From patchwork Thu Jun 22 08:39:09 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qi Zheng X-Patchwork-Id: 13288491 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 CDCA7EB64DB for ; Thu, 22 Jun 2023 08:41:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231150AbjFVIlX (ORCPT ); Thu, 22 Jun 2023 04:41:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56518 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231225AbjFVIlE (ORCPT ); Thu, 22 Jun 2023 04:41:04 -0400 Received: from out-37.mta1.migadu.com (out-37.mta1.migadu.com [IPv6:2001:41d0:203:375::25]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1CE7426A6 for ; Thu, 22 Jun 2023 01:40:45 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1687423243; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=y3F0rUfKL2Xn8vIcW/xqhQA76/McTb+Ba5wKVW4y6Eg=; b=SZzQmrgVrr0a7kU9rsMmAszGVDK8bckX7bBVvxfPSHWQYejPEvXLZ2HPRkk+tKQrS23erf SuGqFnRsYjeusCXlNlT1ZT5Owe6S80DA/2VI0ueZ+krAGTceisdq13YNha7j9xlWXYO5kC 5nufnpLwSbmgxVLa1H9hFaeIYeAfjGs= 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 Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, dm-devel@redhat.com, linux-raid@vger.kernel.org, linux-bcache@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-nfs@vger.kernel.org, linux-xfs@vger.kernel.org, linux-btrfs@vger.kernel.org, Qi Zheng Subject: [PATCH 06/29] dm: dynamically allocate the dm-bufio shrinker Date: Thu, 22 Jun 2023 08:39:09 +0000 Message-Id: <20230622083932.4090339-7-qi.zheng@linux.dev> In-Reply-To: <20230622083932.4090339-1-qi.zheng@linux.dev> References: <20230622083932.4090339-1-qi.zheng@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: Qi Zheng In preparation for implementing lockless slab shrink, we need to dynamically allocate the dm-bufio shrinker, so that it can be freed asynchronously using kfree_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 --- drivers/md/dm-bufio.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c index eea977662e81..9472470d456d 100644 --- a/drivers/md/dm-bufio.c +++ b/drivers/md/dm-bufio.c @@ -963,7 +963,7 @@ struct dm_bufio_client { sector_t start; - struct shrinker shrinker; + struct shrinker *shrinker; struct work_struct shrink_work; atomic_long_t need_shrink; @@ -2385,7 +2385,7 @@ static unsigned long dm_bufio_shrink_scan(struct shrinker *shrink, struct shrink { struct dm_bufio_client *c; - c = container_of(shrink, struct dm_bufio_client, shrinker); + c = shrink->private_data; atomic_long_add(sc->nr_to_scan, &c->need_shrink); queue_work(dm_bufio_wq, &c->shrink_work); @@ -2394,7 +2394,7 @@ static unsigned long dm_bufio_shrink_scan(struct shrinker *shrink, struct shrink static unsigned long dm_bufio_shrink_count(struct shrinker *shrink, struct shrink_control *sc) { - struct dm_bufio_client *c = container_of(shrink, struct dm_bufio_client, shrinker); + struct dm_bufio_client *c = shrink->private_data; unsigned long count = cache_total(&c->cache); unsigned long retain_target = get_retain_buffers(c); unsigned long queued_for_cleanup = atomic_long_read(&c->need_shrink); @@ -2507,14 +2507,15 @@ struct dm_bufio_client *dm_bufio_client_create(struct block_device *bdev, unsign INIT_WORK(&c->shrink_work, shrink_work); atomic_long_set(&c->need_shrink, 0); - c->shrinker.count_objects = dm_bufio_shrink_count; - c->shrinker.scan_objects = dm_bufio_shrink_scan; - c->shrinker.seeks = 1; - c->shrinker.batch = 0; - r = register_shrinker(&c->shrinker, "dm-bufio:(%u:%u)", + c->shrinker = shrinker_alloc_and_init(dm_bufio_shrink_count, + dm_bufio_shrink_scan, 0, 1, 0, c); + if (!c->shrinker) + goto bad; + + r = register_shrinker(c->shrinker, "dm-bufio:(%u:%u)", MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev)); if (r) - goto bad; + goto bad_shrinker; mutex_lock(&dm_bufio_clients_lock); dm_bufio_client_count++; @@ -2524,6 +2525,8 @@ struct dm_bufio_client *dm_bufio_client_create(struct block_device *bdev, unsign return c; +bad_shrinker: + shrinker_free(c->shrinker); bad: while (!list_empty(&c->reserved_buffers)) { struct dm_buffer *b = list_to_buffer(c->reserved_buffers.next); @@ -2554,7 +2557,7 @@ void dm_bufio_client_destroy(struct dm_bufio_client *c) drop_buffers(c); - unregister_shrinker(&c->shrinker); + unregister_and_free_shrinker(c->shrinker); flush_work(&c->shrink_work); mutex_lock(&dm_bufio_clients_lock);