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-rw-r--r--kernel/trace/trace_events_hist.c53
1 files changed, 38 insertions, 15 deletions
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 2e88c9805f4b..5b4e04780411 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -476,11 +476,12 @@ struct action_data {
* 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.
+ * var_ref_vals array. This var_ref_idx array is an array of
+ * indices into the var_ref_vals array, one for each synthetic
+ * event param, and is passed to the synthetic event
+ * invocation.
*/
- unsigned int var_ref_idx;
+ unsigned int var_ref_idx[TRACING_MAP_VARS_MAX];
struct synth_event *synth_event;
bool use_trace_keyword;
char *synth_event_name;
@@ -884,14 +885,14 @@ static struct trace_event_functions synth_event_funcs = {
static notrace void trace_event_raw_event_synth(void *__data,
u64 *var_ref_vals,
- unsigned int var_ref_idx)
+ unsigned int *var_ref_idx)
{
struct trace_event_file *trace_file = __data;
struct synth_trace_event *entry;
struct trace_event_buffer fbuffer;
struct trace_buffer *buffer;
struct synth_event *event;
- unsigned int i, n_u64;
+ unsigned int i, n_u64, val_idx;
int fields_size = 0;
event = trace_file->event_call->data;
@@ -914,15 +915,16 @@ static notrace void trace_event_raw_event_synth(void *__data,
goto out;
for (i = 0, n_u64 = 0; i < event->n_fields; i++) {
+ val_idx = var_ref_idx[i];
if (event->fields[i]->is_string) {
- char *str_val = (char *)(long)var_ref_vals[var_ref_idx + i];
+ char *str_val = (char *)(long)var_ref_vals[val_idx];
char *str_field = (char *)&entry->fields[n_u64];
strscpy(str_field, str_val, STR_VAR_LEN_MAX);
n_u64 += STR_VAR_LEN_MAX / sizeof(u64);
} else {
struct synth_field *field = event->fields[i];
- u64 val = var_ref_vals[var_ref_idx + i];
+ u64 val = var_ref_vals[val_idx];
switch (field->size) {
case 1:
@@ -1122,10 +1124,10 @@ static struct tracepoint *alloc_synth_tracepoint(char *name)
}
typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals,
- unsigned int var_ref_idx);
+ unsigned int *var_ref_idx);
static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals,
- unsigned int var_ref_idx)
+ unsigned int *var_ref_idx)
{
struct tracepoint *tp = event->tp;
@@ -3506,6 +3508,22 @@ static int init_var_ref(struct hist_field *ref_field,
goto out;
}
+static int find_var_ref_idx(struct hist_trigger_data *hist_data,
+ struct hist_field *var_field)
+{
+ struct hist_field *ref_field;
+ int i;
+
+ for (i = 0; i < hist_data->n_var_refs; i++) {
+ ref_field = hist_data->var_refs[i];
+ if (ref_field->var.idx == var_field->var.idx &&
+ ref_field->var.hist_data == var_field->hist_data)
+ return i;
+ }
+
+ return -ENOENT;
+}
+
/**
* create_var_ref - Create a variable reference and attach it to trigger
* @hist_data: The trigger that will be referencing the variable
@@ -5071,11 +5089,11 @@ static int trace_action_create(struct hist_trigger_data *hist_data,
struct trace_array *tr = hist_data->event_file->tr;
char *event_name, *param, *system = NULL;
struct hist_field *hist_field, *var_ref;
- unsigned int i, var_ref_idx;
+ unsigned int i;
unsigned int field_pos = 0;
struct synth_event *event;
char *synth_event_name;
- int ret = 0;
+ int var_ref_idx, ret = 0;
lockdep_assert_held(&event_mutex);
@@ -5092,8 +5110,6 @@ static int trace_action_create(struct hist_trigger_data *hist_data,
event->ref++;
- var_ref_idx = hist_data->n_var_refs;
-
for (i = 0; i < data->n_params; i++) {
char *p;
@@ -5142,6 +5158,14 @@ static int trace_action_create(struct hist_trigger_data *hist_data,
goto err;
}
+ var_ref_idx = find_var_ref_idx(hist_data, var_ref);
+ if (WARN_ON(var_ref_idx < 0)) {
+ ret = var_ref_idx;
+ goto err;
+ }
+
+ data->var_ref_idx[i] = var_ref_idx;
+
field_pos++;
kfree(p);
continue;
@@ -5160,7 +5184,6 @@ static int trace_action_create(struct hist_trigger_data *hist_data,
}
data->synth_event = event;
- data->var_ref_idx = var_ref_idx;
out:
return ret;
err: