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 390C7C38A2D for ; Mon, 24 Oct 2022 16:00:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232167AbiJXQAJ (ORCPT ); Mon, 24 Oct 2022 12:00:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38302 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232702AbiJXP7O (ORCPT ); Mon, 24 Oct 2022 11:59:14 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 90D7A23BC6; Mon, 24 Oct 2022 07:54:29 -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 ams.source.kernel.org (Postfix) with ESMTPS id 0CD0AB81132; Mon, 24 Oct 2022 11:46:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 93FC2C433D7; Mon, 24 Oct 2022 11:46:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1666612007; bh=pnOGLgH5gRMhfwXAarsnMQ3g6BWpSzwCy+mhmsk2EMs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=OOPpq5aKDQ88/zqFaqTpYtPq+stRELuPZzsaq3OXBW0/1lq/4asmRAjoc2ezoLGhG R4thXBh7vuS0C1ZTx1+RFAxYJ7HzWqK8uiUB5p6/DLGN+SY+gM7Jd2JJ467lKH63D3 iDxBulvQVtdjgm9rXo+bKNXro8Y5P2wK4Be0nvQYZUO3AvFBs8dphBGvR+VgbF7PRU y19AqoRVZlRBJETLvt97Af2A/4KDHh9NqAHYQIZeq0N31Kn6dT3E7dQfClEm4LHEPG aKpnTlkwi+GXl9yMWNYoqcMEDWl3CP90jZtEPsI8dwge58+A08Ph/PKByRb68lNxEq T2y5XDuU+wF2g== Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id E003B404BE; Mon, 24 Oct 2022 08:46:44 -0300 (-03) Date: Mon, 24 Oct 2022 08:46:44 -0300 From: Arnaldo Carvalho de Melo To: Jiri Olsa , Yang Jihong Cc: peterz@infradead.org, mingo@redhat.com, mark.rutland@arm.com, alexander.shishkin@linux.intel.com, namhyung@kernel.org, adrian.hunter@intel.com, ak@linux.intel.com, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/3] perf daemon: Check err before calling setup_server_config in __cmd_start Message-ID: References: <20221022092735.114967-1-yangjihong1@huawei.com> <20221022092735.114967-2-yangjihong1@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221022092735.114967-2-yangjihong1@huawei.com> X-Url: http://acmel.wordpress.com Precedence: bulk List-ID: X-Mailing-List: linux-perf-users@vger.kernel.org Em Sat, Oct 22, 2022 at 05:27:33PM +0800, Yang Jihong escreveu: > If err!=0 before calling setup_server_config and reconfig==true, > setup_server_config function may return 0 and err becomes 0. > As a result, previous error is overwritten, need to check value of err first. > > Signed-off-by: Yang Jihong > --- > tools/perf/builtin-daemon.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/tools/perf/builtin-daemon.c b/tools/perf/builtin-daemon.c > index 6cb3f6cc36d0..b82bd902602a 100644 > --- a/tools/perf/builtin-daemon.c > +++ b/tools/perf/builtin-daemon.c > @@ -1333,7 +1333,7 @@ static int __cmd_start(struct daemon *daemon, struct option parent_options[], > if (fda.entries[signal_pos].revents & POLLIN) > err = handle_signalfd(daemon) < 0; > > - if (reconfig) > + if (!err && reconfig) > err = setup_server_config(daemon); > } Expanding the context a bit: while (!done && !err) { err = daemon__reconfig(daemon); if (!err && fdarray__poll(&fda, -1)) { bool reconfig = false; if (fda.entries[sock_pos].revents & POLLIN) err = handle_server_socket(daemon, sock_fd); if (fda.entries[file_pos].revents & POLLIN) err = handle_config_changes(daemon, conf_fd, &reconfig); if (fda.entries[signal_pos].revents & POLLIN) err = handle_signalfd(daemon) < 0; if (!err && reconfig) err = setup_server_config(daemon); } } The err you're checking may be the last one, that may have overwritten 'err' from handle_config_changes(), perhaps moving things around helps? I.e.: if (!err && fdarray__poll(&fda, -1)) { bool reconfig = false; if (fda.entries[sock_pos].revents & POLLIN) err = handle_server_socket(daemon, sock_fd); if (fda.entries[signal_pos].revents & POLLIN) err = handle_signalfd(daemon) < 0; if (fda.entries[file_pos].revents & POLLIN) err = handle_config_changes(daemon, conf_fd, &reconfig); if (!err && reconfig) err = setup_server_config(daemon); } ? Jiri? - Arnaldo > } > -- > 2.30.GIT -- - Arnaldo