ; Fri, 18 Feb 2022 00:48:52 -0800 (PST) Received: by mail-pl1-x62f.google.com with SMTP id u12so6620459plf.13 for ; Fri, 18 Feb 2022 00:48:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:subject:date:message-id; bh=UBoCfCt3Y6PWGhQUApUNw771uw0a8IEHtaftJDZ7myg=; b=I0aAUBIweoBxJ1jI4FL7cCZKt3zwfVBBL6vD2KVaxliEyqa7RYjpSS7IGOb0Z7rWrM iaeGGGG39yev7rkjtpdm7G11Dyiqn8SGMxl/P+WgAq3ZUEwYLojMAlv435ybTqsRyZA7 dShgT7TVRrIC0DY1Qeh4iqY9bXqURoPdZg4ZfMzIKzC36qJejCU/SuzG2MdqLFOQKyB1 5U3ZyX06eY2PtOMVs4VpkJrpsclNVfFVqrnT5roXlY9fjZf1NrzZLrp4N3jhBEoJm4Ds 3hES+Vi7JQt/0+k+OboRy+OQZwKVa/5xCzLGAtcItp00iRFw6vbth+0UE4f4r9vY3OwH 1NXg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:subject:date:message-id; bh=UBoCfCt3Y6PWGhQUApUNw771uw0a8IEHtaftJDZ7myg=; b=D1Dgu+KfJ2mDWtCI3d1k2twxw/P/02IrSqpt8FGwcPSQqQhWlyR+tESx8KujR3hxCn JSoNAue/HE4twb1YZukI7kd/mLwNh3arY/6SDiokxq/OciYFH73F3BCEasnXa+qZNG5B PnzUqmt20ZAVx7u14ZT5ahy9nKnIv1HBgGBcTYdw68ULX6PeTyyWMyIK6Tl7B/mY73CE 58Qn6Hvb30RbjLSyIplhbvX3QZL79NtebT3uZUrW12ZNtNnNEEHVmMVbL+p6tu+r/ltr LLIlGTbL26TNZxhYv7e9WUTJnUHmoRek/3LPzP7Er6qQyD6wgeQs9kvCYPYyfhlI++rv ZXbQ== X-Gm-Message-State: AOAM530xTB1jNfWI6rQ4KPMO/8sNwJpOAKU1XgnqYWb60Ylvb2BKBHIy PREmQjmn/t3LSGYCFVX0WS0= X-Google-Smtp-Source: ABdhPJy4al8z6M1b8hySqSRd1n9l/F41nqACMIgx+J5bk6fSVGb9nmlzjNKJStngmv965T4meAakJQ== X-Received: by 2002:a17:902:dac1:b0:14d:c0f7:3227 with SMTP id q1-20020a170902dac100b0014dc0f73227mr6434800plx.70.1645174132010; Fri, 18 Feb 2022 00:48:52 -0800 (PST) Received: from bj03382pcu.spreadtrum.com ([117.18.48.102]) by smtp.gmail.com with ESMTPSA id l16sm2139155pjy.14.2022.02.18.00.48.49 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Fri, 18 Feb 2022 00:48:51 -0800 (PST) From: Huangzhaoyang To: Jens Axboe , "Martin K. Petersen" , Ming Lei , Hannes Reinecke , Bart Van Assche , Zhaoyang Huang , linux-kernel@vger.kernel.org Subject: [RFC PATCH] block: set bdi congested when no tag available Date: Fri, 18 Feb 2022 16:48:25 +0800 Message-Id: <1645174105-31224-1-git-send-email-huangzhaoyang@gmail.com> X-Mailer: git-send-email 1.7.9.5 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" From: Zhaoyang Huang In previous version, block layer will set bdi to be congested when get_request fail, which may throttle direct_reclaim. Move them back under current design. Signed-off-by: Zhaoyang Huang --- block/blk-mq-tag.c | 18 +++++++++++++++++- include/linux/sbitmap.h | 1 + lib/sbitmap.c | 17 +++++++++++++++++ 3 files changed, 35 insertions(+), 1 deletion(-) diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index 995336a..abb0685 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -11,6 +11,7 @@ =20 #include #include +#include #include "blk.h" #include "blk-mq.h" #include "blk-mq-sched.h" @@ -126,8 +127,11 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *= data) if (tag !=3D BLK_MQ_NO_TAG) goto found_tag; =20 - if (data->flags & BLK_MQ_REQ_NOWAIT) + if (data->flags & BLK_MQ_REQ_NOWAIT) { + set_bdi_congested(data->q->disk->bdi,BLK_RW_SYNC); + set_bdi_congested(data->q->disk->bdi,BLK_RW_ASYNC); return BLK_MQ_NO_TAG; + } =20 ws =3D bt_wait_ptr(bt, data->hctx); do { @@ -193,9 +197,21 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *= data) return tag + tag_offset; } =20 +static bool blk_mq_has_free_tags(struct blk_mq_tags *tags) +{ + if (!tags) + return true; + + return sbitmap_any_bit_set(&tags->bitmap_tags.sb); +} + void blk_mq_put_tag(struct blk_mq_tags *tags, struct blk_mq_ctx *ctx, unsigned int tag) { + if (!blk_mq_has_free_tags(tags)) { + clear_bdi_congested(ctx->queue->disk->bdi, BLK_RW_SYNC); + clear_bdi_congested(ctx->queue->disk->bdi, BLK_RW_ASYNC); + } if (!blk_mq_tag_is_reserved(tags, tag)) { const int real_tag =3D tag - tags->nr_reserved_tags; =20 diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h index 4a6ff27..30a5553 100644 --- a/include/linux/sbitmap.h +++ b/include/linux/sbitmap.h @@ -210,6 +210,7 @@ static inline void sbitmap_free(struct sbitmap *sb) * Return: true if any bit in the bitmap is set, false otherwise. */ bool sbitmap_any_bit_set(const struct sbitmap *sb); +bool sbitmap_any_bit_clear(const struct sbitmap *sb); =20 #define SB_NR_TO_INDEX(sb, bitnr) ((bitnr) >> (sb)->shift) #define SB_NR_TO_BIT(sb, bitnr) ((bitnr) & ((1U << (sb)->shift) - 1U)) diff --git a/lib/sbitmap.c b/lib/sbitmap.c index 2709ab8..baa30d8 100644 --- a/lib/sbitmap.c +++ b/lib/sbitmap.c @@ -309,6 +309,23 @@ bool sbitmap_any_bit_set(const struct sbitmap *sb) } EXPORT_SYMBOL_GPL(sbitmap_any_bit_set); =20 +bool sbitmap_any_bit_clear(const struct sbitmap *sb) +{ + unsigned int i; + + for (i =3D 0; i < sb->map_nr; i++) { + const struct sbitmap_word *word =3D &sb->map[i]; + unsigned long mask =3D word->word & ~word->cleared; + unsigned long ret; + + ret =3D find_first_zero_bit(&mask, word->depth); + if (ret < word->depth) + return true; + } + return false; +} +EXPORT_SYMBOL_GPL(sbitmap_any_bit_clear); + static unsigned int __sbitmap_weight(const struct sbitmap *sb, bool set) { unsigned int i, weight =3D 0; --=20 1.9.1