From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Turner Subject: Re: [PATCH v4 4/9] index-helper: new daemon for caching index and related stuff Date: Mon, 02 Nov 2015 17:14:11 -0500 Organization: Twitter Message-ID: <1446502451.4131.26.camel@twopensource.com> References: <1446385369-8669-1-git-send-email-pclouds@gmail.com> <1446385369-8669-5-git-send-email-pclouds@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: git@vger.kernel.org, Christian Couder To: =?UTF-8?Q?Nguy=E1=BB=85n_Th=C3=A1i_Ng=E1=BB=8Dc?= Duy X-From: git-owner@vger.kernel.org Mon Nov 02 23:14:36 2015 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1ZtNMv-0001vR-J4 for gcvg-git-2@plane.gmane.org; Mon, 02 Nov 2015 23:14:25 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752729AbbKBWOU convert rfc822-to-quoted-printable (ORCPT ); Mon, 2 Nov 2015 17:14:20 -0500 Received: from mail-qg0-f45.google.com ([209.85.192.45]:35884 "EHLO mail-qg0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751182AbbKBWON (ORCPT ); Mon, 2 Nov 2015 17:14:13 -0500 Received: by qgad10 with SMTP id d10so128343948qga.3 for ; Mon, 02 Nov 2015 14:14:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=twopensource_com.20150623.gappssmtp.com; s=20150623; h=message-id:subject:from:to:cc:date:in-reply-to:references :organization:content-type:mime-version:content-transfer-encoding; bh=X3QGwa+xT8ms/5nkuj5FiqwdHH0SkAZWRwumrbKSlt0=; b=K6Gl/LTD9lvro+KkzEnw50A43VVxMnnXcmtpG883oEdQXo2vWN6n+9FloRs3FNnM8I zHRxNV2NzpqSfIyzH9FwKMlUZEiMIrmH5gZeBmG0oyawvsPkztzDpvI81lxffK4kSvLS qcRN46j9UUmwJvUb/6YOGB+wDV+r6UyY1PpXVBYxnQUO5cvAnyM2o7GvOJoODjxB9Qsc ZBJBsBFKKfuAjQDm1nChl6MZ+80M5ESwBJE64Mjucdvize2EGy8mFkEZQtr8VCPuP//w UrhHnBLGwOQb4Tf3as0hNM2j1OGF1rI0Q1lZ2//PfxTajmqiH1h3UUBNBI+fmXJpG2vp UWsA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:message-id:subject:from:to:cc:date:in-reply-to :references:organization:content-type:mime-version :content-transfer-encoding; bh=X3QGwa+xT8ms/5nkuj5FiqwdHH0SkAZWRwumrbKSlt0=; b=hEhykDGoMI9bCgQpX6L2m4H1omgA88o7OjdbClcwWoype+zb23Lqn8vHQNHOkeowUy 3Fh0Gy/E7f5eY9B6iKXE019o8sxmu4+DwUcMGVqoz1YdMCFPWLd9GqS14yMA5E1eCBpd yAxJ8D+nTUAd0jtS6IaaZismtsDIyKKkdgcYS3ZNJyb9jqDZ5VDx3Y1yaapetjTvTPvl FtmQW2NhV5QLA435w7XsOwo8LiRfOzr/9zoNFsu4WcpSS0UZ4sGX5S9f1N+7CgmF70S4 vGVXGsSHv2cde/ELDOcZYLmpa/WKiGaF/CF/9mNJorjph3Z0B83L4h6os+Nb51PK9VYA 9s5w== X-Gm-Message-State: ALoCoQmd1GA6swRWo6ke4FIP5bYIugtCttkNxJEBkHug9MF53SAvxWVFA3f/7+XEL8BEKG8w65ju X-Received: by 10.140.165.205 with SMTP id l196mr33122802qhl.101.1446502453038; Mon, 02 Nov 2015 14:14:13 -0800 (PST) Received: from ubuntu ([192.133.79.145]) by smtp.gmail.com with ESMTPSA id m64sm5395117qhm.1.2015.11.02.14.14.11 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 02 Nov 2015 14:14:12 -0800 (PST) In-Reply-To: <1446385369-8669-5-git-send-email-pclouds@gmail.com> X-Mailer: Evolution 3.12.11-0ubuntu3 Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: On Sun, 2015-11-01 at 14:42 +0100, Nguy=E1=BB=85n Th=C3=A1i Ng=E1=BB=8D= c Duy wrote: > + memcpy(new_mmap, istate->mmap, istate->mmap_size - 20); > + > + /* > + * The trailing hash must be written last after everything is > + * written. It's the indication that the shared memory is now > + * ready. > + */ > + hashcpy((unsigned char *)new_mmap + istate->mmap_size - 20, is->sha= 1); > +} You need a memory barrier here. Otherwise, compilers may reorder these statements. > +#define SHM_PATH_LEN 72 /* we don't create very long paths.. */ > + > +ssize_t git_shm_map(int oflag, int perm, ssize_t length, void **mmap= , > + int prot, int flags, const char *fmt, ...) > +{ > + va_list ap; > + char path[SHM_PATH_LEN]; > + int fd; > + > + path[0] =3D '/'; > + va_start(ap, fmt); > + vsprintf(path + 1, fmt, ap); > + va_end(ap); This would be safer with vsnprintf.