From patchwork Thu Jun 22 08:39:15 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qi Zheng X-Patchwork-Id: 13288546 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 8D35FEB64DB for ; Thu, 22 Jun 2023 08:42:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231352AbjFVImq (ORCPT ); Thu, 22 Jun 2023 04:42:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56318 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231300AbjFVImL (ORCPT ); Thu, 22 Jun 2023 04:42:11 -0400 Received: from out-32.mta1.migadu.com (out-32.mta1.migadu.com [95.215.58.32]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B90F526A2 for ; Thu, 22 Jun 2023 01:41:27 -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=1687423285; 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=FjncEPBmZQNKtUMkKxyWnfUd+QNedTmj64H5ENjps78=; b=lnC4EAsriqzk6Vg3PsGJ6YdZPgIBp18Lhel2S0f8vfVmaxOMpUH7w6LfdRXOcYPLlNu3I3 j/qu/8a2yrW6Gfq3DhvSuklliGWfa6l2tvkk9Ar9ygKDw9xtKuJU8ntv2Opi7E65LTv/fu oxqUNwg0dU4TV+Hlx7tn3EnVt9tgXR8= 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 12/29] mbcache: dynamically allocate the mbcache shrinker Date: Thu, 22 Jun 2023 08:39:15 +0000 Message-Id: <20230622083932.4090339-13-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-btrfs@vger.kernel.org From: Qi Zheng In preparation for implementing lockless slab shrink, we need to dynamically allocate the mbcache 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 mb_cache. Signed-off-by: Qi Zheng --- fs/mbcache.c | 39 +++++++++++++++++++++------------------ 1 file changed, 21 insertions(+), 18 deletions(-) diff --git a/fs/mbcache.c b/fs/mbcache.c index 2a4b8b549e93..fec393e55a66 100644 --- a/fs/mbcache.c +++ b/fs/mbcache.c @@ -37,7 +37,7 @@ struct mb_cache { struct list_head c_list; /* Number of entries in cache */ unsigned long c_entry_count; - struct shrinker c_shrink; + struct shrinker *c_shrink; /* Work for shrinking when the cache has too many entries */ struct work_struct c_shrink_work; }; @@ -293,8 +293,7 @@ EXPORT_SYMBOL(mb_cache_entry_touch); static unsigned long mb_cache_count(struct shrinker *shrink, struct shrink_control *sc) { - struct mb_cache *cache = container_of(shrink, struct mb_cache, - c_shrink); + struct mb_cache *cache = shrink->private_data; return cache->c_entry_count; } @@ -333,8 +332,8 @@ static unsigned long mb_cache_shrink(struct mb_cache *cache, static unsigned long mb_cache_scan(struct shrinker *shrink, struct shrink_control *sc) { - struct mb_cache *cache = container_of(shrink, struct mb_cache, - c_shrink); + struct mb_cache *cache = shrink->private_data; + return mb_cache_shrink(cache, sc->nr_to_scan); } @@ -370,26 +369,30 @@ struct mb_cache *mb_cache_create(int bucket_bits) cache->c_hash = kmalloc_array(bucket_count, sizeof(struct hlist_bl_head), GFP_KERNEL); - if (!cache->c_hash) { - kfree(cache); - goto err_out; - } + if (!cache->c_hash) + goto err_c_hash; + for (i = 0; i < bucket_count; i++) INIT_HLIST_BL_HEAD(&cache->c_hash[i]); - cache->c_shrink.count_objects = mb_cache_count; - cache->c_shrink.scan_objects = mb_cache_scan; - cache->c_shrink.seeks = DEFAULT_SEEKS; - if (register_shrinker(&cache->c_shrink, "mbcache-shrinker")) { - kfree(cache->c_hash); - kfree(cache); - goto err_out; - } + cache->c_shrink = shrinker_alloc_and_init(mb_cache_count, mb_cache_scan, + 0, DEFAULT_SEEKS, 0, cache); + if (!cache->c_shrink) + goto err_shrinker; + + if (register_shrinker(cache->c_shrink, "mbcache-shrinker")) + goto err_register; INIT_WORK(&cache->c_shrink_work, mb_cache_shrink_worker); return cache; +err_register: + shrinker_free(cache->c_shrink); +err_shrinker: + kfree(cache->c_hash); +err_c_hash: + kfree(cache); err_out: return NULL; } @@ -406,7 +409,7 @@ void mb_cache_destroy(struct mb_cache *cache) { struct mb_cache_entry *entry, *next; - unregister_shrinker(&cache->c_shrink); + unregister_and_free_shrinker(cache->c_shrink); /* * We don't bother with any locking. Cache must not be used at this