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 09c48dcd37224a76a9e13da10afef69232ff7de3..7c30e6e4ad413e667bf7382e66823d4f9f33d850 100644 (file)
--- a/libc/bionic/pthread_internals.cpp
+++ b/libc/bionic/pthread_internals.cpp
@@ -28,71 +28,49 @@
 
 #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_pthread.h"
 #include "private/bionic_tls.h"
+#include "private/libc_logging.h"
 #include "private/ScopedPthreadMutexLocker.h"
 
-pthread_internal_t* gThreadList = NULL;
-pthread_mutex_t gThreadListLock = PTHREAD_MUTEX_INITIALIZER;
+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;
   }
   if (thread->prev != NULL) {
     thread->prev->next = thread->next;
   } else {
-    gThreadList = thread->next;
+    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);
   }
 }
 
 void _pthread_internal_add(pthread_internal_t* thread) {
-  ScopedPthreadMutexLocker locker(&gThreadListLock);
+  ScopedPthreadMutexLocker locker(&g_thread_list_lock);
 
   // We insert at the head.
-  thread->next = gThreadList;
+  thread->next = g_thread_list;
   thread->prev = NULL;
   if (thread->next != NULL) {
     thread->next->prev = thread;
   }
-  gThreadList = thread;
+  g_thread_list = thread;
 }
 
 pthread_internal_t* __get_thread(void) {
   return reinterpret_cast<pthread_internal_t*>(__get_tls()[TLS_SLOT_THREAD_ID]);
 }
-
-pid_t __pthread_gettid(pthread_t t) {
-  return reinterpret_cast<pthread_internal_t*>(t)->tid;
-}
-
-// Initialize 'ts' with the difference between 'abstime' and the current time
-// according to 'clock'. Returns -1 if abstime already expired, or 0 otherwise.
-int __timespec_to_absolute(timespec* ts, const timespec* abstime, clockid_t clock) {
-  clock_gettime(clock, ts);
-  ts->tv_sec  = abstime->tv_sec - ts->tv_sec;
-  ts->tv_nsec = abstime->tv_nsec - ts->tv_nsec;
-  if (ts->tv_nsec < 0) {
-    ts->tv_sec--;
-    ts->tv_nsec += 1000000000;
-  }
-  if ((ts->tv_nsec < 0) || (ts->tv_sec < 0)) {
-    return -1;
-  }
-  return 0;
-}
-
-int __futex_wake_ex(volatile void* ftx, int pshared, int val) {
-  return __futex_syscall3(ftx, pshared ? FUTEX_WAKE : FUTEX_WAKE_PRIVATE, val);
-}
-
-int __futex_wait_ex(volatile void* ftx, int pshared, int val, const timespec* timeout) {
-  return __futex_syscall4(ftx, pshared ? FUTEX_WAIT : FUTEX_WAIT_PRIVATE, val, timeout);
-}