optimize POSIX TSD for fast pthread_getspecific

This commit is contained in:
Rich Felker 2011-03-03 18:30:44 -05:00
parent a53d2f3425
commit b480808a6a
4 changed files with 14 additions and 9 deletions

View File

@ -2,7 +2,6 @@
void *pthread_getspecific(pthread_key_t k)
{
struct pthread *self = pthread_self();
if (!self->tsd) return 0;
struct pthread *self = __pthread_self();
return self->tsd[k];
}

View File

@ -12,6 +12,7 @@ int pthread_key_create(pthread_key_t *k, void (*dtor)(void *))
int i = (uintptr_t)&k / 16 % PTHREAD_KEYS_MAX;
int j = i;
pthread_self();
libc.tsd_keys = keys;
if (!dtor) dtor = nodtor;
/* Cheap trick - &k cannot match any destructor pointer */

View File

@ -2,6 +2,10 @@
static struct pthread main_thread;
/* pthread_key_create.c overrides this */
static const size_t dummy = 0;
weak_alias(dummy, __pthread_tsd_size);
#undef errno
static int *errno_location()
{
@ -10,6 +14,13 @@ static int *errno_location()
static int init_main_thread()
{
void *tsd = 0;
if (__pthread_tsd_size) {
tsd = mmap(0, __pthread_tsd_size, PROT_READ|PROT_WRITE,
MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
if (tsd == MAP_FAILED) return -1;
}
main_thread.tsd = tsd;
main_thread.self = &main_thread;
if (__set_thread_area(&main_thread) < 0)
return -1;

View File

@ -2,13 +2,7 @@
int pthread_setspecific(pthread_key_t k, const void *x)
{
struct pthread *self = pthread_self();
/* Handle the case of the main thread */
if (!self->tsd) {
if (!x) return 0;
if (!(self->tsd = calloc(sizeof(void *), PTHREAD_KEYS_MAX)))
return ENOMEM;
}
struct pthread *self = __pthread_self();
/* Avoid unnecessary COW */
if (self->tsd[k] != x) {
self->tsd[k] = (void *)x;