From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2F969156EB for ; Mon, 5 Jun 2023 13:47:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6FC7EC433D2; Mon, 5 Jun 2023 13:47:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1685972845; bh=OHXz1OKPeLqjsvKzYaWmG3JfzQJvaSjKi8PweDxzETQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=IFLdiaFa6dJxabXAjCiytv0nBxnWvbaR+SfmFBkl+itxfKR10Qii37ivsTQFZCoXd DfqDLBMg16twIFpPieJu3aNZn+5MRrc5OLFUMcDFjcSSIcFulAUd0BKdIiKOhcPJmM R49TQlmdInwA6JQHNxk+FvvIRweuHmW3lRKG0v9SjMMzlaW9V3kBg5pbnlNxPfF75j owdIGTbC1ib2hJmqKWNuEz0csqyVMYghBjayulIL9qPMcj2LU8A8ihfNoT4YifWuWM Aep7EunZs6Tw8JLFIKeMzARgi5UzO6rzFy0aMdnZSFpc+uzB9wT5Wq6PE7W3/p4NQ1 YJMXAo4YhBztQ== Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id 0C32940692; Mon, 5 Jun 2023 10:47:23 -0300 (-03) Date: Mon, 5 Jun 2023 10:47:22 -0300 From: Arnaldo Carvalho de Melo To: Eduard Zingerman Cc: Arnaldo Carvalho de Melo , dwarves@vger.kernel.org, bpf@vger.kernel.org, kernel-team@fb.com, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, yhs@fb.com, mykolal@fb.com Subject: Re: [PATCH dwarves] pahole: avoid adding same struct structure to two rb trees Message-ID: References: <20230525235949.2978377-1-eddyz87@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Url: http://acmel.wordpress.com Em Fri, Jun 02, 2023 at 09:08:51PM +0300, Eduard Zingerman escreveu: > On Fri, 2023-06-02 at 15:04 -0300, Arnaldo Carvalho de Melo wrote: > > Em Fri, Jun 02, 2023 at 04:52:40PM +0300, Eduard Zingerman escreveu: > > > Right, you are correct. > > > The 'structures__tree = RB_ROOT' part is still necessary, though. > > > If you are ok with overall structure of the patch I can resend it w/o bzero(). > > Humm, so basically this boils down to the following patch? > > +++ b/pahole.c > > @@ -674,7 +674,12 @@ static void print_ordered_classes(void) > > __print_ordered_classes(&structures__tree); > > } else { > > struct rb_root resorted = RB_ROOT; > > - > > +#ifdef DEBUG_CHECK_LEAKS > > + // We'll delete structures from structures__tree, since we're > > + // adding them to ther resorted list, better not keep > > + // references there. > > + structures__tree = RB_ROOT; > > +#endif > But __structures__delete iterates over structures__tree, > so it won't delete anything if code like this, right? > > resort_classes(&resorted, &structures__list); > > __print_ordered_classes(&resorted); > > } Yeah, I tried to be minimalistic, my version avoids the crash, but defeats the DEBUG_CHECK_LEAKS purpose :-\ How about: diff --git a/pahole.c b/pahole.c index 6fc4ed6a721b97ab..e843999fde2a8a37 100644 --- a/pahole.c +++ b/pahole.c @@ -673,10 +673,10 @@ static void print_ordered_classes(void) if (!need_resort) { __print_ordered_classes(&structures__tree); } else { - struct rb_root resorted = RB_ROOT; + structures__tree = RB_ROOT; - resort_classes(&resorted, &structures__list); - __print_ordered_classes(&resorted); + resort_classes(&structures__tree, &structures__list); + __print_ordered_classes(&structures__tree); } }