[PATCH 3/4] tracing: Add action comparisons when testing matching hist triggers

From: Tom Zanussi
Date: Wed Mar 28 2018 - 16:11:20 EST


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.

Signed-off-by: Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx>
---
kernel/trace/trace_events_hist.c | 50 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 50 insertions(+)

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 468e43f..ae84470 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -4363,6 +4363,53 @@ 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)
{
@@ -5173,6 +5220,9 @@ 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;
}

--
1.9.3