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-rw-r--r--kernel/trace/trace.c12
-rw-r--r--kernel/trace/trace_events_hist.c103
2 files changed, 63 insertions, 52 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index b583ff7656bb..b477926ac3bc 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4700,6 +4700,7 @@ static const char readme_msg[] =
"\t [:size=#entries]\n"
"\t [:pause][:continue][:clear]\n"
"\t [:name=histname1]\n"
+ "\t [:<handler>.<action>]\n"
"\t [if <filter>]\n\n"
"\t When a matching event is hit, an entry is added to a hash\n"
"\t table using the key(s) and value(s) named, and the value of a\n"
@@ -4741,7 +4742,16 @@ static const char readme_msg[] =
"\t The enable_hist and disable_hist triggers can be used to\n"
"\t have one event conditionally start and stop another event's\n"
"\t already-attached hist trigger. The syntax is analagous to\n"
- "\t the enable_event and disable_event triggers.\n"
+ "\t the enable_event and disable_event triggers.\n\n"
+ "\t Hist trigger handlers and actions are executed whenever a\n"
+ "\t a histogram entry is added or updated. They take the form:\n\n"
+ "\t <handler>.<action>\n\n"
+ "\t The available handlers are:\n\n"
+ "\t onmatch(matching.event) - invoke on addition or update\n"
+ "\t onmax(var) - invoke if var exceeds current max\n\n"
+ "\t The available actions are:\n\n"
+ "\t <synthetic_event>(param list) - generate synthetic event\n"
+ "\t save(field,...) - save current event fields\n"
#endif
;
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index dfaaad582797..0b843ecef547 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -405,21 +405,22 @@ struct action_data {
unsigned int n_params;
char *params[SYNTH_FIELDS_MAX];
+ /*
+ * When a histogram trigger is hit, the values of any
+ * references to variables, including variables being passed
+ * as parameters to synthetic events, are collected into a
+ * var_ref_vals array. This var_ref_idx is the index of the
+ * first param in the array to be passed to the synthetic
+ * event invocation.
+ */
+ unsigned int var_ref_idx;
+ struct synth_event *synth_event;
+
union {
struct {
- /*
- * When a histogram trigger is hit, the values of any
- * references to variables, including variables being passed
- * as parameters to synthetic events, are collected into a
- * var_ref_vals array. This var_ref_idx is the index of the
- * first param in the array to be passed to the synthetic
- * event invocation.
- */
- unsigned int var_ref_idx;
- char *match_event;
- char *match_event_system;
- struct synth_event *synth_event;
- } onmatch;
+ char *event;
+ char *event_system;
+ } match_data;
struct {
char *var_str;
@@ -1093,9 +1094,9 @@ static void action_trace(struct hist_trigger_data *hist_data,
struct ring_buffer_event *rbe, void *key,
struct action_data *data, u64 *var_ref_vals)
{
- struct synth_event *event = data->onmatch.synth_event;
+ struct synth_event *event = data->synth_event;
- trace_synth(event, var_ref_vals, data->onmatch.var_ref_idx);
+ trace_synth(event, var_ref_vals, data->var_ref_idx);
}
struct hist_var_data {
@@ -1657,8 +1658,8 @@ find_match_var(struct hist_trigger_data *hist_data, char *var_name)
struct action_data *data = hist_data->actions[i];
if (data->handler == HANDLER_ONMATCH) {
- char *system = data->onmatch.match_event_system;
- char *event_name = data->onmatch.match_event;
+ char *system = data->match_data.event_system;
+ char *event_name = data->match_data.event;
file = find_var_file(tr, system, event_name, var_name);
if (!file)
@@ -3425,22 +3426,33 @@ static void onmax_save(struct hist_trigger_data *hist_data,
update_max_vars(hist_data, elt, rbe, rec);
}
-static void onmax_destroy(struct action_data *data)
+static void action_data_destroy(struct action_data *data)
{
unsigned int i;
- destroy_hist_field(data->onmax.max_var, 0);
- destroy_hist_field(data->onmax.var, 0);
+ lockdep_assert_held(&event_mutex);
- kfree(data->onmax.var_str);
kfree(data->action_name);
for (i = 0; i < data->n_params; i++)
kfree(data->params[i]);
+ if (data->synth_event)
+ data->synth_event->ref--;
+
kfree(data);
}
+static void onmax_destroy(struct action_data *data)
+{
+ destroy_hist_field(data->onmax.max_var, 0);
+ destroy_hist_field(data->onmax.var, 0);
+
+ kfree(data->onmax.var_str);
+
+ action_data_destroy(data);
+}
+
static int action_create(struct hist_trigger_data *hist_data,
struct action_data *data);
@@ -3620,21 +3632,10 @@ static struct action_data *onmax_parse(char *str, enum handler_id handler)
static void onmatch_destroy(struct action_data *data)
{
- unsigned int i;
-
- lockdep_assert_held(&event_mutex);
+ kfree(data->match_data.event);
+ kfree(data->match_data.event_system);
- kfree(data->onmatch.match_event);
- kfree(data->onmatch.match_event_system);
- kfree(data->action_name);
-
- for (i = 0; i < data->n_params; i++)
- kfree(data->params[i]);
-
- if (data->onmatch.synth_event)
- data->onmatch.synth_event->ref--;
-
- kfree(data);
+ action_data_destroy(data);
}
static void destroy_field_var(struct field_var *field_var)
@@ -3695,8 +3696,8 @@ trace_action_find_var(struct hist_trigger_data *hist_data,
hist_field = find_target_event_var(hist_data, system, event, var);
if (!hist_field) {
if (!system && data->handler == HANDLER_ONMATCH) {
- system = data->onmatch.match_event_system;
- event = data->onmatch.match_event;
+ system = data->match_data.event_system;
+ event = data->match_data.event;
}
hist_field = find_event_var(hist_data, system, event, var);
@@ -3735,8 +3736,8 @@ trace_action_create_field_var(struct hist_trigger_data *hist_data,
* event.
*/
if (!system && data->handler == HANDLER_ONMATCH) {
- system = data->onmatch.match_event_system;
- event = data->onmatch.match_event;
+ system = data->match_data.event_system;
+ event = data->match_data.event;
}
/*
@@ -3846,8 +3847,8 @@ static int trace_action_create(struct hist_trigger_data *hist_data,
goto err;
}
- data->onmatch.synth_event = event;
- data->onmatch.var_ref_idx = var_ref_idx;
+ data->synth_event = event;
+ data->var_ref_idx = var_ref_idx;
out:
return ret;
err:
@@ -3933,14 +3934,14 @@ static struct action_data *onmatch_parse(struct trace_array *tr, char *str)
goto free;
}
- data->onmatch.match_event = kstrdup(match_event, GFP_KERNEL);
- if (!data->onmatch.match_event) {
+ data->match_data.event = kstrdup(match_event, GFP_KERNEL);
+ if (!data->match_data.event) {
ret = -ENOMEM;
goto free;
}
- data->onmatch.match_event_system = kstrdup(match_event_system, GFP_KERNEL);
- if (!data->onmatch.match_event_system) {
+ data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL);
+ if (!data->match_data.event_system) {
ret = -ENOMEM;
goto free;
}
@@ -4511,8 +4512,8 @@ static void print_onmatch_spec(struct seq_file *m,
struct hist_trigger_data *hist_data,
struct action_data *data)
{
- seq_printf(m, ":onmatch(%s.%s).", data->onmatch.match_event_system,
- data->onmatch.match_event);
+ seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system,
+ data->match_data.event);
seq_printf(m, "%s(", data->action_name);
@@ -4550,11 +4551,11 @@ static bool actions_match(struct hist_trigger_data *hist_data,
return false;
if (data->handler == HANDLER_ONMATCH) {
- if (strcmp(data->onmatch.match_event_system,
- data_test->onmatch.match_event_system) != 0)
+ if (strcmp(data->match_data.event_system,
+ data_test->match_data.event_system) != 0)
return false;
- if (strcmp(data->onmatch.match_event,
- data_test->onmatch.match_event) != 0)
+ if (strcmp(data->match_data.event,
+ data_test->match_data.event) != 0)
return false;
} else if (data->handler == HANDLER_ONMAX) {
if (strcmp(data->onmax.var_str,
generated by cgit (git 2.34.1) at 2025-03-31 16:38:29 +0000