From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-4.0 required=3.0 tests=AWL,BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 5F88020248 for ; Thu, 14 Mar 2019 00:31:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726946AbfCNAbe (ORCPT ); Wed, 13 Mar 2019 20:31:34 -0400 Received: from cloud.peff.net ([104.130.231.41]:50092 "HELO cloud.peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1726799AbfCNAbe (ORCPT ); Wed, 13 Mar 2019 20:31:34 -0400 Received: (qmail 31356 invoked by uid 109); 14 Mar 2019 00:31:35 -0000 Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.94) with SMTP; Thu, 14 Mar 2019 00:31:35 +0000 Authentication-Results: cloud.peff.net; auth=none Received: (qmail 17864 invoked by uid 111); 14 Mar 2019 00:30:38 -0000 Received: from sigill.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.7) by peff.net (qpsmtpd/0.94) with (ECDHE-RSA-AES256-GCM-SHA384 encrypted) SMTP; Wed, 13 Mar 2019 20:30:38 -0400 Authentication-Results: peff.net; auth=none Received: by sigill.intra.peff.net (sSMTP sendmail emulation); Wed, 13 Mar 2019 20:30:16 -0400 Date: Wed, 13 Mar 2019 20:30:16 -0400 From: Jeff King To: =?utf-8?B?w4Z2YXIgQXJuZmrDtnLDsA==?= Bjarmason Cc: git@vger.kernel.org, Junio C Hamano , =?utf-8?B?Tmd1eeG7hW4gVGjDoWkgTmfhu41j?= Duy , Michael Haggerty , Stefan Beller , Jonathan Nieder Subject: Re: [PATCH 3/5] gc: refactor a "call me once" pattern Message-ID: <20190314003016.GH31968@sigill.intra.peff.net> References: <87imwmbv7l.fsf@evledraar.gmail.com> <20190313235439.30439-4-avarab@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20190313235439.30439-4-avarab@gmail.com> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Thu, Mar 14, 2019 at 12:54:37AM +0100, Ævar Arnfjörð Bjarmason wrote: > Change an idiom we're using to ensure that gc_before_repack() only > does work once (see 62aad1849f ("gc --auto: do not lock refs in the > background", 2014-05-25)) to be more obvious. > > Nothing except this function cares about the "pack_refs" and > "prune_reflogs" variables, so let's not leave the reader wondering if > they're being zero'd out for later use somewhere else. I agree the existing code is not very obvious about what it's trying to do. I think a comment would have helped a lot. Your rewrite is definitely better than the original, but I think it might also benefit from a comment. I.e., something like: > static void gc_before_repack(void) > { /* * We may be called twice, as both the pre- and post-daemonized * phases will call us, but running these commands more than * once is pointless and wasteful. */ > + static int done = 0; > + if (done++) > + return; -Peff