summaryrefslogtreecommitdiff
path: root/tools/perf
diff options
context:
space:
mode:
authorArnaldo Carvalho de Melo <acme@redhat.com>2017-07-20 17:32:05 +0300
committerArnaldo Carvalho de Melo <acme@redhat.com>2017-07-20 21:16:25 +0300
commit082ab9a18e532864d1ceecfb50221df62b1d5a92 (patch)
tree5ff262d2099de106864d771940a4debdb1fc8a01 /tools/perf
parentdd1a50377c92321f78fa4d0601bb4d88d88670ab (diff)
downloadlinux-082ab9a18e532864d1ceecfb50221df62b1d5a92.tar.xz
perf trace: Filter out 'sshd' in the tracer ancestry in syswide tracing
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 <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-68rjeao9wnpylla41htk7xps@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf')
-rw-r--r--tools/perf/builtin-trace.c16
1 files changed, 15 insertions, 1 deletions
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 @@ out_enomem:
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);
}