Unify source for async cancel handling.

Unify all three places where we enable async cancellation for
syscalls.  Optimize a bit.

4 files changed, 12 insertions, 189 deletions

diff --git a/nptl/ChangeLog b/nptl/ChangeLog
index b83128e..2308361 100644
--- a/nptl/ChangeLog
+++ b/nptl/ChangeLog
@@ -1,5 +1,10 @@
 2009-05-16  Ulrich Drepper  <drepper@redhat.com>
 
+	* cancellation.c (__pthread_disable_asynccancel): Remove unnecessary
+	test.
+	* libc-cancellation.c: Use <nptl/cancellation.c: to define the code.
+	* sysdeps/pthread/librt-cancellation.c: Likewise.
+
 	[BZ #9924]
 	* nptl-init.c: Renamed from init.c.
 	* Makefile: Change all occurences of init.c to nptl-init.c.
diff --git a/nptl/cancellation.c b/nptl/cancellation.c
index 2a6f83d..eac7973 100644
--- a/nptl/cancellation.c
+++ b/nptl/cancellation.c
@@ -78,9 +78,6 @@ __pthread_disable_asynccancel (int oldtype)
     {
       newval = oldval & ~CANCELTYPE_BITMASK;
 
-      if (newval == oldval)
-	break;
-
       int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling, newval,
 					      oldval);
       if (__builtin_expect (curval == oldval, 1))
diff --git a/nptl/libc-cancellation.c b/nptl/libc-cancellation.c
index cada464..432e1f8 100644
--- a/nptl/libc-cancellation.c
+++ b/nptl/libc-cancellation.c
@@ -17,106 +17,12 @@
    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
    02111-1307 USA.  */
 
-#include <setjmp.h>
-#include <stdlib.h>
 #include "pthreadP.h"
-#include <atomic.h>
-#include <bits/libc-lock.h>
 
 
-#ifndef NOT_IN_libc
-
-/* The next two functions are similar to pthread_setcanceltype() but
-   more specialized for the use in the cancelable functions like write().
-   They do not need to check parameters etc.  */
-int
-attribute_hidden
-__libc_enable_asynccancel (void)
-{
-  struct pthread *self = THREAD_SELF;
-  int oldval = THREAD_GETMEM (self, cancelhandling);
-
-  while (1)
-    {
-      int newval = oldval | CANCELTYPE_BITMASK;
-
-      if (__builtin_expect ((oldval & CANCELED_BITMASK) != 0, 0))
-	{
-	  /* If we are already exiting or if PTHREAD_CANCEL_DISABLED,
-	     stop right here.  */
-	  if ((oldval & (EXITING_BITMASK | CANCELSTATE_BITMASK)) != 0)
-	    break;
-
-	  int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling,
-						  newval, oldval);
-	  if (__builtin_expect (curval != oldval, 0))
-	    {
-	      /* Somebody else modified the word, try again.  */
-	      oldval = curval;
-	      continue;
-	    }
-
-	  THREAD_SETMEM (self, result, PTHREAD_CANCELED);
-
-	  __do_cancel ();
-
-	  /* NOTREACHED */
-	}
-
-      int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling, newval,
-					      oldval);
-      if (__builtin_expect (curval == oldval, 1))
-	break;
-
-      /* Prepare the next round.  */
-      oldval = curval;
-    }
-
-  return oldval;
-}
-
-
-void
-internal_function attribute_hidden
-__libc_disable_asynccancel (int oldtype)
-{
-  /* If asynchronous cancellation was enabled before we do not have
-     anything to do.  */
-  if (oldtype & CANCELTYPE_BITMASK)
-    return;
-
-  struct pthread *self = THREAD_SELF;
-  int newval;
-
-  int oldval = THREAD_GETMEM (self, cancelhandling);
-
-  while (1)
-    {
-      newval = oldval & ~CANCELTYPE_BITMASK;
-
-      if (newval == oldval)
-	break;
-
-      int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling, newval,
-					      oldval);
-      if (__builtin_expect (curval == oldval, 1))
-	break;
-
-      /* Prepare the next round.  */
-      oldval = curval;
-    }
-
-  /* We cannot return when we are being canceled.  Upon return the
-     thread might be things which would have to be undone.  The
-     following loop should loop until the cancellation signal is
-     delivered.  */
-  while (__builtin_expect ((newval & (CANCELING_BITMASK | CANCELED_BITMASK))
-			   == CANCELING_BITMASK, 0))
-    {
-      lll_futex_wait (&self->cancelhandling, newval, LLL_PRIVATE);
-      newval = THREAD_GETMEM (self, cancelhandling);
-    }
-}
+#define __pthread_enable_asynccancel __libc_enable_asynccancel
+#define __pthread_disable_asynccancel __libc_disable_asynccancel
+#include <nptl/cancellation.c>
 
 
 void
@@ -125,5 +31,3 @@ __libc_cleanup_routine (struct __pthread_cleanup_frame *f)
   if (f->__do_it)
     f->__cancel_routine (f->__cancel_arg);
 }
-
-#endif
diff --git a/nptl/sysdeps/pthread/librt-cancellation.c b/nptl/sysdeps/pthread/librt-cancellation.c
index 753a2d8..d9f7ad9 100644
--- a/nptl/sysdeps/pthread/librt-cancellation.c
+++ b/nptl/sysdeps/pthread/librt-cancellation.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
+/* Copyright (C) 2002, 2003, 2009 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
 
@@ -17,92 +17,9 @@
    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
    02111-1307 USA.  */
 
-#include <setjmp.h>
-#include <signal.h>
-#include <stdlib.h>
 #include "pthreadP.h"
-#include "atomic.h"
 
 
-#ifdef IS_IN_librt
-/* The next two functions are similar to pthread_setcanceltype() but
-   more specialized for the use in the cancelable functions like write().
-   They do not need to check parameters etc.  */
-int
-attribute_hidden
-__librt_enable_asynccancel (void)
-{
-  struct pthread *self = THREAD_SELF;
-  int oldval = THREAD_GETMEM (self, cancelhandling);
-
-  while (1)
-    {
-      int newval = oldval | CANCELTYPE_BITMASK;
-
-      if (__builtin_expect ((oldval & CANCELED_BITMASK) != 0, 0))
-	{
-	  /* If we are already exiting or if PTHREAD_CANCEL_DISABLED,
-	     stop right here.  */
-	  if ((oldval & (EXITING_BITMASK | CANCELSTATE_BITMASK)) != 0)
-	    break;
-
-	  int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling,
-						  newval, oldval);
-	  if (__builtin_expect (curval != oldval, 0))
-	    {
-	      /* Somebody else modified the word, try again.  */
-	      oldval = curval;
-	      continue;
-	    }
-
-	  THREAD_SETMEM (self, result, PTHREAD_CANCELED);
-
-	  __do_cancel ();
-
-	  /* NOTREACHED */
-	}
-
-      int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling, newval,
-					      oldval);
-      if (__builtin_expect (curval == oldval, 1))
-	break;
-
-      /* Prepare the next round.  */
-      oldval = curval;
-    }
-
-  return oldval;
-}
-
-
-void
-internal_function attribute_hidden
-__librt_disable_asynccancel (int oldtype)
-{
-  /* If asynchronous cancellation was enabled before we do not have
-     anything to do.  */
-  if (oldtype & CANCELTYPE_BITMASK)
-    return;
-
-  struct pthread *self = THREAD_SELF;
-  int oldval = THREAD_GETMEM (self, cancelhandling);
-
-  while (1)
-    {
-      int newval = oldval & ~CANCELTYPE_BITMASK;
-
-      if (newval == oldval)
-	break;
-
-      int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling, newval,
-					      oldval);
-      if (__builtin_expect (curval == oldval, 1))
-	break;
-
-      /* Prepare the next round.  */
-      oldval = curval;
-    }
-}
-
-
-#endif
+#define __pthread_enable_asynccancel __librt_enable_asynccancel
+#define __pthread_disable_asynccancel __librt_disable_asynccancel
+#include <nptl/cancellation.c>