From 9d7b45c5721dfd524666bc1f07cf7d0855edb4d5 Mon Sep 17 00:00:00 2001 From: He Kuang Date: Mon, 13 Apr 2015 19:41:28 +0800 Subject: [PATCH] perf probe: Set retprobe flag when probe in address-based alternative mode When perf probe searched in a debuginfo file and failed, it tried with an alternative, in function get_alternative_probe_event(): memcpy(tmp, &pev->point, sizeof(*tmp)); memset(&pev->point, 0, sizeof(pev->point)); In this case, it drops the retprobe flag and forgets to set it back in find_alternative_probe_point(), so the problem occurs. Can be reproduced as following: $ perf probe -v -k vmlinux --add='sys_write%return' ... Added new event: Writing event: p:probe/sys_write _stext+1584952 probe:sys_write (on sys_write%return) $ cat /sys/kernel/debug/tracing/kprobe_events p:probe/sys_write _stext+1584952 After this patch: $ perf probe -v -k vmlinux --add='sys_write%return' Added new event: Writing event: r:probe/sys_write SyS_write+0 probe:sys_write (on sys_write%return) $ cat /sys/kernel/debug/tracing/kprobe_events r:probe/sys_write SyS_write Signed-off-by: He Kuang Tested-by: Arnaldo Carvalho de Melo Acked-by: Masami Hiramatsu Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Wang Nan Link: http://lkml.kernel.org/r/1428925290-5623-1-git-send-email-hekuang@huawei.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/probe-event.c | 1 + 1 file changed, 1 insertion(+) diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index 30545ce2c712..5483d98236d3 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -332,6 +332,7 @@ static int find_alternative_probe_point(struct debuginfo *dinfo, else { result->offset += pp->offset; result->line += pp->line; + result->retprobe = pp->retprobe; ret = 0; }