From nobody Tue Dec 16 21:49:23 2025 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 715ECEE49A6 for ; Thu, 24 Aug 2023 03:50:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239893AbjHXDt5 (ORCPT ); Wed, 23 Aug 2023 23:49:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48130 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239626AbjHXDsI (ORCPT ); Wed, 23 Aug 2023 23:48:08 -0400 Received: from mail-pf1-x434.google.com (mail-pf1-x434.google.com [IPv6:2607:f8b0:4864:20::434]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 89AD41BD9 for ; Wed, 23 Aug 2023 20:47:15 -0700 (PDT) Received: by mail-pf1-x434.google.com with SMTP id d2e1a72fcca58-68a32506e90so1062588b3a.1 for ; Wed, 23 Aug 2023 20:47:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1692848831; x=1693453631; 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=DERoMXizB4tQD41l3IFVDcK/UoRWwvr52IaKs7kkWyE=; b=l3iIlNkEM9G3Cc/znNYH0hjfEGMFScoGFsPDxRlIYD6Nl4f8r8Y4ffur08X22M57wD rIlSmJrfx+3UpxggfbKcjCE4Dvgc5I/LQBD+OIaafLzWd7xdzc3eeSUn3jYMqVJn93em 0W1GznsolsuflbV+uszoAiXaDHnfJ+tiKXIpWvpYd/Ij4f6UXGCJcJb4Hscr3UTl0p3b LW0D56skk4nR8+fdc5jfeMFs4SDrmcbSIrL0BJ5k/5kJZyOenUt/nJGwsdGpkJqafAVm Vnc6/t5P1QbupbAmEIByI7s5m2r7bE1g7Fg9vHnXnyXTIzG01/FAXBjLAVWjh1RgylMp uG3A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1692848831; x=1693453631; 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=DERoMXizB4tQD41l3IFVDcK/UoRWwvr52IaKs7kkWyE=; b=W8qbCM9c3WIr3G1UblR+znUJYYAP9/XigdZVAjPYkaDbeEYr1gDjfKQCITfZKOYxVh JUnmJuSA3JLOI3nJ7VALEI91Plk7mTlcOChIhQfusjzJ3Oeu56FlOgq065WDa1UudkYN wKUafEuXbnxV+zX8dsr5JVLtFfbNlpIShlxMtErdZKGnM6hXlPx7k6eG+T49rzrImr10 LLyzs3Puhanx5stqi6EJhJOYBjw65JvRAInxmUPIYewPr7nv6UDm88Md2zXL5MUYzPe+ lc/QnYLykU3rx7abF6D0jMKMO+gWTs06/61lIvRA30hIF0eQwPBYy4WhhJepLYatJOIG Hx4w== X-Gm-Message-State: AOJu0YxtIdbjsXDgUnvhKm1tGOcxdLsfmkgs86fidH5cmxubiqI84Ogq TkPkapuJuIFKpd/LJlx4QNf9Ww== X-Google-Smtp-Source: AGHT+IFa4D13lTfF9qI4lzhNEmw+/ylikA2tFRh1ZHmSW0TIoxErglnaTpv3xvyiYGMU4coQffhatQ== X-Received: by 2002:a05:6a00:3107:b0:68a:4bf9:3b21 with SMTP id bi7-20020a056a00310700b0068a4bf93b21mr11172345pfb.0.1692848831711; Wed, 23 Aug 2023 20:47:11 -0700 (PDT) Received: from C02DW0BEMD6R.bytedance.net ([203.208.167.146]) by smtp.gmail.com with ESMTPSA id t6-20020a63b246000000b005579f12a238sm10533157pgo.86.2023.08.23.20.47.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 23 Aug 2023 20:47:11 -0700 (PDT) From: Qi Zheng To: akpm@linux-foundation.org, david@fromorbit.com, tkhai@ya.ru, vbabka@suse.cz, roman.gushchin@linux.dev, djwong@kernel.org, brauner@kernel.org, paulmck@kernel.org, tytso@mit.edu, steven.price@arm.com, cel@kernel.org, senozhatsky@chromium.org, yujie.liu@intel.com, gregkh@linuxfoundation.org, muchun.song@linux.dev Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, Qi Zheng , Muchun Song , Alasdair Kergon , Mike Snitzer , dm-devel@redhat.com Subject: [PATCH v5 23/45] dm: dynamically allocate the dm-bufio shrinker Date: Thu, 24 Aug 2023 11:42:42 +0800 Message-Id: <20230824034304.37411-24-zhengqi.arch@bytedance.com> X-Mailer: git-send-email 2.24.3 (Apple Git-128) In-Reply-To: <20230824034304.37411-1-zhengqi.arch@bytedance.com> References: <20230824034304.37411-1-zhengqi.arch@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" In preparation for implementing lockless slab shrink, use new APIs to dynamically allocate the dm-bufio shrinker, so that it can be freed asynchronously via RCU. Then it doesn't need to wait for RCU read-side critical section when releasing the struct dm_bufio_client. Signed-off-by: Qi Zheng Reviewed-by: Muchun Song CC: Alasdair Kergon CC: Mike Snitzer CC: dm-devel@redhat.com --- drivers/md/dm-bufio.c | 28 +++++++++++++++++----------- 1 file changed, 17 insertions(+), 11 deletions(-) diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c index bc309e41d074..62eb27639c9b 100644 --- a/drivers/md/dm-bufio.c +++ b/drivers/md/dm-bufio.c @@ -963,7 +963,7 @@ struct dm_bufio_client { =20 sector_t start; =20 - struct shrinker shrinker; + struct shrinker *shrinker; struct work_struct shrink_work; atomic_long_t need_shrink; =20 @@ -2368,7 +2368,7 @@ static unsigned long dm_bufio_shrink_scan(struct shri= nker *shrink, struct shrink { struct dm_bufio_client *c; =20 - c =3D container_of(shrink, struct dm_bufio_client, shrinker); + c =3D shrink->private_data; atomic_long_add(sc->nr_to_scan, &c->need_shrink); queue_work(dm_bufio_wq, &c->shrink_work); =20 @@ -2377,7 +2377,7 @@ static unsigned long dm_bufio_shrink_scan(struct shri= nker *shrink, struct shrink =20 static unsigned long dm_bufio_shrink_count(struct shrinker *shrink, struct= shrink_control *sc) { - struct dm_bufio_client *c =3D container_of(shrink, struct dm_bufio_client= , shrinker); + struct dm_bufio_client *c =3D shrink->private_data; unsigned long count =3D cache_total(&c->cache); unsigned long retain_target =3D get_retain_buffers(c); unsigned long queued_for_cleanup =3D atomic_long_read(&c->need_shrink); @@ -2490,14 +2490,20 @@ struct dm_bufio_client *dm_bufio_client_create(stru= ct block_device *bdev, unsign INIT_WORK(&c->shrink_work, shrink_work); atomic_long_set(&c->need_shrink, 0); =20 - c->shrinker.count_objects =3D dm_bufio_shrink_count; - c->shrinker.scan_objects =3D dm_bufio_shrink_scan; - c->shrinker.seeks =3D 1; - c->shrinker.batch =3D 0; - r =3D register_shrinker(&c->shrinker, "dm-bufio:(%u:%u)", - MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev)); - if (r) + c->shrinker =3D shrinker_alloc(0, "dm-bufio:(%u:%u)", + MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev)); + if (!c->shrinker) { + r =3D -ENOMEM; goto bad; + } + + c->shrinker->count_objects =3D dm_bufio_shrink_count; + c->shrinker->scan_objects =3D dm_bufio_shrink_scan; + c->shrinker->seeks =3D 1; + c->shrinker->batch =3D 0; + c->shrinker->private_data =3D c; + + shrinker_register(c->shrinker); =20 mutex_lock(&dm_bufio_clients_lock); dm_bufio_client_count++; @@ -2537,7 +2543,7 @@ void dm_bufio_client_destroy(struct dm_bufio_client *= c) =20 drop_buffers(c); =20 - unregister_shrinker(&c->shrinker); + shrinker_free(c->shrinker); flush_work(&c->shrink_work); =20 mutex_lock(&dm_bufio_clients_lock); --=20 2.30.2