[PATCH 02/13] nptl: Remove futex_wait_cancelable

Adhemerval Zanella adhemerval.zanella@linaro.org
Mon Nov 23 19:52:45 GMT 2020


It is used solely on __pthread_cond_wait_common and the call can be
replaced by a __futex_abstimed_wait_cancelable64 one.

Checked on x86_64-linux-gnu and i686-linux-gnu.
---
 nptl/pthread_cond_wait.c      | 22 ++--------------------
 sysdeps/nptl/futex-internal.h | 29 -----------------------------
 2 files changed, 2 insertions(+), 49 deletions(-)

diff --git a/nptl/pthread_cond_wait.c b/nptl/pthread_cond_wait.c
index 7d158d553f..685dbca32f 100644
--- a/nptl/pthread_cond_wait.c
+++ b/nptl/pthread_cond_wait.c
@@ -501,26 +501,8 @@ __pthread_cond_wait_common (pthread_cond_t *cond, pthread_mutex_t *mutex,
 	  cbuffer.private = private;
 	  __pthread_cleanup_push (&buffer, __condvar_cleanup_waiting, &cbuffer);
 
-	  if (abstime == NULL)
-	    {
-	      /* Block without a timeout.  */
-	      err = futex_wait_cancelable (
-		  cond->__data.__g_signals + g, 0, private);
-	    }
-	  else
-	    {
-	      /* Block, but with a timeout.
-		 Work around the fact that the kernel rejects negative timeout
-		 values despite them being valid.  */
-	      if (__glibc_unlikely (abstime->tv_sec < 0))
-	        err = ETIMEDOUT;
-	      else
-		{
-		  err = __futex_abstimed_wait_cancelable64
-                    (cond->__data.__g_signals + g, 0, clockid, abstime,
-                     private);
-		}
-	    }
+	  err = __futex_abstimed_wait_cancelable64 (
+	    cond->__data.__g_signals + g, 0, clockid, abstime, private);
 
 	  __pthread_cleanup_pop (&buffer, 0);
 
diff --git a/sysdeps/nptl/futex-internal.h b/sysdeps/nptl/futex-internal.h
index 21e3b74be6..96d1318091 100644
--- a/sysdeps/nptl/futex-internal.h
+++ b/sysdeps/nptl/futex-internal.h
@@ -177,35 +177,6 @@ futex_wait_simple (unsigned int *futex_word, unsigned int expected,
   ignore_value (futex_wait (futex_word, expected, private));
 }
 
-
-/* Like futex_wait but is a POSIX cancellation point.  */
-static __always_inline int
-futex_wait_cancelable (unsigned int *futex_word, unsigned int expected,
-		       int private)
-{
-  int oldtype;
-  oldtype = __pthread_enable_asynccancel ();
-  int err = lll_futex_timed_wait (futex_word, expected, NULL, private);
-  __pthread_disable_asynccancel (oldtype);
-  switch (err)
-    {
-    case 0:
-    case -EAGAIN:
-    case -EINTR:
-      return -err;
-
-    case -ETIMEDOUT: /* Cannot have happened as we provided no timeout.  */
-    case -EFAULT: /* Must have been caused by a glibc or application bug.  */
-    case -EINVAL: /* Either due to wrong alignment or due to the timeout not
-		     being normalized.  Must have been caused by a glibc or
-		     application bug.  */
-    case -ENOSYS: /* Must have been caused by a glibc bug.  */
-    /* No other errors are documented at this time.  */
-    default:
-      futex_fatal_error ();
-    }
-}
-
 /* Like futex_wait, but will eventually time out (i.e., stop being
    blocked) after the duration of time provided (i.e., RELTIME) has
    passed.  The caller must provide a normalized RELTIME.  RELTIME can also
-- 
2.25.1



More information about the Libc-alpha mailing list