From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 511D6C43144 for ; Wed, 27 Jun 2018 19:53:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EE57924588 for ; Wed, 27 Jun 2018 19:53:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="YFW6PBRK" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EE57924588 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966465AbeF0Txq (ORCPT ); Wed, 27 Jun 2018 15:53:46 -0400 Received: from mail-wr0-f195.google.com ([209.85.128.195]:35387 "EHLO mail-wr0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966412AbeF0Txm (ORCPT ); Wed, 27 Jun 2018 15:53:42 -0400 Received: by mail-wr0-f195.google.com with SMTP id c13-v6so3188759wrq.2 for ; Wed, 27 Jun 2018 12:53:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:mime-version:content-disposition :user-agent; bh=/o13KHR6wd0+0rl72f1gK/Qs+scE945pItDzEozSwuY=; b=YFW6PBRKbKv3wf87HnmgYfeg3v0CKaWn6WAKJdwqgTrTrn3nLhGoM2S5J+FT1IWTZv Zd78I9gqgKpoObAyTXChXot+ezG6E0aAhu9YtLBikgSDR9rOkLpOUoDdgFdf/W9RJFKL 6W9RL3rkSQk2vmlE6jZFCGBE2DnxwTncMFXmTSQ+trR3JeKcwapBJi1YuZ/jBrCmmQbf ZeDnSCXs+7YXl08M3/t68Q1gd2vg8hGjOQX41hZxOkUSnQ7jFLwXlK87+vSg9MvUe4Mo GGDRCsoOrtSQkVH3lONKBT8RuYa1si8gLny2ZhVNvD5coLMv3stjRpaw3YIiX6MkAtSG AZIw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:mime-version :content-disposition:user-agent; bh=/o13KHR6wd0+0rl72f1gK/Qs+scE945pItDzEozSwuY=; b=oT6d2QemUHRniZnqECIfzxdkoNPdZCqrS7iDvG0lzv68h32CdFUw3An61BXdNDhh1H uiNEtVMTYP7g6AupIlj8+XkSIBv7VTWi1BZyw0l/wFM4lFz1jgfkR+WDzrfA9JNWtVk6 VtE8F6KAy/eJ/3nRGOuSp2/aRJDmY7mjj7JjGXpPiCZ7BBHvNiqt+qmuyFtWxuli73vy PI5DAXwUjx4Xax2mZewPBTKqMjfSDxLnxU5FmhPZ5EApnNzTR4cFacTmD7OLFREl7VT7 02ZF8TrZIg2Cy9N9lSk/z8hmZuZHsBv+cioeuh27n+sg+IpkSezTcMYMlpeF6i4REZWM 67aQ== X-Gm-Message-State: APt69E05PCfTRZGPgXcIGaRfibRyrGAhhIEZbxyMXWEnRVn7hi7Sgvg+ YY5471s9PyWZKT2QwGO2Ug== X-Google-Smtp-Source: AAOMgpetE1RlfTiFPmT52QqOCuNP5TaQoDdnqMXjqKC/LujNkYtdWEFWySGvOEnLtq5vQUXfILU3xw== X-Received: by 2002:adf:f98a:: with SMTP id f10-v6mr6257279wrr.105.1530129221572; Wed, 27 Jun 2018 12:53:41 -0700 (PDT) Received: from avx2 (nat4-minsk-pool-46-53-177-92.telecom.by. [46.53.177.92]) by smtp.gmail.com with ESMTPSA id n18-v6sm11524098wrj.58.2018.06.27.12.53.40 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 27 Jun 2018 12:53:40 -0700 (PDT) Date: Wed, 27 Jun 2018 22:53:39 +0300 From: Alexey Dobriyan To: akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org Subject: [PATCH] proc: smaller readlock section in readdir("/proc") Message-ID: <20180627195339.GD18113@avx2> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Readdir context is thread local, so ->pos is thread local, move it out of readlock. Signed-off-by: Alexey Dobriyan --- fs/proc/generic.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/fs/proc/generic.c +++ b/fs/proc/generic.c @@ -286,9 +286,9 @@ int proc_readdir_de(struct file *file, struct dir_context *ctx, if (!dir_emit_dots(file, ctx)) return 0; + i = ctx->pos - 2; read_lock(&proc_subdir_lock); de = pde_subdir_first(de); - i = ctx->pos - 2; for (;;) { if (!de) { read_unlock(&proc_subdir_lock); @@ -309,8 +309,8 @@ int proc_readdir_de(struct file *file, struct dir_context *ctx, pde_put(de); return 0; } - read_lock(&proc_subdir_lock); ctx->pos++; + read_lock(&proc_subdir_lock); next = pde_subdir_next(de); pde_put(de); de = next;