1 files changed, 58 insertions, 54 deletions

diff --git a/nptl/cancellation.c b/nptl/cancellation.c
index 765511d66d..eee5b6b758 100644
--- a/nptl/cancellation.c
+++ b/nptl/cancellation.c
@@ -18,74 +18,78 @@
 #include <setjmp.h>
 #include <stdlib.h>
 #include "pthreadP.h"
-#include <futex-internal.h>
 
-
-/* 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.  These functions must be
-   AS-safe, with the exception of the actual cancellation, because they
-   are called by wrappers around AS-safe functions like write().*/
-int
-__pthread_enable_asynccancel (void)
+/* Called by the INTERNAL_SYSCALL_CANCEL macro, check for cancellation and
+   returns the syscall value or its negative error code.  */
+long int
+__internal_syscall_cancel (__syscall_arg_t a1, __syscall_arg_t a2,
+			   __syscall_arg_t a3, __syscall_arg_t a4,
+			   __syscall_arg_t a5, __syscall_arg_t a6,
+			   __syscall_arg_t nr)
 {
-  struct pthread *self = THREAD_SELF;
-  int oldval = atomic_load_relaxed (&self->cancelhandling);
+  long int result;
+  struct pthread *pd = THREAD_SELF;
 
-  while (1)
+  /* If cancellation is not enabled, call the syscall directly and also
+     for thread terminatation to avoid call __syscall_do_cancel while
+     executing cleanup handlers.  */
+  int ch = atomic_load_relaxed (&pd->cancelhandling);
+  if (SINGLE_THREAD_P || !cancel_enabled (ch) || cancel_exiting (ch))
     {
-      int newval = oldval | CANCELTYPE_BITMASK;
-
-      if (newval == oldval)
-	break;
+      result = INTERNAL_SYSCALL_NCS_CALL (nr, a1, a2, a3, a4, a5, a6);
+      if (INTERNAL_SYSCALL_ERROR_P (result))
+	return -INTERNAL_SYSCALL_ERRNO (result);
+      return result;
+    }
 
-      if (atomic_compare_exchange_weak_acquire (&self->cancelhandling,
-						&oldval, newval))
-	{
-	  if (cancel_enabled_and_canceled_and_async (newval))
-	    {
-	      self->result = PTHREAD_CANCELED;
-	      __do_cancel ();
-	    }
+  /* Call the arch-specific entry points that contains the globals markers
+     to be checked by SIGCANCEL handler.  */
+  result = __syscall_cancel_arch (&pd->cancelhandling, nr, a1, a2, a3, a4, a5,
+			          a6);
 
-	  break;
-	}
-    }
+  /* If the cancellable syscall was interrupted by SIGCANCEL and it has not
+     side-effect, cancel the thread if cancellation is enabled.  */
+  ch = atomic_load_relaxed (&pd->cancelhandling);
+  if (result == -EINTR && cancel_enabled_and_canceled (ch))
+    __syscall_do_cancel ();
 
-  return oldval;
+  return result;
 }
-libc_hidden_def (__pthread_enable_asynccancel)
 
-/* See the comment for __pthread_enable_asynccancel regarding
-   the AS-safety of this function.  */
-void
-__pthread_disable_asynccancel (int oldtype)
+/* Called by the SYSCALL_CANCEL macro, check for cancellation and return the
+   syscall expected success value (usually 0) or, in case of failure, -1 and
+   sets errno to syscall return value.  */
+long int
+__syscall_cancel (__syscall_arg_t a1, __syscall_arg_t a2,
+		  __syscall_arg_t a3, __syscall_arg_t a4,
+		  __syscall_arg_t a5, __syscall_arg_t a6,
+		  __syscall_arg_t nr)
 {
-  /* If asynchronous cancellation was enabled before we do not have
-     anything to do.  */
-  if (oldtype & CANCELTYPE_BITMASK)
-    return;
+  int r = __internal_syscall_cancel (a1, a2, a3, a4, a5, a6, nr);
+  return __glibc_unlikely (INTERNAL_SYSCALL_ERROR_P (r))
+	 ? SYSCALL_ERROR_LABEL (INTERNAL_SYSCALL_ERRNO (r))
+	 : r;
+}
 
+/* Called by __syscall_cancel_arch or function above start the thread
+   cancellation.  */
+_Noreturn void
+__syscall_do_cancel (void)
+{
   struct pthread *self = THREAD_SELF;
-  int newval;
+
+  /* Disable thread cancellation to avoid cancellable entrypoints to call
+     __syscall_do_cancel recursively.  */
   int oldval = atomic_load_relaxed (&self->cancelhandling);
-  do
+  while (1)
     {
-      newval = oldval & ~CANCELTYPE_BITMASK;
+      int newval = oldval | CANCELSTATE_BITMASK;
+      if (oldval == newval)
+	break;
+      if (atomic_compare_exchange_weak_acquire (&self->cancelhandling,
+						&oldval, newval))
+	break;
     }
-  while (!atomic_compare_exchange_weak_acquire (&self->cancelhandling,
-						&oldval, newval));
 
-  /* 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 (__glibc_unlikely ((newval & (CANCELING_BITMASK | CANCELED_BITMASK))
-			   == CANCELING_BITMASK))
-    {
-      futex_wait_simple ((unsigned int *) &self->cancelhandling, newval,
-			 FUTEX_PRIVATE);
-      newval = atomic_load_relaxed (&self->cancelhandling);
-    }
+  __do_cancel (PTHREAD_CANCELED);
 }
-libc_hidden_def (__pthread_disable_asynccancel)