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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 5AAA0C47E48 for ; Thu, 15 Jul 2021 10:36:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3F9E7613C1 for ; Thu, 15 Jul 2021 10:36:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232570AbhGOKjE (ORCPT ); Thu, 15 Jul 2021 06:39:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55882 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232526AbhGOKjE (ORCPT ); Thu, 15 Jul 2021 06:39:04 -0400 Received: from mail-ed1-x52b.google.com (mail-ed1-x52b.google.com [IPv6:2a00:1450:4864:20::52b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5A15EC06175F; Thu, 15 Jul 2021 03:36:10 -0700 (PDT) Received: by mail-ed1-x52b.google.com with SMTP id h8so7427638eds.4; Thu, 15 Jul 2021 03:36:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=FwwLaXHeFD676V7GhX0BNFyfYdUME4hhQYfPK3kPSew=; b=bHS8DCtxxF9lDg973HKJJvhPTD5l+/YGDoUowamOiEvU21nCtztYzu14qnsiLLB2DX AJX+1lqcspDexte1ViAeJBoGWcK/0aff1fde/yXpJ8EznldR+x8ghUulD6onO8UETrr4 fgHeX3e+w2JncxgI5BqaX4v6UcgWekFKCkL8VGz/gAlTuPdEbaVLSrCa+8ekMHG9IRdu tOp3MbJ3F/ktNhhgj5iiMDY9PEegW8HzwpUCwKuQHJoKXvXZDUSllTmO0MYGwm2oVnJ2 EObTb46gKN3/K+5nC9TxGQAk2o4UFdiw3HDYe4yYBCgaGal37h2hTA33zsKT04uD+oS+ 91Iw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=FwwLaXHeFD676V7GhX0BNFyfYdUME4hhQYfPK3kPSew=; b=gCaZnk+JNND+Hl9M1qmXZ6rFg3MC3yCBmz/X32NbFyV92BPLx2zVA0o7kyWJJDSdDG ldzBG7iZSM+Vu7ENXY6g/a9Nb3UtBYrFx3t29Pt/Tkd6DgWUfBW+5YsPJOCcoxIvW+wI D8djUtYaf/dGA955VX4ppPv48C983q+jBDlrcMN2ZAvUHvOUji7SjH/mhnrRSwgcTlMh FloHn49gpror7RSFNbjewuGr7AVAe9Pi4G9YntR8QGCt9HEOeIGq9Qw2p1RrTUqRCHuB Xsk5Iq8EGMYAGdfRuodo6ztbDNaqrOjwaQl+VpgntSqAZJtTHqcNieR5WKRsvi8gNFD8 F4IA== X-Gm-Message-State: AOAM532FvZsKbVLbAMfxpgKz0FGCxDM0A6RXNk4H9KkLtvagkwWoQFE2 U7F7UOe6uB59SfjuSNIOLuk= X-Google-Smtp-Source: ABdhPJxvkCRrLxCUkrvohOuOcpaB29uUCe4cVF9v03r+3+Rx/zI4fmG8nCcGNfEl2WNy/Ch/CH9/Rw== X-Received: by 2002:aa7:c04e:: with SMTP id k14mr5866183edo.157.1626345369016; Thu, 15 Jul 2021 03:36:09 -0700 (PDT) Received: from carbon.v ([108.61.166.58]) by smtp.googlemail.com with ESMTPSA id dd24sm2228464edb.45.2021.07.15.03.36.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 15 Jul 2021 03:36:08 -0700 (PDT) From: Dmitry Kadashev To: Jens Axboe , Alexander Viro , Christian Brauner , Linus Torvalds Cc: linux-fsdevel@vger.kernel.org, io-uring@vger.kernel.org, Dmitry Kadashev Subject: [PATCH 00/14] namei: clean up retry logic in various do_* functions Date: Thu, 15 Jul 2021 17:35:46 +0700 Message-Id: <20210715103600.3570667-1-dkadashev@gmail.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Suggested by Linus in https://lore.kernel.org/io-uring/CAHk-=wh=cpt_tQCirzFZRPawRpbuFTZ2MxNpXiyUF+eBXF=+sw@mail.gmail.com/ This patchset does all the do_* functions one by one. The idea is to move the main logic to a helper function and handle stale retries / struct filename cleanups outside, which makes the logic easier to follow. There are a few minor changes in behavior: 1. filename_lookup() / filename_parentat() / filename_create() do their own retries on ESTALE (regardless of flags), and previously they were exempt from retries in the do_* functions (but they *were* called on retry - it's just the return code wasn't checked for ESTALE). And now the retry is done on the upper level, and so technically it could be called a behavior change. Hopefully it's an edge case where an additional check does not matter. 2. Some safety checks like may_mknod() / flags validation are now repeated on retry. Those are mostly trivial and retry is a slow path, so that should be OK. 3. retry_estale() is wrapped into unlikely() now On top of https://lore.kernel.org/io-uring/20210708063447.3556403-1-dkadashev@gmail.com/ v2: - Split flow changes and code reorganization to different commits; - Move more checks into the new helpers, to avoid gotos in the touched do_* functions completely; - Add unlikely() around retry_estale(); - Name the new helper functions try_* instead of *_helper; Dmitry Kadashev (14): namei: prepare do_rmdir for refactoring namei: clean up do_rmdir retry logic namei: prepare do_unlinkat for refactoring namei: clean up do_unlinkat retry logic namei: prepare do_mkdirat for refactoring namei: clean up do_mkdirat retry logic namei: prepare do_mknodat for refactoring namei: clean up do_mknodat retry logic namei: prepare do_symlinkat for refactoring namei: clean up do_symlinkat retry logic namei: prepare do_linkat for refactoring namei: clean up do_linkat retry logic namei: prepare do_renameat2 for refactoring namei: clean up do_renameat2 retry logic fs/namei.c | 252 +++++++++++++++++++++++++++++------------------------ 1 file changed, 140 insertions(+), 112 deletions(-) -- 2.30.2