From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-2.7 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_HI,RCVD_IN_SORBS_SPAM, RP_MATCHES_RCVD shortcircuit=no autolearn=no autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 5677A20188 for ; Sat, 13 May 2017 23:46:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756164AbdEMXqF (ORCPT ); Sat, 13 May 2017 19:46:05 -0400 Received: from mail-qt0-f195.google.com ([209.85.216.195]:35229 "EHLO mail-qt0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755689AbdEMXqB (ORCPT ); Sat, 13 May 2017 19:46:01 -0400 Received: by mail-qt0-f195.google.com with SMTP id r58so11266851qtb.2 for ; Sat, 13 May 2017 16:46:01 -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:in-reply-to:references :mime-version:content-transfer-encoding; bh=UWClpfI4rKACf9bPthBhb/ElgzdCADEsAPds6SfkLqQ=; b=LRin61tC8Xh8brW6dHzvMu9/9BS6JbAe7uRaqhaaqBDQRhRMUtFQsd2EDCQOqPBeTQ ATyxqxbXj/eDG8rSbma+KIBFNT4ah35KF4dJpUrZyss2m76xP3WLQArhfohC3U+STgmS aiEIhjzNN7WeQJ2R6wyPy+NHtbVwJp0o3szmR9aa8lrWDo4WhAsplRaR+vuxjDKxgV1h dokhaoAVLfMH4mQBZ+MbXQAC8zMXDYdt1n+82AODzFSPnQ3AeZ9lfHtjAmNHKvRvKx4/ 2bMyTK1doQy1pX3rHgjjF7OgLVuFOmmOZ/AqG3d5ctRfj1w9B5MWx2Lq980P92qpSbEY nqXg== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=UWClpfI4rKACf9bPthBhb/ElgzdCADEsAPds6SfkLqQ=; b=sJTKKCMzrsdhwxxCFX9csmsUAoBkcXxGItd1NkV0jlPtcVR5EEBILKgSajmRKMzQsI 1LQpfdsrHFSaNEp3Q+bPiXEHGrzPP1Tzgj53c8zh1TkDpFRE3Soh3Y83yOEz3OkSnCh1 e4My/VbofWN9y+Y5TN5+f8Wz7ZaGOOXTgrx3PRE6xMqbiOkVYOBnFgibidMkcP7T4mII bx5/+9iPic9mkrXWNtc7x3IXVXsuX7yzqt0aeM8IWxz9ACVD/hItJ4I9Z4hqwrGRmRIM IGOrqHZA9rfcE8Kj0JVNPrsj9KjBxSCpV5+2ambtXdJywqtftLW2kcCIOSZn6RrJw7ii 5ifA== X-Gm-Message-State: AODbwcBJwni4JfAWIYNeORm4ktU63bPQZOEjy+iXts6NU09bkjtADQ+l lMbMaaI4bubWuQ== X-Received: by 10.237.48.66 with SMTP id 60mr11197957qte.25.1494719160695; Sat, 13 May 2017 16:46:00 -0700 (PDT) Received: from u.nix.is ([2a01:4f8:190:5095::2]) by smtp.gmail.com with ESMTPSA id h14sm5319234qta.18.2017.05.13.16.45.58 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 13 May 2017 16:45:59 -0700 (PDT) From: =?UTF-8?q?=C3=86var=20Arnfj=C3=B6r=C3=B0=20Bjarmason?= To: git@vger.kernel.org Cc: Junio C Hamano , Jeff King , Jeffrey Walton , =?UTF-8?q?Micha=C5=82=20Kiedrowicz?= , J Smith , Victor Leschuk , =?UTF-8?q?Nguy=E1=BB=85n=20Th=C3=A1i=20Ng=E1=BB=8Dc=20Duy?= , Fredrik Kuivinen , Brandon Williams , =?UTF-8?q?=C3=86var=20Arnfj=C3=B6r=C3=B0=20Bjarmason?= Subject: [PATCH v2 2/7] grep: skip pthreads overhead when using one thread Date: Sat, 13 May 2017 23:45:30 +0000 Message-Id: <20170513234535.12749-3-avarab@gmail.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170513234535.12749-1-avarab@gmail.com> References: <20170513234535.12749-1-avarab@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Skip the administrative overhead of using pthreads when only using one thread. Instead take the non-threaded path which would be taken under NO_PTHREADS. The threading support was initially added in commit 5b594f457a ("Threaded grep", 2010-01-25) with a hardcoded compile-time number of 8 threads. Later the number of threads was made configurable in commit 89f09dd34e ("grep: add --threads= option and grep.threads configuration", 2015-12-15). That change did not add any special handling for --threads=1. Now we take a slightly faster path by skipping thread handling entirely when 1 thread is requested. Signed-off-by: Ævar Arnfjörð Bjarmason --- builtin/grep.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/builtin/grep.c b/builtin/grep.c index 12e62fcbf3..bd008cb100 100644 --- a/builtin/grep.c +++ b/builtin/grep.c @@ -1238,6 +1238,8 @@ int cmd_grep(int argc, const char **argv, const char *prefix) num_threads = GREP_NUM_THREADS_DEFAULT; else if (num_threads < 0) die(_("invalid number of threads specified (%d)"), num_threads); + if (num_threads == 1) + num_threads = 0; #else if (num_threads) warning(_("no threads support, ignoring --threads")); -- 2.11.0