From patchwork Thu Jun 22 08:53:29 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qi Zheng X-Patchwork-Id: 13288774 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 7C2ACC0015E for ; Thu, 22 Jun 2023 09:04:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231953AbjFVJEb (ORCPT ); Thu, 22 Jun 2023 05:04:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48356 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231923AbjFVJDt (ORCPT ); Thu, 22 Jun 2023 05:03:49 -0400 Received: from mail-pg1-x533.google.com (mail-pg1-x533.google.com [IPv6:2607:f8b0:4864:20::533]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0646C2126 for ; Thu, 22 Jun 2023 01:57:41 -0700 (PDT) Received: by mail-pg1-x533.google.com with SMTP id 41be03b00d2f7-54fd4a7ce25so1096462a12.0 for ; Thu, 22 Jun 2023 01:57:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1687424227; x=1690016227; 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=ZsvVWwvjCNbIpzLWR+JMbRdqcPMoA6IncSRNtrMJjtk=; b=btQFnTi1+Jxgpt9ZEv6SV1CxbtEwEnpYQ1WSSwhfGLNNoz+3LZU80wQIeDEMGJinhi 8+hFjjrmI0Ti2weoui+1nba3fuqZZ6jN3eQN4e+CjSeo0Ggyrqg3j3GGKdGsxTGtEKKB 6n4ntOH8ClqO9PsI9RmJeFYa/h0xYT0vefdwMfx1z83TBiR/mTSXCJDkn82jEtfe964Z +W5pu2WQm5/BmUewzteVLri/ASv79HUROzRO9GvLtgUyAJkwQyVDE/hnKFhVeWh3zZR/ QE/dybVozXXKkm+aMId69JeSrmobjvQPBxgZrNjMENKTPWKUy1hHiQ4+Qa8p1f7rRS3j Hymg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1687424227; x=1690016227; 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=ZsvVWwvjCNbIpzLWR+JMbRdqcPMoA6IncSRNtrMJjtk=; b=BaTb3z3XYlScmeBItSh/MvCiFqQAiw+PuT5jKY27dLjGZd01F8XOgIFoy1KI5ywHm7 VWjDfPn4cJLFaEwasSCSZcGmztfmPqU9Tm0jJsBDHlwLFJCH1pn+U+XDlD3I81ODg8fN +IXVcUMFtsQY6Gd4nJHfEhLKqty2dZW2gWWL+yZorJPsuiR5Rq4qxxsF5OEqgc8ylgUt y3tN9mgjNrCmtCTEwtDoUmRmA7VXUHs7Buhhh1GTJ74f1QmSQhiI0MYGtkKfO91s5byY pqQGA+8YYvQDWYoaYbW8Ew9TsoJmKc6/f9NUlaYPKfIBc+S8crTaGSdUOPKjYVrRh0Yp UiSg== X-Gm-Message-State: AC+VfDwTCDC0arr0I8vwazIbcNFe8SlBiRoe/pwfmJhost5FdIi1wUTl D7vaKnLT55yY3FZgjLccdYcEHQ== X-Google-Smtp-Source: ACHHUZ6IzlQYehvkbwm6qTB7qvbww6jKgEwXRnqs2X+ZAvHSdOqqO5hMcbKXrRtXSYnzqJ1v0JsE2A== X-Received: by 2002:a17:903:1105:b0:1b3:ebda:654e with SMTP id n5-20020a170903110500b001b3ebda654emr20780380plh.5.1687424227653; Thu, 22 Jun 2023 01:57:07 -0700 (PDT) Received: from C02DW0BEMD6R.bytedance.net ([139.177.225.254]) by smtp.gmail.com with ESMTPSA id h2-20020a170902f7c200b001b549fce345sm4806971plw.230.2023.06.22.01.57.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 22 Jun 2023 01:57:07 -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 Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, intel-gfx@lists.freedesktop.org, dri-devel@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 23/29] mm: shrinker: add refcount and completion_wait fields Date: Thu, 22 Jun 2023 16:53:29 +0800 Message-Id: <20230622085335.77010-24-zhengqi.arch@bytedance.com> X-Mailer: git-send-email 2.24.3 (Apple Git-128) In-Reply-To: <20230622085335.77010-1-zhengqi.arch@bytedance.com> References: <20230622085335.77010-1-zhengqi.arch@bytedance.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org This commit introduces refcount and completion_wait fields to struct shrinker to manage the life cycle of shrinker instance. Just a preparation work for implementing the lockless slab shrink, no functional changes. Signed-off-by: Qi Zheng --- include/linux/shrinker.h | 11 +++++++++++ mm/vmscan.c | 5 +++++ 2 files changed, 16 insertions(+) diff --git a/include/linux/shrinker.h b/include/linux/shrinker.h index 4094e4c44e80..7bfeb2f25246 100644 --- a/include/linux/shrinker.h +++ b/include/linux/shrinker.h @@ -4,6 +4,8 @@ #include #include +#include +#include /* * This struct is used to pass information from page reclaim to the shrinkers. @@ -70,6 +72,9 @@ struct shrinker { int seeks; /* seeks to recreate an obj */ unsigned flags; + refcount_t refcount; + struct completion completion_wait; + void *private_data; /* These are for internal use */ @@ -118,6 +123,12 @@ struct shrinker *shrinker_alloc_and_init(count_objects_cb count, void shrinker_free(struct shrinker *shrinker); void unregister_and_free_shrinker(struct shrinker *shrinker); +static inline void shrinker_put(struct shrinker *shrinker) +{ + if (refcount_dec_and_test(&shrinker->refcount)) + complete(&shrinker->completion_wait); +} + #ifdef CONFIG_SHRINKER_DEBUG extern int shrinker_debugfs_add(struct shrinker *shrinker); extern struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker, diff --git a/mm/vmscan.c b/mm/vmscan.c index 3a8d50ad6ff6..6f9c4750effa 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -740,6 +740,8 @@ void free_prealloced_shrinker(struct shrinker *shrinker) void register_shrinker_prepared(struct shrinker *shrinker) { down_write(&shrinker_rwsem); + refcount_set(&shrinker->refcount, 1); + init_completion(&shrinker->completion_wait); list_add_tail(&shrinker->list, &shrinker_list); shrinker->flags |= SHRINKER_REGISTERED; shrinker_debugfs_add(shrinker); @@ -794,6 +796,9 @@ void unregister_shrinker(struct shrinker *shrinker) if (!(shrinker->flags & SHRINKER_REGISTERED)) return; + shrinker_put(shrinker); + wait_for_completion(&shrinker->completion_wait); + down_write(&shrinker_rwsem); list_del(&shrinker->list); shrinker->flags &= ~SHRINKER_REGISTERED;