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 721FC2765D7; Fri, 3 Apr 2026 02:42:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775184146; cv=none; b=Dx8k0fbI5cFG3hZTOhQZaFMdSGhssyYA5qAqkVQfs+nR27IWTEq3BU0Zck3KSfZSZkrjKpvmKQgKlqWPnSZt8hbl2dpQm8ezRnsDY/1fAx3cG313Mp2Rf44g7zxmRqGB66CI24tdhKtGTnkl/ILlbyCwRqmg/BJZj4nn5vb8R3A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775184146; c=relaxed/simple; bh=bEt6923MfGZEPfPIECL9O0QggtDqdLIMKM6x01sodvY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=YBeuSuynAUo8PH6MOb9tBBsn0zOhWz06w5zLIiYaDFZmUfF2N9hPlAstQ9n76//M6Txcovp0riVgnjsp7tTopuxCQeZlSA257WC1BAKATRWT+8kJrb9VOw77gD/83Dp+ig/OvjBGXcnVV60FpnU5ZqC1E9u/aN30TbTu8EgUceA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=DBqO2PfV; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="DBqO2PfV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9A5EAC116C6; Fri, 3 Apr 2026 02:42:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1775184146; bh=bEt6923MfGZEPfPIECL9O0QggtDqdLIMKM6x01sodvY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=DBqO2PfVNs4iQ2jWz01UDtiI8N/B1rFE1JtSfdHE6hfIUWqRNMt625D8+ctPgxiOc JuJt+7shojjBmvZqZ27Bi6vc3Kg4KKdxLlN7Hr72bRJp4AD1+dXK0gUiEjbG9sZQwi Oi5LRcmtALZAxrpVAqDhitgyZyRVhUtRd8X4+MD7dEscJ8c95foLnxoOgXL/2IGzA2 kPp0TycCe/relrbQPnKyd+QRwpiwbYguvxnIs5JHvnHs2ROOfU3Iu/0MABFfLkBHfY FfjG9MQDAvki39lTT464pjwJw5wwFgaXI1pV7LR7vpM5FjHxR3u8zVyP56IBYq18mt aq8xzSm3zeShQ== Date: Thu, 2 Apr 2026 19:42:24 -0700 From: Namhyung Kim To: Ian Rogers Cc: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Alexander Shishkin , Jiri Olsa , Adrian Hunter , James Clark , Swapnil Sapkal , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v1 1/2] perf sched: Avoid segv if tp_handler not set Message-ID: References: <20260321061448.810525-1-irogers@google.com> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Tue, Mar 31, 2026 at 10:59:52PM -0700, Ian Rogers wrote: > On Thu, Mar 26, 2026 at 4:20 PM Namhyung Kim wrote: > > > > On Fri, Mar 20, 2026 at 11:14:47PM -0700, Ian Rogers wrote: > > > Doing a `perf sched record` then `perf sched stats report` crashes as > > > the tp_handler isn't set. Add extra checks that tp_handler is set > > > before accessing through it. > > > > Oh.. unintended use case. :) Probably better to add a dummy handler > > for `perf sched stats report`. > > Perhaps. I'd prefer to land the simpler change as-is. Well.. I guess the dummy handler approach would be simpler and perform better. :) Thanks, Namhyung diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c index d083e2bb770303a4..9fb5447f9014d026 100644 --- a/tools/perf/builtin-sched.c +++ b/tools/perf/builtin-sched.c @@ -4955,6 +4955,7 @@ int cmd_sched(int argc, const char **argv) .switch_event = replay_switch_event, .fork_event = replay_fork_event, }; + struct trace_sched_handler stats_ops = {}; int ret; perf_tool__init(&sched.tool, /*ordered_events=*/true); @@ -5037,6 +5038,7 @@ int cmd_sched(int argc, const char **argv) } else if (!strcmp(argv[0], "stats")) { const char *const stats_subcommands[] = {"record", "report", NULL}; + sched.tp_handler = &stats_ops; argc = parse_options_subcommand(argc, argv, stats_options, stats_subcommands, stats_usage,