From b480808a6a511c9350a6559b63938ac261c83a76 Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Thu, 3 Mar 2011 18:30:44 -0500 Subject: [PATCH] optimize POSIX TSD for fast pthread_getspecific --- src/thread/pthread_getspecific.c | 3 +-- src/thread/pthread_key_create.c | 1 + src/thread/pthread_self.c | 11 +++++++++++ src/thread/pthread_setspecific.c | 8 +------- 4 files changed, 14 insertions(+), 9 deletions(-) diff --git a/src/thread/pthread_getspecific.c b/src/thread/pthread_getspecific.c index a6ca27d0..b2a282c6 100644 --- a/src/thread/pthread_getspecific.c +++ b/src/thread/pthread_getspecific.c @@ -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]; } diff --git a/src/thread/pthread_key_create.c b/src/thread/pthread_key_create.c index efc38046..52c09734 100644 --- a/src/thread/pthread_key_create.c +++ b/src/thread/pthread_key_create.c @@ -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 */ diff --git a/src/thread/pthread_self.c b/src/thread/pthread_self.c index 3a4d4c58..028d387b 100644 --- a/src/thread/pthread_self.c +++ b/src/thread/pthread_self.c @@ -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; diff --git a/src/thread/pthread_setspecific.c b/src/thread/pthread_setspecific.c index 171cef41..55e46a89 100644 --- a/src/thread/pthread_setspecific.c +++ b/src/thread/pthread_setspecific.c @@ -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; -- 2.25.1