From 266fa2b22294909ddf6e7d2f8acfe07adf9fd978 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Thu, 24 Sep 2015 11:24:18 -0300 Subject: [PATCH] perf probe: Use existing routine to look for a kernel module by dso->short_name We have map_groups__find_by_name() to look at the list of modules that are in place for a given machine, so use it instead of traversing the machine dso list, which also includes DSOs for userspace. When merging the user and kernel DSO lists a bug was introduced where 'perf probe' stopped being able to add probes to modules using its short name: # perf probe -m usbnet --add usbnet_start_xmit usbnet_start_xmit is out of .text, skip it. Error: Failed to add events. # With this fix it works again: # perf probe -m usbnet --add usbnet_start_xmit Added new event: probe:usbnet_start_xmit (on usbnet_start_xmit in usbnet) You can now use it in all perf tools, such as: perf record -e probe:usbnet_start_xmit -aR sleep 1 # Reported-by: Wang Nan Acked-by: Masami Hiramatsu Cc: Adrian Hunter Cc: Borislav Petkov Cc: David Ahern Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Namhyung Kim Cc: Stephane Eranian Fixes: 3d39ac538629 ("perf machine: No need to have two DSOs lists") Link: http://lkml.kernel.org/r/20150924015008.GE1897@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/probe-event.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index eb5f18b75402..c6f9af78f6f5 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -270,12 +270,13 @@ static int kernel_get_module_dso(const char *module, struct dso **pdso) int ret = 0; if (module) { - list_for_each_entry(dso, &host_machine->dsos.head, node) { - if (!dso->kernel) - continue; - if (strncmp(dso->short_name + 1, module, - dso->short_name_len - 2) == 0) - goto found; + char module_name[128]; + + snprintf(module_name, sizeof(module_name), "[%s]", module); + map = map_groups__find_by_name(&host_machine->kmaps, MAP__FUNCTION, module_name); + if (map) { + dso = map->dso; + goto found; } pr_debug("Failed to find module %s.\n", module); return -ENOENT; -- 2.34.1