From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff King Subject: [PATCH 16/17] commit: convert commit->buffer to a slab Date: Tue, 10 Jun 2014 17:43:02 -0400 Message-ID: <20140610214302.GP19147@sigill.intra.peff.net> References: <20140610213509.GA26979@sigill.intra.peff.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Cc: Junio C Hamano , Christian Couder , Jakub Narebski , Eric Sunshine To: git@vger.kernel.org X-From: git-owner@vger.kernel.org Tue Jun 10 23:43:10 2014 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 1WuToz-0007DX-Aq for gcvg-git-2@plane.gmane.org; Tue, 10 Jun 2014 23:43:09 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753548AbaFJVnF (ORCPT ); Tue, 10 Jun 2014 17:43:05 -0400 Received: from cloud.peff.net ([50.56.180.127]:41442 "HELO peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1753354AbaFJVnE (ORCPT ); Tue, 10 Jun 2014 17:43:04 -0400 Received: (qmail 19986 invoked by uid 102); 10 Jun 2014 21:43:03 -0000 Received: from c-71-63-4-13.hsd1.va.comcast.net (HELO sigill.intra.peff.net) (71.63.4.13) (smtp-auth username relayok, mechanism cram-md5) by peff.net (qpsmtpd/0.84) with ESMTPA; Tue, 10 Jun 2014 16:43:03 -0500 Received: by sigill.intra.peff.net (sSMTP sendmail emulation); Tue, 10 Jun 2014 17:43:02 -0400 Content-Disposition: inline In-Reply-To: <20140610213509.GA26979@sigill.intra.peff.net> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: This will make it easier to manage the buffer cache independently of the "struct commit" objects. It also shrinks "struct commit" by one pointer, which may be helpful. Unfortunately it does not reduce the max memory size of something like "rev-list", because rev-list uses get_cached_commit_buffer() to decide not to show each commit's output (and due to the design of slab_at, accessing the slab requires us to extend it, allocating exactly the same number of buffer pointers we dropped from the commit structs). Signed-off-by: Jeff King --- commit.c | 20 +++++++++++++------- commit.h | 1 - 2 files changed, 13 insertions(+), 8 deletions(-) diff --git a/commit.c b/commit.c index 1903dde..e289c78 100644 --- a/commit.c +++ b/commit.c @@ -245,14 +245,17 @@ int unregister_shallow(const unsigned char *sha1) return 0; } +define_commit_slab(buffer_slab, void *); +static struct buffer_slab buffer_slab = COMMIT_SLAB_INIT(1, buffer_slab); + void set_commit_buffer(struct commit *commit, void *buffer) { - commit->buffer = buffer; + *buffer_slab_at(&buffer_slab, commit) = buffer; } const void *get_cached_commit_buffer(const struct commit *commit) { - return commit->buffer; + return *buffer_slab_at(&buffer_slab, commit); } const void *get_commit_buffer(const struct commit *commit) @@ -274,20 +277,23 @@ const void *get_commit_buffer(const struct commit *commit) void unuse_commit_buffer(const struct commit *commit, const void *buffer) { - if (commit->buffer != buffer) + void *cached = *buffer_slab_at(&buffer_slab, commit); + if (cached != buffer) free((void *)buffer); } void free_commit_buffer(struct commit *commit) { - free(commit->buffer); - commit->buffer = NULL; + void **b = buffer_slab_at(&buffer_slab, commit); + free(*b); + *b = NULL; } const void *detach_commit_buffer(struct commit *commit) { - void *ret = commit->buffer; - commit->buffer = NULL; + void **b = buffer_slab_at(&buffer_slab, commit); + void *ret = *b; + *b = NULL; return ret; } diff --git a/commit.h b/commit.h index 5ce5ce7..e1c2569 100644 --- a/commit.h +++ b/commit.h @@ -20,7 +20,6 @@ struct commit { unsigned long date; struct commit_list *parents; struct tree *tree; - char *buffer; }; extern int save_commit_buffer; -- 2.0.0.729.g520999f