From: "Steven Rostedt (Google)" <rostedt@xxxxxxxxxxx>
As the saved_cmdlines may miss a lot of comms, especially if the tracing
went for a while, to know what the comms mapping of PIDs are, use the
sched_switch event if it is present. If so, then update the task with the
comm and print that. This way we get more real names instead of just
"<...>".
Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
---
tracecmd/trace-analyze.c | 62 ++++++++++++++++++++++++++++++++++++++--
1 file changed, 60 insertions(+), 2 deletions(-)
diff --git a/tracecmd/trace-analyze.c b/tracecmd/trace-analyze.c
index 43e9ffa95687..dec705ce8e15 100644
--- a/tracecmd/trace-analyze.c
+++ b/tracecmd/trace-analyze.c
@@ -29,6 +29,10 @@ struct cpu_data {
struct analysis_data {
unsigned long long start_ts;
unsigned long long last_ts;
+ struct tep_event *switch_event;
+ struct tep_format_field *prev_comm;
+ struct tep_format_field *next_comm;
+ struct tep_format_field *next_pid;
struct cpu_data *cpu_data;
struct trace_hash tasks;
int nr_tasks;
@@ -39,6 +43,7 @@ struct analysis_data {
struct task_item {
unsigned long long runtime;
unsigned long long start_ts;
+ char *comm;
struct trace_hash_item hash;
int pid;
};
@@ -253,11 +258,51 @@ static void update_first_pid(struct cpu_data *cpu_data)
cpu_data->start_ts = start_ts;
}
+static void process_switch(struct analysis_data *data,
+ struct tep_handle *tep, int pid,
+ struct tep_record *record)
+{
+ struct cpu_data *cpu_data = &data->cpu_data[record->cpu];
+ struct task_cpu_item *cpu_task;
+ struct task_item *task;
+ const char *comm;
+
+ cpu_task = get_cpu_task(cpu_data, pid);
+ task = cpu_task->task;
+
+ /* Fill in missing comms */
+ if (pid && data->prev_comm && !task->comm) {
+ comm = (char *)(record->data + data->prev_comm->offset);
+ task->comm = strdup(comm);
+ }
+
+ if (data->next_pid) {
+ unsigned long long val;
+
+ tep_read_number_field(data->next_pid, record->data, &val);
+ pid = val;
+ cpu_task = get_cpu_task(cpu_data, pid);
+ task = cpu_task->task;
+
+ /* Fill in missing comms */
+ if (pid && data->next_comm && !task->comm) {
+ comm = (char *)(record->data + data->next_comm->offset);
+ task->comm = strdup(comm);
+ }
+ }
+}
+
+static bool match_type(int type, struct tep_event *event)
+{
+ return event && type == event->id;
+}
+
static void process_cpu(struct analysis_data *data,
struct tep_handle *tep,
struct tep_record *record)
{
struct cpu_data *cpu_data;
+ int type;
int pid;
pid = tep_data_pid(tep, record);
@@ -266,6 +311,10 @@ static void process_cpu(struct analysis_data *data,
cpu_data = get_cpu_data(data, record);
update_cpu_times(cpu_data, tep, pid, record);
+
+ type = tep_data_type(tep, record);
+ if (match_type(type, data->switch_event))
+ process_switch(data, tep, pid, record);
}
static int cmp_tasks(const void *A, const void *B)
@@ -374,7 +423,7 @@ static void print_cpu_data(struct tep_handle *tep, struct cpu_data *cpu_data)
printf(" --------- --- \t --------\n");
}
printf("%16s %8d\t",
- tep_data_comm_from_pid(tep, task->pid),
+ task->comm ? : tep_data_comm_from_pid(tep, task->pid),
task->pid);
print_time(cpu_tasks[i]->runtime, '_');
printf(" (%%%lld)\n", (task->runtime * 100) / total_time);
@@ -444,7 +493,7 @@ static void print_total(struct tep_handle *tep, struct analysis_data *data)
printf(" --------- --- \t --------\n");
}
printf("%16s %8d\t",
- tep_data_comm_from_pid(tep, tasks[i]->pid),
+ tasks[i]->comm ? : tep_data_comm_from_pid(tep, tasks[i]->pid),
tasks[i]->pid);
print_time(tasks[i]->runtime, '_');
printf(" (%%%lld)\n", (tasks[i]->runtime * 100) / total_time);
@@ -470,6 +519,7 @@ static void free_tasks(struct trace_hash *hash)
trace_hash_while_item(item, bucket) {
task = task_from_hash(item);
trace_hash_del(item);
+ free(task->comm);
free(task);
}
}
@@ -518,9 +568,17 @@ static void do_trace_analyze(struct tracecmd_input *handle)
trace_hash_init(&data.tasks, 128);
+ data.switch_event = tep_find_event_by_name(tep, "sched", "sched_switch");
+
/* Set to a very large number */
data.start_ts = -1ULL;
+ if (data.switch_event) {
+ data.next_pid = tep_find_field(data.switch_event, "next_pid");
+ data.next_comm = tep_find_field(data.switch_event, "next_comm");
+ data.prev_comm = tep_find_field(data.switch_event, "prev_comm");
+ }
+
do {
record = tracecmd_read_next_data(handle, NULL);
if (record)
--
2.35.1
