From: Tom Zanussi Date: Wed, 28 Mar 2018 20:10:55 +0000 (-0500) Subject: tracing: Add action comparisons when testing matching hist triggers X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=48f794731e4ca7b83b8b22a48bfc8641fa77dd09;p=openwrt%2Fstaging%2Fblogic.git tracing: Add action comparisons when testing matching hist triggers Actions also need to be considered when checking for matching triggers - triggers differing only by action should be allowed, but currently aren't because the matching check ignores the action and erroneously returns -EEXIST. Add and call an actions_match() function to address that. Here's an example using onmatch() actions. The first -EEXIST shouldn't occur because the onmatch() is different in the second wakeup_latency() param. The second -EEXIST shouldn't occur because it's a different action (in this case, it doesn't have an action, so shouldn't be seen as being the same and therefore rejected). In the after case, both are correctly accepted (and trying to add one of them again returns -EEXIST as it should). before: # echo 'wakeup_latency u64 lat; pid_t pid' >> /sys/kernel/debug/tracing/synthetic_events # echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0 if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,next_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,prev_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger -su: echo: write error: File exists # echo 'hist:keys=next_pid if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger -su: echo: write error: File exists after: # echo 'wakeup_latency u64 lat; pid_t pid' >> /sys/kernel/debug/tracing/synthetic_events # echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0 if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,next_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,prev_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger # echo 'hist:keys=next_pid if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger Link: http://lkml.kernel.org/r/a7fd668b87ec10736c8f016ac4279c8480d50c2b.1522256721.git.tom.zanussi@linux.intel.com Tested-by: Masami Hiramatsu Signed-off-by: Tom Zanussi Signed-off-by: Steven Rostedt (VMware) --- diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index d867502a56ba..6114939f065a 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -4364,6 +4364,53 @@ static void print_onmatch_spec(struct seq_file *m, seq_puts(m, ")"); } +static bool actions_match(struct hist_trigger_data *hist_data, + struct hist_trigger_data *hist_data_test) +{ + unsigned int i, j; + + if (hist_data->n_actions != hist_data_test->n_actions) + return false; + + for (i = 0; i < hist_data->n_actions; i++) { + struct action_data *data = hist_data->actions[i]; + struct action_data *data_test = hist_data_test->actions[i]; + + if (data->fn != data_test->fn) + return false; + + if (data->n_params != data_test->n_params) + return false; + + for (j = 0; j < data->n_params; j++) { + if (strcmp(data->params[j], data_test->params[j]) != 0) + return false; + } + + if (data->fn == action_trace) { + if (strcmp(data->onmatch.synth_event_name, + data_test->onmatch.synth_event_name) != 0) + return false; + if (strcmp(data->onmatch.match_event_system, + data_test->onmatch.match_event_system) != 0) + return false; + if (strcmp(data->onmatch.match_event, + data_test->onmatch.match_event) != 0) + return false; + } else if (data->fn == onmax_save) { + if (strcmp(data->onmax.var_str, + data_test->onmax.var_str) != 0) + return false; + if (strcmp(data->onmax.fn_name, + data_test->onmax.fn_name) != 0) + return false; + } + } + + return true; +} + + static void print_actions_spec(struct seq_file *m, struct hist_trigger_data *hist_data) { @@ -5174,6 +5221,9 @@ static bool hist_trigger_match(struct event_trigger_data *data, (strcmp(data->filter_str, data_test->filter_str) != 0)) return false; + if (!actions_match(hist_data, hist_data_test)) + return false; + return true; }