tracing: Add hist trigger snapshot() action
Add support for hist:handlerXXX($var).snapshot(), which will take a snapshot of the current trace buffer whenever handlerXXX is hit. As a first user, this also adds snapshot() action support for the onmax() handler i.e. hist:onmax($var).snapshot(). Also, the hist trigger key printing is moved into a separate function so the snapshot() action can print a histogram key outside the histogram display - add and use hist_trigger_print_key() for that purpose. Link: http://lkml.kernel.org/r/2f1a952c0dcd8aca8702ce81269581a692396d45.1550100284.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>hifive-unleashed-5.1
Tom Zanussi
Steven Rostedt (VMware)
parent
a35873a099
commit
a3785b7eca
|
|
@ -4919,6 +4919,9 @@ static const char readme_msg[] =
|
|||
"\t The available actions are:\n\n"
|
||||
"\t <synthetic_event>(param list) - generate synthetic event\n"
|
||||
"\t save(field,...) - save current event fields\n"
|
||||
#ifdef CONFIG_TRACER_SNAPSHOT
|
||||
"\t snapshot() - snapshot the trace buffer\n"
|
||||
#endif
|
||||
#endif
|
||||
;
|
||||
|
||||
|
|
|
|||
|
|
@ -396,6 +396,7 @@ enum handler_id {
|
|||
enum action_id {
|
||||
ACTION_SAVE = 1,
|
||||
ACTION_TRACE,
|
||||
ACTION_SNAPSHOT,
|
||||
};
|
||||
|
||||
struct action_data {
|
||||
|
|
@ -454,6 +455,83 @@ struct action_data {
|
|||
};
|
||||
};
|
||||
|
||||
struct track_data {
|
||||
u64 track_val;
|
||||
bool updated;
|
||||
|
||||
unsigned int key_len;
|
||||
void *key;
|
||||
struct tracing_map_elt elt;
|
||||
|
||||
struct action_data *action_data;
|
||||
struct hist_trigger_data *hist_data;
|
||||
};
|
||||
|
||||
struct hist_elt_data {
|
||||
char *comm;
|
||||
u64 *var_ref_vals;
|
||||
char *field_var_str[SYNTH_FIELDS_MAX];
|
||||
};
|
||||
|
||||
struct snapshot_context {
|
||||
struct tracing_map_elt *elt;
|
||||
void *key;
|
||||
};
|
||||
|
||||
static void track_data_free(struct track_data *track_data)
|
||||
{
|
||||
struct hist_elt_data *elt_data;
|
||||
|
||||
if (!track_data)
|
||||
return;
|
||||
|
||||
kfree(track_data->key);
|
||||
|
||||
elt_data = track_data->elt.private_data;
|
||||
if (elt_data) {
|
||||
kfree(elt_data->comm);
|
||||
kfree(elt_data);
|
||||
}
|
||||
|
||||
kfree(track_data);
|
||||
}
|
||||
|
||||
static struct track_data *track_data_alloc(unsigned int key_len,
|
||||
struct action_data *action_data,
|
||||
struct hist_trigger_data *hist_data)
|
||||
{
|
||||
struct track_data *data = kzalloc(sizeof(*data), GFP_KERNEL);
|
||||
struct hist_elt_data *elt_data;
|
||||
|
||||
if (!data)
|
||||
return ERR_PTR(-ENOMEM);
|
||||
|
||||
data->key = kzalloc(key_len, GFP_KERNEL);
|
||||
if (!data->key) {
|
||||
track_data_free(data);
|
||||
return ERR_PTR(-ENOMEM);
|
||||
}
|
||||
|
||||
data->key_len = key_len;
|
||||
data->action_data = action_data;
|
||||
data->hist_data = hist_data;
|
||||
|
||||
elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL);
|
||||
if (!elt_data) {
|
||||
track_data_free(data);
|
||||
return ERR_PTR(-ENOMEM);
|
||||
}
|
||||
data->elt.private_data = elt_data;
|
||||
|
||||
elt_data->comm = kzalloc(TASK_COMM_LEN, GFP_KERNEL);
|
||||
if (!elt_data->comm) {
|
||||
track_data_free(data);
|
||||
return ERR_PTR(-ENOMEM);
|
||||
}
|
||||
|
||||
return data;
|
||||
}
|
||||
|
||||
static char last_hist_cmd[MAX_FILTER_STR_VAL];
|
||||
static char hist_err_str[MAX_FILTER_STR_VAL];
|
||||
|
||||
|
|
@ -1726,12 +1804,6 @@ static struct hist_field *find_event_var(struct hist_trigger_data *hist_data,
|
|||
return hist_field;
|
||||
}
|
||||
|
||||
struct hist_elt_data {
|
||||
char *comm;
|
||||
u64 *var_ref_vals;
|
||||
char *field_var_str[SYNTH_FIELDS_MAX];
|
||||
};
|
||||
|
||||
static u64 hist_field_var_ref(struct hist_field *hist_field,
|
||||
struct tracing_map_elt *elt,
|
||||
struct ring_buffer_event *rbe,
|
||||
|
|
@ -3452,6 +3524,112 @@ static bool check_track_val(struct tracing_map_elt *elt,
|
|||
return data->track_data.check_val(track_val, var_val);
|
||||
}
|
||||
|
||||
#ifdef CONFIG_TRACER_SNAPSHOT
|
||||
static bool cond_snapshot_update(struct trace_array *tr, void *cond_data)
|
||||
{
|
||||
/* called with tr->max_lock held */
|
||||
struct track_data *track_data = tr->cond_snapshot->cond_data;
|
||||
struct hist_elt_data *elt_data, *track_elt_data;
|
||||
struct snapshot_context *context = cond_data;
|
||||
u64 track_val;
|
||||
|
||||
if (!track_data)
|
||||
return false;
|
||||
|
||||
track_val = get_track_val(track_data->hist_data, context->elt,
|
||||
track_data->action_data);
|
||||
|
||||
track_data->track_val = track_val;
|
||||
memcpy(track_data->key, context->key, track_data->key_len);
|
||||
|
||||
elt_data = context->elt->private_data;
|
||||
track_elt_data = track_data->elt.private_data;
|
||||
if (elt_data->comm)
|
||||
memcpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN);
|
||||
|
||||
track_data->updated = true;
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
static void save_track_data_snapshot(struct hist_trigger_data *hist_data,
|
||||
struct tracing_map_elt *elt, void *rec,
|
||||
struct ring_buffer_event *rbe, void *key,
|
||||
struct action_data *data,
|
||||
u64 *var_ref_vals)
|
||||
{
|
||||
struct trace_event_file *file = hist_data->event_file;
|
||||
struct snapshot_context context;
|
||||
|
||||
context.elt = elt;
|
||||
context.key = key;
|
||||
|
||||
tracing_snapshot_cond(file->tr, &context);
|
||||
}
|
||||
|
||||
static void hist_trigger_print_key(struct seq_file *m,
|
||||
struct hist_trigger_data *hist_data,
|
||||
void *key,
|
||||
struct tracing_map_elt *elt);
|
||||
|
||||
static struct action_data *snapshot_action(struct hist_trigger_data *hist_data)
|
||||
{
|
||||
unsigned int i;
|
||||
|
||||
if (!hist_data->n_actions)
|
||||
return NULL;
|
||||
|
||||
for (i = 0; i < hist_data->n_actions; i++) {
|
||||
struct action_data *data = hist_data->actions[i];
|
||||
|
||||
if (data->action == ACTION_SNAPSHOT)
|
||||
return data;
|
||||
}
|
||||
|
||||
return NULL;
|
||||
}
|
||||
|
||||
static void track_data_snapshot_print(struct seq_file *m,
|
||||
struct hist_trigger_data *hist_data)
|
||||
{
|
||||
struct trace_event_file *file = hist_data->event_file;
|
||||
struct track_data *track_data;
|
||||
struct action_data *action;
|
||||
|
||||
track_data = tracing_cond_snapshot_data(file->tr);
|
||||
if (!track_data)
|
||||
return;
|
||||
|
||||
if (!track_data->updated)
|
||||
return;
|
||||
|
||||
action = snapshot_action(hist_data);
|
||||
if (!action)
|
||||
return;
|
||||
|
||||
seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n");
|
||||
seq_printf(m, "\ttriggering value { %s(%s) }: %10llu",
|
||||
action->handler == HANDLER_ONMAX ? "onmax" : "onchange",
|
||||
action->track_data.var_str, track_data->track_val);
|
||||
|
||||
seq_puts(m, "\ttriggered by event with key: ");
|
||||
hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt);
|
||||
seq_putc(m, '\n');
|
||||
}
|
||||
#else
|
||||
static bool cond_snapshot_update(struct trace_array *tr, void *cond_data)
|
||||
{
|
||||
return false;
|
||||
}
|
||||
static void save_track_data_snapshot(struct hist_trigger_data *hist_data,
|
||||
struct tracing_map_elt *elt, void *rec,
|
||||
struct ring_buffer_event *rbe, void *key,
|
||||
struct action_data *data,
|
||||
u64 *var_ref_vals) {}
|
||||
static void track_data_snapshot_print(struct seq_file *m,
|
||||
struct hist_trigger_data *hist_data) {}
|
||||
#endif /* CONFIG_TRACER_SNAPSHOT */
|
||||
|
||||
static void track_data_print(struct seq_file *m,
|
||||
struct hist_trigger_data *hist_data,
|
||||
struct tracing_map_elt *elt,
|
||||
|
|
@ -3463,6 +3641,9 @@ static void track_data_print(struct seq_file *m,
|
|||
if (data->handler == HANDLER_ONMAX)
|
||||
seq_printf(m, "\n\tmax: %10llu", track_val);
|
||||
|
||||
if (data->action == ACTION_SNAPSHOT)
|
||||
return;
|
||||
|
||||
for (i = 0; i < hist_data->n_save_vars; i++) {
|
||||
struct hist_field *save_val = hist_data->save_vars[i]->val;
|
||||
struct hist_field *save_var = hist_data->save_vars[i]->var;
|
||||
|
|
@ -3513,9 +3694,21 @@ static void action_data_destroy(struct action_data *data)
|
|||
static void track_data_destroy(struct hist_trigger_data *hist_data,
|
||||
struct action_data *data)
|
||||
{
|
||||
struct trace_event_file *file = hist_data->event_file;
|
||||
|
||||
destroy_hist_field(data->track_data.track_var, 0);
|
||||
destroy_hist_field(data->track_data.var_ref, 0);
|
||||
|
||||
if (data->action == ACTION_SNAPSHOT) {
|
||||
struct track_data *track_data;
|
||||
|
||||
track_data = tracing_cond_snapshot_data(file->tr);
|
||||
if (track_data && track_data->hist_data == hist_data) {
|
||||
tracing_snapshot_cond_disable(file->tr);
|
||||
track_data_free(track_data);
|
||||
}
|
||||
}
|
||||
|
||||
kfree(data->track_data.var_str);
|
||||
|
||||
action_data_destroy(data);
|
||||
|
|
@ -3646,6 +3839,26 @@ static int action_parse(char *str, struct action_data *data,
|
|||
data->track_data.save_data = save_track_data_vars;
|
||||
data->fn = ontrack_action;
|
||||
data->action = ACTION_SAVE;
|
||||
} else if (str_has_prefix(action_name, "snapshot")) {
|
||||
char *params = strsep(&str, ")");
|
||||
|
||||
if (!str) {
|
||||
hist_err("action parsing: No closing paren found: %s", params);
|
||||
ret = -EINVAL;
|
||||
goto out;
|
||||
}
|
||||
|
||||
if (handler == HANDLER_ONMAX)
|
||||
data->track_data.check_val = check_track_val_max;
|
||||
else {
|
||||
hist_err("action parsing: Handler doesn't support action: ", action_name);
|
||||
ret = -EINVAL;
|
||||
goto out;
|
||||
}
|
||||
|
||||
data->track_data.save_data = save_track_data_snapshot;
|
||||
data->fn = ontrack_action;
|
||||
data->action = ACTION_SNAPSHOT;
|
||||
} else {
|
||||
char *params = strsep(&str, ")");
|
||||
|
||||
|
|
@ -3942,6 +4155,8 @@ static int trace_action_create(struct hist_trigger_data *hist_data,
|
|||
static int action_create(struct hist_trigger_data *hist_data,
|
||||
struct action_data *data)
|
||||
{
|
||||
struct trace_event_file *file = hist_data->event_file;
|
||||
struct track_data *track_data;
|
||||
struct field_var *field_var;
|
||||
unsigned int i;
|
||||
char *param;
|
||||
|
|
@ -3950,6 +4165,21 @@ static int action_create(struct hist_trigger_data *hist_data,
|
|||
if (data->action == ACTION_TRACE)
|
||||
return trace_action_create(hist_data, data);
|
||||
|
||||
if (data->action == ACTION_SNAPSHOT) {
|
||||
track_data = track_data_alloc(hist_data->key_size, data, hist_data);
|
||||
if (IS_ERR(track_data)) {
|
||||
ret = PTR_ERR(track_data);
|
||||
goto out;
|
||||
}
|
||||
|
||||
ret = tracing_snapshot_cond_enable(file->tr, track_data,
|
||||
cond_snapshot_update);
|
||||
if (ret)
|
||||
track_data_free(track_data);
|
||||
|
||||
goto out;
|
||||
}
|
||||
|
||||
if (data->action == ACTION_SAVE) {
|
||||
if (hist_data->n_save_vars) {
|
||||
ret = -EEXIST;
|
||||
|
|
@ -4552,6 +4782,9 @@ static void print_actions(struct seq_file *m,
|
|||
for (i = 0; i < hist_data->n_actions; i++) {
|
||||
struct action_data *data = hist_data->actions[i];
|
||||
|
||||
if (data->action == ACTION_SNAPSHOT)
|
||||
continue;
|
||||
|
||||
if (data->handler == HANDLER_ONMAX)
|
||||
track_data_print(m, hist_data, elt, data);
|
||||
}
|
||||
|
|
@ -4946,10 +5179,10 @@ static void hist_trigger_stacktrace_print(struct seq_file *m,
|
|||
}
|
||||
}
|
||||
|
||||
static void
|
||||
hist_trigger_entry_print(struct seq_file *m,
|
||||
struct hist_trigger_data *hist_data, void *key,
|
||||
struct tracing_map_elt *elt)
|
||||
static void hist_trigger_print_key(struct seq_file *m,
|
||||
struct hist_trigger_data *hist_data,
|
||||
void *key,
|
||||
struct tracing_map_elt *elt)
|
||||
{
|
||||
struct hist_field *key_field;
|
||||
char str[KSYM_SYMBOL_LEN];
|
||||
|
|
@ -5025,6 +5258,17 @@ hist_trigger_entry_print(struct seq_file *m,
|
|||
seq_puts(m, " ");
|
||||
|
||||
seq_puts(m, "}");
|
||||
}
|
||||
|
||||
static void hist_trigger_entry_print(struct seq_file *m,
|
||||
struct hist_trigger_data *hist_data,
|
||||
void *key,
|
||||
struct tracing_map_elt *elt)
|
||||
{
|
||||
const char *field_name;
|
||||
unsigned int i;
|
||||
|
||||
hist_trigger_print_key(m, hist_data, key, elt);
|
||||
|
||||
seq_printf(m, " hitcount: %10llu",
|
||||
tracing_map_read_sum(elt, HITCOUNT_IDX));
|
||||
|
|
@ -5091,6 +5335,8 @@ static void hist_trigger_show(struct seq_file *m,
|
|||
if (n_entries < 0)
|
||||
n_entries = 0;
|
||||
|
||||
track_data_snapshot_print(m, hist_data);
|
||||
|
||||
seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n",
|
||||
(u64)atomic64_read(&hist_data->map->hits),
|
||||
n_entries, (u64)atomic64_read(&hist_data->map->drops));
|
||||
|
|
|
|||
Loading…
Reference in New Issue