linux_old1/tools/perf/util/thread_map.c

170 lines
3.3 KiB
C

#include <dirent.h>
#include <limits.h>
#include <stdbool.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include "thread_map.h"
/* Skip "." and ".." directories */
static int filter(const struct dirent *dir)
{
if (dir->d_name[0] == '.')
return 0;
else
return 1;
}
struct thread_map *thread_map__new_by_pid(pid_t pid)
{
struct thread_map *threads;
char name[256];
int items;
struct dirent **namelist = NULL;
int i;
sprintf(name, "/proc/%d/task", pid);
items = scandir(name, &namelist, filter, NULL);
if (items <= 0)
return NULL;
threads = malloc(sizeof(*threads) + sizeof(pid_t) * items);
if (threads != NULL) {
for (i = 0; i < items; i++)
threads->map[i] = atoi(namelist[i]->d_name);
threads->nr = items;
}
for (i=0; i<items; i++)
free(namelist[i]);
free(namelist);
return threads;
}
struct thread_map *thread_map__new_by_tid(pid_t tid)
{
struct thread_map *threads = malloc(sizeof(*threads) + sizeof(pid_t));
if (threads != NULL) {
threads->map[0] = tid;
threads->nr = 1;
}
return threads;
}
struct thread_map *thread_map__new_by_uid(uid_t uid)
{
DIR *proc;
int max_threads = 32, items, i;
char path[256];
struct dirent dirent, *next, **namelist = NULL;
struct thread_map *threads = malloc(sizeof(*threads) +
max_threads * sizeof(pid_t));
if (threads == NULL)
goto out;
proc = opendir("/proc");
if (proc == NULL)
goto out_free_threads;
threads->nr = 0;
while (!readdir_r(proc, &dirent, &next) && next) {
char *end;
bool grow = false;
struct stat st;
pid_t pid = strtol(dirent.d_name, &end, 10);
if (*end) /* only interested in proper numerical dirents */
continue;
snprintf(path, sizeof(path), "/proc/%s", dirent.d_name);
if (stat(path, &st) != 0)
continue;
if (st.st_uid != uid)
continue;
snprintf(path, sizeof(path), "/proc/%d/task", pid);
items = scandir(path, &namelist, filter, NULL);
if (items <= 0)
goto out_free_closedir;
while (threads->nr + items >= max_threads) {
max_threads *= 2;
grow = true;
}
if (grow) {
struct thread_map *tmp;
tmp = realloc(threads, (sizeof(*threads) +
max_threads * sizeof(pid_t)));
if (tmp == NULL)
goto out_free_namelist;
threads = tmp;
}
for (i = 0; i < items; i++)
threads->map[threads->nr + i] = atoi(namelist[i]->d_name);
for (i = 0; i < items; i++)
free(namelist[i]);
free(namelist);
threads->nr += items;
}
out_closedir:
closedir(proc);
out:
return threads;
out_free_threads:
free(threads);
return NULL;
out_free_namelist:
for (i = 0; i < items; i++)
free(namelist[i]);
free(namelist);
out_free_closedir:
free(threads);
threads = NULL;
goto out_closedir;
}
struct thread_map *thread_map__new(pid_t pid, pid_t tid, uid_t uid)
{
if (pid != -1)
return thread_map__new_by_pid(pid);
if (tid == -1 && uid != UINT_MAX)
return thread_map__new_by_uid(uid);
return thread_map__new_by_tid(tid);
}
void thread_map__delete(struct thread_map *threads)
{
free(threads);
}
size_t thread_map__fprintf(struct thread_map *threads, FILE *fp)
{
int i;
size_t printed = fprintf(fp, "%d thread%s: ",
threads->nr, threads->nr > 1 ? "s" : "");
for (i = 0; i < threads->nr; ++i)
printed += fprintf(fp, "%s%d", i ? ", " : "", threads->map[i]);
return printed + fprintf(fp, "\n");
}