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: 13261853 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id E828DC77B73 for ; Wed, 31 May 2023 09:58:27 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 698E18E0003; Wed, 31 May 2023 05:58:27 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 64A8D8E0002; Wed, 31 May 2023 05:58:27 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 510D08E0003; Wed, 31 May 2023 05:58:27 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 435C78E0002 for ; Wed, 31 May 2023 05:58:27 -0400 (EDT) Received: from smtpin14.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 0D9E9C0311 for ; Wed, 31 May 2023 09:58:27 +0000 (UTC) X-FDA: 80850100254.14.568EC90 Received: from out-7.mta0.migadu.com (out-7.mta0.migadu.com [91.218.175.7]) by imf07.hostedemail.com (Postfix) with ESMTP id 4F8344000A for ; Wed, 31 May 2023 09:58:25 +0000 (UTC) Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=ZihWgnR2; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf07.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.7 as permitted sender) smtp.mailfrom=qi.zheng@linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1685527105; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=ZzyzkXd70pYEdWJhGutN+U1hmZmD/p5d/wpcM6Ajy+8=; b=3uyajgJByU4E3Ny+d/dWvOOoEQ3HyusH0gBkcUADUU98HTAN8v71cpdR/1mORc5fUFbDZT 2Qvd0znbD8zBalPbj/+Pu+EZgBuO3y0D9BYKVUSutFDRK2m0jQurT+xBoSVMXBF2N9XUOT 1qKCB0Wikhfbi6GrUBNQX5J89iE5Cu0= ARC-Authentication-Results: i=1; imf07.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=ZihWgnR2; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf07.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.7 as permitted sender) smtp.mailfrom=qi.zheng@linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1685527105; a=rsa-sha256; cv=none; b=5m0V/lsCJ1Bi2UHH5owO7tEx3M8gR4RtSKdIvNSaL+xlk9Sa4s5Hxh8ol2lADMAAuGaWCa XGGF0mesP0WVIHEuJ9/KjQg0XWeUzp54FZJ3gBxyvJhZa3C+e1gWIvKbfDnuBCARbJwkyS pj1PQjKT+WHIIsRCnHEPZsHnxu69rV0= 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-Rspamd-Queue-Id: 4F8344000A X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: nsu3k9ri9osqucawfayb77crcprw7zxb X-HE-Tag: 1685527105-584895 X-HE-Meta: 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 c74/rNIp FnFkMx6Bh3SLjMcQYicROUgq3z/Q8CbSn8uqQI6/GGWbQ5aHpnQZRhRq0EeSJ3IooPFx/PcVU4TJzYfUdCws/j5PWxsgO8nvLv0Ms7OYyqtj7JRLCKS+LgcThUHCgtJHmy21K0ERmsGewskyKP0weiATKz7FHV57lIbaNLd5xSztXp/95zXxnZk25QpeId/6OFiNJlR2V+pvhZWbVa65NpKW88Cc6ZWTfYzWnQrNING3AZwX5y9vGlRWauw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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); /**