From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752203AbdGZOTM (ORCPT ); Wed, 26 Jul 2017 10:19:12 -0400 Received: from mail.kernel.org ([198.145.29.99]:48370 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751578AbdGZOTJ (ORCPT ); Wed, 26 Jul 2017 10:19:09 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0A7BA21C99 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=acme@kernel.org From: Arnaldo Carvalho de Melo To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Arnaldo Carvalho de Melo , Adrian Hunter , David Ahern , Jiri Olsa , Namhyung Kim , Wang Nan Subject: [PATCH 14/40] perf trace: Filter out 'sshd' in the tracer ancestry in syswide tracing Date: Wed, 26 Jul 2017 11:17:04 -0300 Message-Id: <20170726141730.30750-15-acme@kernel.org> X-Mailer: git-send-email 2.9.4 In-Reply-To: <20170726141730.30750-1-acme@kernel.org> References: <20170726141730.30750-1-acme@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arnaldo Carvalho de Melo Avoiding a loop, so now its quite convenient to ssh to a machine and then simply do: # perf trace To trace all syscalls without causing a loop. This was possible using --filter-pids, i.e. once you noticed the loop, get the sshd pid and add it to --filter-pids, restarting the 'perf trace'. Now to figure out how to do that in a X terminal, the other common scenario, which is way more involved, as there are multiple processes communicating to process terminal activity... Using --filter-pids + '-e \!syscall,names,you,dont,need' may be a good approximation when having to do syswide tracing on your workstation. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-68rjeao9wnpylla41htk7xps@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-trace.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 0ba36f08efd8..05d24b6570ee 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -2241,10 +2241,24 @@ static int trace__set_ev_qualifier_filter(struct trace *trace) static int trace__set_filter_loop_pids(struct trace *trace) { - int nr = 1; + unsigned int nr = 1; pid_t pids[32] = { getpid(), }; + struct thread *thread = machine__find_thread(trace->host, pids[0], pids[0]); + + while (thread && nr < ARRAY_SIZE(pids)) { + struct thread *parent = machine__find_thread(trace->host, thread->ppid, thread->ppid); + + if (parent == NULL) + break; + + if (!strcmp(thread__comm_str(parent), "sshd")) { + pids[nr++] = parent->tid; + break; + } + thread = parent; + } return perf_evlist__set_filter_pids(trace->evlist, nr, pids); } -- 2.9.4