optimize POSIX TSD for fast pthread_getspecific

[musl] / src / thread / pthread_self.c

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;