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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A697EC88CBF for ; Mon, 12 Jun 2023 17:30:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233871AbjFLRaa (ORCPT ); Mon, 12 Jun 2023 13:30:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40156 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237698AbjFLR3r (ORCPT ); Mon, 12 Jun 2023 13:29:47 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EF519DB; Mon, 12 Jun 2023 10:29:45 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8B888620E7; Mon, 12 Jun 2023 17:29:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BF4F2C433D2; Mon, 12 Jun 2023 17:29:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1686590985; bh=tVyezW3o2HAblHhWfBLLzXDJWYWq8x5ow1lKCcaOQkI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=hgXZWmlOMWS0quDcXThICtAZ+0rkyiTG7asel0q5gUhCktm7Oliwo79T3YUOcWqE8 Q9qPEF4STvIBjwjg9Oa5MJ2tjoIE63DZ3zbk4BTF35APAkJuAYyV71e98NAFYCuG1z ZivboAUfiXLvkTA4hJkyEU7WCGwaFNwtYF669u8uNjxHiqUIk5H19neSf9uc0+HgsK 7LyDMsI+oGuPYVJn3PC0NE3fd892RGzwo96Fcl9wZDfJutPFXH3O3uxffmo+dHUxDa rsFElNU+xRUCKgN+jWlWOAOlH04q3NAil12NAR1cjROimwyHUtMeh/NStJvKjZM8i8 VWhWyhVfikWzA== Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id 2DC1A40692; Mon, 12 Jun 2023 14:29:42 -0300 (-03) Date: Mon, 12 Jun 2023 14:29:42 -0300 From: Arnaldo Carvalho de Melo To: Ian Rogers Cc: James Clark , linux-perf-users@vger.kernel.org, Peter Zijlstra , Ingo Molnar , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Adrian Hunter , linux-kernel@vger.kernel.org Subject: Re: [PATCH] perf map: Fix refcount errors on Arm with -DREFCNT_CHECKING=1 Message-ID: References: <20230612150424.198914-1-james.clark@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Url: http://acmel.wordpress.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Mon, Jun 12, 2023 at 09:32:30AM -0700, Ian Rogers escreveu: > On Mon, Jun 12, 2023 at 8:05 AM James Clark wrote: > > > > When quitting after running a perf report, the refcount checker finds > > some double frees. The issue is that map__put() is called on a function > > argument so it removes the refcount wrapper that someone else was using. > > > > Fix it by only calling map__put() on a reference that is owned by this > > function. > > > > Signed-off-by: James Clark > > Acked-by: Ian Rogers > > > --- > > tools/perf/util/symbol-elf.c | 9 +++++---- > > tools/perf/util/symbol.c | 9 +++++---- > > 2 files changed, 10 insertions(+), 8 deletions(-) > > > > diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c > > index 63882a4db5c7..ec0d7810bbb0 100644 > > --- a/tools/perf/util/symbol-elf.c > > +++ b/tools/perf/util/symbol-elf.c > > @@ -1365,6 +1365,7 @@ static int dso__process_kernel_symbol(struct dso *dso, struct map *map, > > struct dso *curr_dso = *curr_dsop; > > struct map *curr_map; > > char dso_name[PATH_MAX]; > > + struct map *map_ref; > > nit: can we narrow the scope of this by moving it to the scope where it is used. Which is what you did in a patch I already processed, its only in tmp.perf-tools-next as I was going thru the other patches, but this one is there already. I'm checking the tools/perf/util/symbol.c part. - Arnaldo > > > > /* Adjust symbol to map to file offset */ > > if (adjust_kernel_syms) > > @@ -1390,10 +1391,10 @@ static int dso__process_kernel_symbol(struct dso *dso, struct map *map, > > if (kmaps) { > > int err; > > > > - map__get(map); > > - maps__remove(kmaps, map); > > - err = maps__insert(kmaps, map); > > - map__put(map); > > + map_ref = map__get(map); > > + maps__remove(kmaps, map_ref); > > + err = maps__insert(kmaps, map_ref); > > + map__put(map_ref); > > if (err) > > return err; > > } > > diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c > > index 6b9c55784b56..b3034fd5c0af 100644 > > --- a/tools/perf/util/symbol.c > > +++ b/tools/perf/util/symbol.c > > @@ -1368,6 +1368,7 @@ static int dso__load_kcore(struct dso *dso, struct map *map, > > int err, fd; > > char kcore_filename[PATH_MAX]; > > u64 stext; > > + struct map *map_ref; > > nit: can we narrow the scope of this by moving it to the scope where it is used. > > Thanks, > Ian > > > > > if (!kmaps) > > return -EINVAL; > > @@ -1464,10 +1465,10 @@ static int dso__load_kcore(struct dso *dso, struct map *map, > > map__set_map_ip(map, map__map_ip_ptr(new_map)); > > map__set_unmap_ip(map, map__unmap_ip_ptr(new_map)); > > /* Ensure maps are correctly ordered */ > > - map__get(map); > > - maps__remove(kmaps, map); > > - err = maps__insert(kmaps, map); > > - map__put(map); > > + map_ref = map__get(map); > > + maps__remove(kmaps, map_ref); > > + err = maps__insert(kmaps, map_ref); > > + map__put(map_ref); > > map__put(new_map); > > if (err) > > goto out_err; > > -- > > 2.34.1 > > -- - Arnaldo