linux/tools/perf/util/thread.c
Adrian Hunter a848080836 perf tools: Only override the default :tid comm entry
Events may still be ordered even if there are no timestamps e.g. if the
data is recorded per-thread.

Also synthesized COMM events have a timestamp of zero.

Consequently it is better to keep comm entries even if they have a
timestamp of zero.

However, when a struct thread is created the command string is not known
and a comm entry with a string of the form ":<tid>" is used.

In that case thread->comm_set is false and the comm entry should be
overridden.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1415715423-15563-4-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-11-19 12:37:26 -03:00

220 lines
4.4 KiB
C

#include "../perf.h"
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "session.h"
#include "thread.h"
#include "thread-stack.h"
#include "util.h"
#include "debug.h"
#include "comm.h"
#include "unwind.h"
int thread__init_map_groups(struct thread *thread, struct machine *machine)
{
struct thread *leader;
pid_t pid = thread->pid_;
if (pid == thread->tid || pid == -1) {
thread->mg = map_groups__new(machine);
} else {
leader = machine__findnew_thread(machine, pid, pid);
if (leader)
thread->mg = map_groups__get(leader->mg);
}
return thread->mg ? 0 : -1;
}
struct thread *thread__new(pid_t pid, pid_t tid)
{
char *comm_str;
struct comm *comm;
struct thread *thread = zalloc(sizeof(*thread));
if (thread != NULL) {
thread->pid_ = pid;
thread->tid = tid;
thread->ppid = -1;
thread->cpu = -1;
INIT_LIST_HEAD(&thread->comm_list);
if (unwind__prepare_access(thread) < 0)
goto err_thread;
comm_str = malloc(32);
if (!comm_str)
goto err_thread;
snprintf(comm_str, 32, ":%d", tid);
comm = comm__new(comm_str, 0, false);
free(comm_str);
if (!comm)
goto err_thread;
list_add(&comm->list, &thread->comm_list);
}
return thread;
err_thread:
free(thread);
return NULL;
}
void thread__delete(struct thread *thread)
{
struct comm *comm, *tmp;
thread_stack__free(thread);
if (thread->mg) {
map_groups__put(thread->mg);
thread->mg = NULL;
}
list_for_each_entry_safe(comm, tmp, &thread->comm_list, list) {
list_del(&comm->list);
comm__free(comm);
}
unwind__finish_access(thread);
free(thread);
}
struct comm *thread__comm(const struct thread *thread)
{
if (list_empty(&thread->comm_list))
return NULL;
return list_first_entry(&thread->comm_list, struct comm, list);
}
struct comm *thread__exec_comm(const struct thread *thread)
{
struct comm *comm, *last = NULL;
list_for_each_entry(comm, &thread->comm_list, list) {
if (comm->exec)
return comm;
last = comm;
}
return last;
}
int __thread__set_comm(struct thread *thread, const char *str, u64 timestamp,
bool exec)
{
struct comm *new, *curr = thread__comm(thread);
int err;
/* Override the default :tid entry */
if (!thread->comm_set) {
err = comm__override(curr, str, timestamp, exec);
if (err)
return err;
} else {
new = comm__new(str, timestamp, exec);
if (!new)
return -ENOMEM;
list_add(&new->list, &thread->comm_list);
if (exec)
unwind__flush_access(thread);
}
thread->comm_set = true;
return 0;
}
const char *thread__comm_str(const struct thread *thread)
{
const struct comm *comm = thread__comm(thread);
if (!comm)
return NULL;
return comm__str(comm);
}
/* CHECKME: it should probably better return the max comm len from its comm list */
int thread__comm_len(struct thread *thread)
{
if (!thread->comm_len) {
const char *comm = thread__comm_str(thread);
if (!comm)
return 0;
thread->comm_len = strlen(comm);
}
return thread->comm_len;
}
size_t thread__fprintf(struct thread *thread, FILE *fp)
{
return fprintf(fp, "Thread %d %s\n", thread->tid, thread__comm_str(thread)) +
map_groups__fprintf(thread->mg, fp);
}
void thread__insert_map(struct thread *thread, struct map *map)
{
map_groups__fixup_overlappings(thread->mg, map, stderr);
map_groups__insert(thread->mg, map);
}
static int thread__clone_map_groups(struct thread *thread,
struct thread *parent)
{
int i;
/* This is new thread, we share map groups for process. */
if (thread->pid_ == parent->pid_)
return 0;
/* But this one is new process, copy maps. */
for (i = 0; i < MAP__NR_TYPES; ++i)
if (map_groups__clone(thread->mg, parent->mg, i) < 0)
return -ENOMEM;
return 0;
}
int thread__fork(struct thread *thread, struct thread *parent, u64 timestamp)
{
int err;
if (parent->comm_set) {
const char *comm = thread__comm_str(parent);
if (!comm)
return -ENOMEM;
err = thread__set_comm(thread, comm, timestamp);
if (err)
return err;
thread->comm_set = true;
}
thread->ppid = parent->tid;
return thread__clone_map_groups(thread, parent);
}
void thread__find_cpumode_addr_location(struct thread *thread,
enum map_type type, u64 addr,
struct addr_location *al)
{
size_t i;
const u8 const cpumodes[] = {
PERF_RECORD_MISC_USER,
PERF_RECORD_MISC_KERNEL,
PERF_RECORD_MISC_GUEST_USER,
PERF_RECORD_MISC_GUEST_KERNEL
};
for (i = 0; i < ARRAY_SIZE(cpumodes); i++) {
thread__find_addr_location(thread, cpumodes[i], type, addr, al);
if (al->map)
break;
}
}