optimize POSIX TSD for fast pthread_getspecific

diff --git a/src/thread/pthread_getspecific.c b/src/thread/pthread_getspecific.c
index a6ca27d..b2a282c 100644 (file)
--- 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 efc3804..52c0973 100644 (file)
--- 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 3a4d4c5..028d387 100644 (file)
--- 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 171cef4..55e46a8 100644 (file)
--- 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;