From patchwork Wed May 31 09:57:36 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qi Zheng X-Patchwork-Id: 101314 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:994d:0:b0:3d9:f83d:47d9 with SMTP id k13csp2766695vqr; Wed, 31 May 2023 03:15:36 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ5FxJ11JQEJ4ZZSRP7T6bosXJut0zyqyUSvM64VzzmzmSnwDfxHLGI8iIST4O3POywV46dq X-Received: by 2002:a05:6a00:2393:b0:64d:2a87:2596 with SMTP id f19-20020a056a00239300b0064d2a872596mr7654345pfc.10.1685528136274; Wed, 31 May 2023 03:15:36 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1685528136; cv=none; d=google.com; s=arc-20160816; b=SQ2lz1DuKmGBBMZBxURhzcbalgjz6p9Zpe4KDLpg0fKCKsOpB0wXM4kdVQmB/7CYxn UL+FczQhFHNQvG7+sb2ON4tZVFuWB7BzXKl3zYOdbK6QhNNGx3MP1KgC1EvmrJz/JEx0 javmPuaHLsBCpKAf0x0SipY0x0QdQ1BfoQ0zvl+hSPpe8oCiRhfDyWZD4Y/lxFOKg+Aj P8AT6fyjDxBWQg04vpcI6LbFO3CJ1QubAkDY4hHptJfgQdqwu1CHG+kHxgqXaEXeDoGT 5LT1DbEJ4uhFfEEQqGgrpaE1+2qg3G4E3DhnDm6MdHFzjQMzS0GVv9Bpicxzstkj3WAh jVbA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=ZzyzkXd70pYEdWJhGutN+U1hmZmD/p5d/wpcM6Ajy+8=; b=iTgK7yqK7fThhM+JgL60CqT53dbj96YUcsyD3JTFD4UV6Df01nTfjYRO+/w6pTSdKM CSAtBA65wSgearAtW6sOz+st8RdRSORA5sR26+a3YOQvPTsrh/omX3LaalCMrUyfx5+6 WdjuBIp6PKUlKktFxV61iorxoLXIlJi2dO7DL44uSzelcweKceEypEUYwPaQhsVKdZEq WZmLu6v80ouOF5e0MFr9wMSN83c+dFWHLvup+P76dH8TJyvgXILrjEeim04UwWf4SFQg EokNd1kYeqSz/25PtszJFgMjKgNt3CzXuX4rxMbPqhHvYfyhshDqHFHWX2aXccMDl5zv isXg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linux.dev header.s=key1 header.b=ZihWgnR2; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linux.dev Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id k7-20020a635607000000b0053f047e96a2si767568pgb.94.2023.05.31.03.15.24; Wed, 31 May 2023 03:15:36 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@linux.dev header.s=key1 header.b=ZihWgnR2; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linux.dev Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235694AbjEaJ65 (ORCPT + 99 others); Wed, 31 May 2023 05:58:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54398 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232459AbjEaJ6x (ORCPT ); Wed, 31 May 2023 05:58:53 -0400 Received: from out-21.mta0.migadu.com (out-21.mta0.migadu.com [IPv6:2001:41d0:1004:224b::15]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DDF9CE50 for ; Wed, 31 May 2023 02:58:28 -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=1685527104; 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=ZzyzkXd70pYEdWJhGutN+U1hmZmD/p5d/wpcM6Ajy+8=; b=ZihWgnR2scrQOnB2k5nDPiR/oFSAGcE5oxTl8DJZlC6c35SkDHP860/TT0nEoqYq/lrcq1 d6CKRaCpb2dkgODgBX/qkpML3eCN0n5h1kziLNHv4ErGYZOVxBG6L8XG40g2Y8QxSO+u0s Pr9f8hmxkoCyCfWi4RAZ5pmhxQ/yWCA= From: Qi Zheng To: akpm@linux-foundation.org, tkhai@ya.ru, roman.gushchin@linux.dev, vbabka@suse.cz, viro@zeniv.linux.org.uk, brauner@kernel.org, djwong@kernel.org, hughd@google.com, paulmck@kernel.org, muchun.song@linux.dev Cc: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-kernel@vger.kernel.org, Qi Zheng Subject: [PATCH 2/8] mm: vmscan: split unregister_shrinker() Date: Wed, 31 May 2023 09:57:36 +0000 Message-Id: <20230531095742.2480623-3-qi.zheng@linux.dev> In-Reply-To: <20230531095742.2480623-1-qi.zheng@linux.dev> References: <20230531095742.2480623-1-qi.zheng@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_NONE,SPF_PASS, T_SCC_BODY_TEXT_LINE,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1767404351124374495?= X-GMAIL-MSGID: =?utf-8?q?1767404351124374495?= From: Kirill Tkhai This and the next patches in this series aim to make time effect of synchronize_srcu() invisible for user. The patch splits unregister_shrinker() in two functions: unregister_shrinker_delayed_initiate() unregister_shrinker_delayed_finalize() and shrinker users may make the second of them to be called asynchronous (e.g., from workqueue). Next patches make superblock shrinker to follow this way, so user-visible umount() time won't contain delays from synchronize_srcu(). Signed-off-by: Kirill Tkhai Signed-off-by: Qi Zheng --- include/linux/shrinker.h | 2 ++ mm/vmscan.c | 22 ++++++++++++++++++---- 2 files changed, 20 insertions(+), 4 deletions(-) diff --git a/include/linux/shrinker.h b/include/linux/shrinker.h index 224293b2dd06..e9d5a19d83fe 100644 --- a/include/linux/shrinker.h +++ b/include/linux/shrinker.h @@ -102,6 +102,8 @@ extern void register_shrinker_prepared(struct shrinker *shrinker); extern int __printf(2, 3) register_shrinker(struct shrinker *shrinker, const char *fmt, ...); extern void unregister_shrinker(struct shrinker *shrinker); +extern void unregister_shrinker_delayed_initiate(struct shrinker *shrinker); +extern void unregister_shrinker_delayed_finalize(struct shrinker *shrinker); extern void free_prealloced_shrinker(struct shrinker *shrinker); extern void synchronize_shrinkers(void); diff --git a/mm/vmscan.c b/mm/vmscan.c index a773e97e152e..baf8d2327d70 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -799,10 +799,7 @@ int register_shrinker(struct shrinker *shrinker, const char *fmt, ...) #endif EXPORT_SYMBOL(register_shrinker); -/* - * Remove one - */ -void unregister_shrinker(struct shrinker *shrinker) +void unregister_shrinker_delayed_initiate(struct shrinker *shrinker) { struct dentry *debugfs_entry; int debugfs_id; @@ -819,6 +816,13 @@ void unregister_shrinker(struct shrinker *shrinker) mutex_unlock(&shrinker_mutex); shrinker_debugfs_remove(debugfs_entry, debugfs_id); +} +EXPORT_SYMBOL(unregister_shrinker_delayed_initiate); + +void unregister_shrinker_delayed_finalize(struct shrinker *shrinker) +{ + if (!shrinker->nr_deferred) + return; atomic_inc(&shrinker_srcu_generation); synchronize_srcu(&shrinker_srcu); @@ -826,6 +830,16 @@ void unregister_shrinker(struct shrinker *shrinker) kfree(shrinker->nr_deferred); shrinker->nr_deferred = NULL; } +EXPORT_SYMBOL(unregister_shrinker_delayed_finalize); + +/* + * Remove one + */ +void unregister_shrinker(struct shrinker *shrinker) +{ + unregister_shrinker_delayed_initiate(shrinker); + unregister_shrinker_delayed_finalize(shrinker); +} EXPORT_SYMBOL(unregister_shrinker); /**