From mboxrd@z Thu Jan 1 00:00:00 1970 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4B9FAC433EF for ; Wed, 15 Jun 2022 08:58:37 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id DB6176B0071; Wed, 15 Jun 2022 04:58:36 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D65E86B0072; Wed, 15 Jun 2022 04:58:36 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C2D786B0073; Wed, 15 Jun 2022 04:58:36 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id B38BD6B0071 for ; Wed, 15 Jun 2022 04:58:36 -0400 (EDT) Received: from smtpin24.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay12.hostedemail.com (Postfix) with ESMTP id 91985120268 for ; Wed, 15 Jun 2022 08:58:36 +0000 (UTC) X-FDA: 79579869432.24.B5330F1 Received: from mail-lf1-f47.google.com (mail-lf1-f47.google.com [209.85.167.47]) by imf11.hostedemail.com (Postfix) with ESMTP id 4343E40086 for ; Wed, 15 Jun 2022 08:58:36 +0000 (UTC) Received: by mail-lf1-f47.google.com with SMTP id w20so17825283lfa.11 for ; Wed, 15 Jun 2022 01:58:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=YJrquJD+yWQFne/J/19SMMhbGp5M+QEOAu37o1AhNAA=; b=WMRSrpMOmpoafabiWjDDIeuA3xMWBIcaqigjlUnHATSRayX90Bqze2kjD60E30r5pd Fwf8kaAe6PmfFCDXkGlBXXncuqVUdh9oaeW3jKkaXwT0MteMTgEbt3Q7LR8xEh8NPXvp ATKAGgQUfkQM6pxE0L3R6Fvq3u8vA2naFPwU8bcCb5ByHusZmGnBgVNEqAejeyAnQZZ5 1Bqwg04omL41Lrz3qV7umt9105daiKLgCXxS8vdLTJmyJMh2e7gSetHC3MG6WNMLmmaz 4G3KJYX9XT224Y5eTfLIx12rDgjIlhU0JVahKbiUy2g9FplxWReoIdmP7pyoKXuJTust OVxQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=YJrquJD+yWQFne/J/19SMMhbGp5M+QEOAu37o1AhNAA=; b=qNEfiqICfIcTrHOsgbRXtnRY7NPqrSiY0Cu4lZXdXfm5+CuAW/AZCD3CdW6ygtwxPy XaIp7t3kwbK3shfNw8TbPEau6cGxhWd2eIvAWelq5/KkzlSzTPys+vyVTvxQcqKT7rp/ mAgdArFbyrcY2cktJXxJ4tptUkeIGcslQM3ZSXeF2I3iG1KH4In7y/rxzudKzLW7fi6z q6Q+yOoq57YeCiqOUbNzuWn/c/UBA+30qInZA11DDDZH2O2CcM/8PEinHxnOa1IHptAk DepWHqSrQQz5i4YcwjcgEE/bsSOnkkoHEyadAu6hC7K+gzgMU5q/jlYb2gQKxK48KXKg 67Dg== X-Gm-Message-State: AJIora/HbHd3HWCCId5mBahDkU+YoXrCw9gOLc5WMRwr/DiOuF13dq3l vPWX7dT54z1rN7Tpqi5h/aC007ZmRMKcwOoeETM= X-Google-Smtp-Source: AGRyM1sGHf2L4J+YkwRxx2Bu8JTMes7eyyFHbYxOCnTYClF6Wl8rexsy5O+64SdUNWwSQJPN3HVFN/MEaxS0Jq4f2BA= X-Received: by 2002:a05:6512:1050:b0:47d:c714:10ba with SMTP id c16-20020a056512105000b0047dc71410bamr5524327lfb.165.1655283513046; Wed, 15 Jun 2022 01:58:33 -0700 (PDT) MIME-Version: 1.0 References: <1645174105-31224-1-git-send-email-huangzhaoyang@gmail.com> <6862cdff-189e-619b-3c87-7dce6b45475f@suse.cz> In-Reply-To: <6862cdff-189e-619b-3c87-7dce6b45475f@suse.cz> From: Zhaoyang Huang Date: Wed, 15 Jun 2022 16:58:03 +0800 Message-ID: Subject: Re: [RFC PATCH] block: set bdi congested when no tag available To: Vlastimil Babka Cc: Jens Axboe , "Martin K. Petersen" , Ming Lei , Hannes Reinecke , Bart Van Assche , Zhaoyang Huang , LKML , Andrew Morton , "open list:MEMORY MANAGEMENT" , Mel Gorman Content-Type: text/plain; charset="UTF-8" ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1655283516; a=rsa-sha256; cv=none; b=P3HSK8iK9oMtVlRZMXjyRtvvfji57KPvlna8RvFfZSj7DCHoLL691rHRnu31ZItOwrVVDz GhAtqlmYbqtmgXwSHdYCB2bjbzfiGDHUYiv0LKiDdQ34oSjEHwSC7JAdqkfFfrCOwRuwQS XT4H9sILCRFxt0vXzM3qljcKevuXhO8= ARC-Authentication-Results: i=1; imf11.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=WMRSrpMO; spf=pass (imf11.hostedemail.com: domain of huangzhaoyang@gmail.com designates 209.85.167.47 as permitted sender) smtp.mailfrom=huangzhaoyang@gmail.com; dmarc=pass (policy=none) header.from=gmail.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1655283516; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=YJrquJD+yWQFne/J/19SMMhbGp5M+QEOAu37o1AhNAA=; b=6AzdyTL9sU+gKT0SXKiAmo3iXclOxAuCiCH/vtiTfaU8BgSZTqisoXUwx9OoglN9TeBMjI EVdPenOcvQkt0sNXSMneZ7CmXfN+PGHxS767OQN4HkbpnePPUVk/odxKqcrT9Gs4TsPB2S tF+iPLPgov9jyXMVlIj+Hv94vx42P9g= X-Rspam-User: X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 4343E40086 X-Stat-Signature: p7dsn4qrktgxijyfuhm8n56b8d65bepe Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=WMRSrpMO; spf=pass (imf11.hostedemail.com: domain of huangzhaoyang@gmail.com designates 209.85.167.47 as permitted sender) smtp.mailfrom=huangzhaoyang@gmail.com; dmarc=pass (policy=none) header.from=gmail.com X-HE-Tag: 1655283516-457917 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Mar 9, 2022 at 7:50 PM Vlastimil Babka wrote: > > On 3/9/22 08:40, Zhaoyang Huang wrote: > > 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 blk-mq design. > > Hm I thought Mel removed the direct reclaim throttling based on bdi > congestion in his series [1]. Maybe block layers has other uses (I have no > idea), for tracking congestion, that should be mentioned instead? > > [1] > https://lore.kernel.org/all/20211022144651.19914-1-mgorman@techsingularity.net/ > As my understanding, the above patch change suspending on bdi congested for a given interval to be woken up by finish of request or bio. This patch is not against above one, which add one more scenario for setting bdi as congested. > > > > 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..bd1e520 100644 > > --- a/block/blk-mq-tag.c > > +++ b/block/blk-mq-tag.c > > @@ -11,6 +11,7 @@ > > > > #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 != BLK_MQ_NO_TAG) > > goto found_tag; > > > > - 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; > > + } > > > > ws = 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; > > } > > > > +static bool blk_mq_has_free_tags(struct blk_mq_tags *tags) > > +{ > > + if (!tags) > > + return true; > > + > > + return sbitmap_any_bit_clear(&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 = tag - tags->nr_reserved_tags; > > > > 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); > > > > #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); > > > > +bool sbitmap_any_bit_clear(const struct sbitmap *sb) > > +{ > > + unsigned int i; > > + > > + for (i = 0; i < sb->map_nr; i++) { > > + const struct sbitmap_word *word = &sb->map[i]; > > + unsigned long mask = word->word & ~word->cleared; > > + unsigned long ret; > > + > > + ret = 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 = 0; >