Add per-thread cache to malloc

[thirdparty/glibc.git] / nptl / pthread_mutex_init.c

diff --git a/nptl/pthread_mutex_init.c b/nptl/pthread_mutex_init.c
index 174d900dc8cc20e42fd0b52c20677c1cda85553e..6f2fc808ff1b140af98b197bf241eb3ec8866b2a 100644 (file)
--- a/nptl/pthread_mutex_init.c
+++ b/nptl/pthread_mutex_init.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2002-2013 Free Software Foundation, Inc.
+/* Copyright (C) 2002-2017 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
 
@@ -18,9 +18,11 @@
 
 #include <assert.h>
 #include <errno.h>
+#include <stdbool.h>
 #include <string.h>
 #include <kernel-features.h>
 #include "pthreadP.h"
+#include <atomic.h>
 
 #include <stap-probe.h>
 
@@ -31,15 +33,27 @@ static const struct pthread_mutexattr default_mutexattr =
   };
 
 
-#ifndef __ASSUME_FUTEX_LOCK_PI
-static int tpi_supported;
+static bool
+prio_inherit_missing (void)
+{
+#ifdef __NR_futex
+  static int tpi_supported;
+  if (__glibc_unlikely (tpi_supported == 0))
+    {
+      int lock = 0;
+      INTERNAL_SYSCALL_DECL (err);
+      int ret = INTERNAL_SYSCALL (futex, err, 4, &lock, FUTEX_UNLOCK_PI, 0, 0);
+      assert (INTERNAL_SYSCALL_ERROR_P (ret, err));
+      tpi_supported = INTERNAL_SYSCALL_ERRNO (ret, err) == ENOSYS ? -1 : 1;
+    }
+  return __glibc_unlikely (tpi_supported < 0);
 #endif
-
+  return true;
+}
 
 int
-__pthread_mutex_init (mutex, mutexattr)
-     pthread_mutex_t *mutex;
-     const pthread_mutexattr_t *mutexattr;
+__pthread_mutex_init (pthread_mutex_t *mutex,
+                     const pthread_mutexattr_t *mutexattr)
 {
   const struct pthread_mutexattr *imutexattr;
 
@@ -58,19 +72,8 @@ __pthread_mutex_init (mutex, mutexattr)
       break;
 
     case PTHREAD_PRIO_INHERIT << PTHREAD_MUTEXATTR_PROTOCOL_SHIFT:
-#ifndef __ASSUME_FUTEX_LOCK_PI
-      if (__builtin_expect (tpi_supported == 0, 0))
-       {
-         int lock = 0;
-         INTERNAL_SYSCALL_DECL (err);
-         int ret = INTERNAL_SYSCALL (futex, err, 4, &lock, FUTEX_UNLOCK_PI,
-                                     0, 0);
-         assert (INTERNAL_SYSCALL_ERROR_P (ret, err));
-         tpi_supported = INTERNAL_SYSCALL_ERRNO (ret, err) == ENOSYS ? -1 : 1;
-       }
-      if (__builtin_expect (tpi_supported < 0, 0))
+      if (__glibc_unlikely (prio_inherit_missing ()))
        return ENOTSUP;
-#endif
       break;
 
     default:
@@ -111,10 +114,11 @@ __pthread_mutex_init (mutex, mutexattr)
                    >> PTHREAD_MUTEXATTR_PRIO_CEILING_SHIFT;
       if (! ceiling)
        {
-         if (__sched_fifo_min_prio == -1)
+         /* See __init_sched_fifo_prio.  */
+         if (atomic_load_relaxed (&__sched_fifo_min_prio) == -1)
            __init_sched_fifo_prio ();
-         if (ceiling < __sched_fifo_min_prio)
-           ceiling = __sched_fifo_min_prio;
+         if (ceiling < atomic_load_relaxed (&__sched_fifo_min_prio))
+           ceiling = atomic_load_relaxed (&__sched_fifo_min_prio);
        }
       mutex->__data.__lock = ceiling << PTHREAD_MUTEX_PRIO_CEILING_SHIFT;
       break;
@@ -140,5 +144,5 @@ __pthread_mutex_init (mutex, mutexattr)
 
   return 0;
 }
-strong_alias (__pthread_mutex_init, pthread_mutex_init)
+weak_alias (__pthread_mutex_init, pthread_mutex_init)
 hidden_def (__pthread_mutex_init)