Use mmap to create the pthread_internal_t

[android-sdk/platform-bionic.git] / libc / bionic / pthread_internals.cpp

diff --git a/libc/bionic/pthread_internals.cpp b/libc/bionic/pthread_internals.cpp
index 19c00d47c5b7b5ba15d7a56ee0a1314c18de9c38..7c30e6e4ad413e667bf7382e66823d4f9f33d850 100644 (file)
--- a/libc/bionic/pthread_internals.cpp
+++ b/libc/bionic/pthread_internals.cpp
@@ -28,14 +28,20 @@
 
 #include "pthread_internal.h"
 
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+
 #include "private/bionic_futex.h"
 #include "private/bionic_tls.h"
+#include "private/libc_logging.h"
 #include "private/ScopedPthreadMutexLocker.h"
 
 pthread_internal_t* g_thread_list = NULL;
 pthread_mutex_t g_thread_list_lock = PTHREAD_MUTEX_INITIALIZER;
 
-void _pthread_internal_remove_locked(pthread_internal_t* thread) {
+void _pthread_internal_remove_locked(pthread_internal_t* thread, bool free_thread) {
   if (thread->next != NULL) {
     thread->next->prev = thread->prev;
   }
@@ -45,10 +51,11 @@ void _pthread_internal_remove_locked(pthread_internal_t* thread) {
     g_thread_list = thread->next;
   }
 
-  // The main thread is not heap-allocated. See __libc_init_tls for the declaration,
-  // and __libc_init_common for the point where it's added to the thread list.
-  if ((thread->attr.flags & PTHREAD_ATTR_FLAG_MAIN_THREAD) == 0) {
-    free(thread);
+  // For threads using user allocated stack (including the main thread), the pthread_internal_t
+  // can't be freed since it is on the stack.
+  if (free_thread && !(thread->attr.flags & PTHREAD_ATTR_FLAG_USER_ALLOCATED_STACK)) {
+    // Use one munmap to free the whole thread stack, including pthread_internal_t.
+    munmap(thread->attr.stack_base, thread->attr.stack_size);
   }
 }