nptl: Add clockid parameter to futex timed wait calls

In preparation for adding POSIX clockwait variants of timedwait functions,
add a clockid_t parameter to futex_abstimed_wait functions and pass
CLOCK_REALTIME from all callers for the time being.

Replace lll_futex_timed_wait_bitset with lll_futex_clock_wait_bitset
which takes a clockid_t parameter rather than the magic clockbit.

	* sysdeps/nptl/lowlevellock-futex.h,
	sysdeps/unix/sysv/linux/lowlevellock-futex.h: Replace
	lll_futex_timed_wait_bitset with lll_futex_clock_wait_bitset that
	takes a clockid rather than a special clockbit.
	* sysdeps/nptl/lowlevellock-futex.h: Add
	lll_futex_supported_clockid so that client functions can check
	whether their clockid parameter is valid even if they don't
	ultimately end up calling lll_futex_clock_wait_bitset.
	* sysdeps/nptl/futex-internal.h,
	sysdeps/unix/sysv/linux/futex-internal.h
	(futex_abstimed_wait, futex_abstimed_wait_cancelable): Add
	clockid_t parameter to indicate which clock the absolute time
	passed should be measured against. Pass that clockid onto
	lll_futex_clock_wait_bitset. Add invalid clock as reason for
	returning -EINVAL.
	* sysdeps/nptl/futex-internal.h,
	sysdeps/unix/sysv/linux/futex-internal.h: Introduce
	futex_abstimed_supported_clockid so that client functions can check
	whether their clockid parameter is valid even if they don't
	ultimately end up calling futex_abstimed_wait.
	* nptl/pthread_cond_wait.c (__pthread_cond_wait_common): Remove
	code to calculate relative timeout for
	__PTHREAD_COND_CLOCK_MONOTONIC_MASK and just pass CLOCK_MONOTONIC
	or CLOCK_REALTIME as required to futex_abstimed_wait_cancelable.
	* nptl/pthread_rwlock_common (__pthread_rwlock_rdlock_full)
	(__pthread_wrlock_full), nptl/sem_waitcommon (do_futex_wait): Pass
	additional CLOCK_REALTIME to futex_abstimed_wait_cancelable.
	* nptl/pthread_mutex_timedlock.c (__pthread_mutex_timedlock):
	Switch to lll_futex_clock_wait_bitset and pass CLOCK_REALTIME

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>

4 files changed, 16 insertions, 34 deletions

diff --git a/nptl/pthread_cond_wait.c b/nptl/pthread_cond_wait.c
index 9a0f29e..7385562 100644
--- a/nptl/pthread_cond_wait.c
+++ b/nptl/pthread_cond_wait.c
@@ -509,35 +509,15 @@ __pthread_cond_wait_common (pthread_cond_t *cond, pthread_mutex_t *mutex,
 		 values despite them being valid.  */
 	      if (__glibc_unlikely (abstime->tv_sec < 0))
 	        err = ETIMEDOUT;
-
-	      else if ((flags & __PTHREAD_COND_CLOCK_MONOTONIC_MASK) != 0)
-		{
-		  /* CLOCK_MONOTONIC is requested.  */
-		  struct timespec rt;
-		  if (__clock_gettime (CLOCK_MONOTONIC, &rt) != 0)
-		    __libc_fatal ("clock_gettime does not support "
-				  "CLOCK_MONOTONIC\n");
-		  /* Convert the absolute timeout value to a relative
-		     timeout.  */
-		  rt.tv_sec = abstime->tv_sec - rt.tv_sec;
-		  rt.tv_nsec = abstime->tv_nsec - rt.tv_nsec;
-		  if (rt.tv_nsec < 0)
-		    {
-		      rt.tv_nsec += 1000000000;
-		      --rt.tv_sec;
-		    }
-		  /* Did we already time out?  */
-		  if (__glibc_unlikely (rt.tv_sec < 0))
-		    err = ETIMEDOUT;
-		  else
-		    err = futex_reltimed_wait_cancelable
-			(cond->__data.__g_signals + g, 0, &rt, private);
-		}
 	      else
 		{
-		  /* Use CLOCK_REALTIME.  */
+		  const clockid_t clockid =
+		    ((flags & __PTHREAD_COND_CLOCK_MONOTONIC_MASK) != 0) ?
+		    CLOCK_MONOTONIC : CLOCK_REALTIME;
+
 		  err = futex_abstimed_wait_cancelable
-		      (cond->__data.__g_signals + g, 0, abstime, private);
+                    (cond->__data.__g_signals + g, 0, clockid, abstime,
+                     private);
 		}
 	    }
 
diff --git a/nptl/pthread_mutex_timedlock.c b/nptl/pthread_mutex_timedlock.c
index 270b072..d4d11cc 100644
--- a/nptl/pthread_mutex_timedlock.c
+++ b/nptl/pthread_mutex_timedlock.c
@@ -266,8 +266,8 @@ __pthread_mutex_timedlock (pthread_mutex_t *mutex,
 	  assume_other_futex_waiters |= FUTEX_WAITERS;
 
 	  /* Block using the futex.  */
-	  int err = lll_futex_timed_wait_bitset (&mutex->__data.__lock,
-	      oldval, abstime, FUTEX_CLOCK_REALTIME,
+	  int err = lll_futex_clock_wait_bitset (&mutex->__data.__lock,
+	      oldval, CLOCK_REALTIME, abstime,
 	      PTHREAD_ROBUST_MUTEX_PSHARED (mutex));
 	  /* The futex call timed out.  */
 	  if (err == -ETIMEDOUT)
diff --git a/nptl/pthread_rwlock_common.c b/nptl/pthread_rwlock_common.c
index 2560734..89ba21a 100644
--- a/nptl/pthread_rwlock_common.c
+++ b/nptl/pthread_rwlock_common.c
@@ -319,7 +319,7 @@ __pthread_rwlock_rdlock_full (pthread_rwlock_t *rwlock,
 		{
 		  int private = __pthread_rwlock_get_private (rwlock);
 		  int err = futex_abstimed_wait (&rwlock->__data.__readers,
-						 r, abstime, private);
+						 r, CLOCK_REALTIME, abstime, private);
 		  /* We ignore EAGAIN and EINTR.  On time-outs, we can just
 		     return because we don't need to clean up anything.  */
 		  if (err == ETIMEDOUT)
@@ -447,7 +447,7 @@ __pthread_rwlock_rdlock_full (pthread_rwlock_t *rwlock,
 	    continue;
 	  int err = futex_abstimed_wait (&rwlock->__data.__wrphase_futex,
 					 1 | PTHREAD_RWLOCK_FUTEX_USED,
-					 abstime, private);
+					 CLOCK_REALTIME, abstime, private);
 	  if (err == ETIMEDOUT)
 	    {
 	      /* If we timed out, we need to unregister.  If no read phase
@@ -707,7 +707,7 @@ __pthread_rwlock_wrlock_full (pthread_rwlock_t *rwlock,
 	  may_share_futex_used_flag = true;
 	  int err = futex_abstimed_wait (&rwlock->__data.__writers_futex,
 					 1 | PTHREAD_RWLOCK_FUTEX_USED,
-					 abstime, private);
+					 CLOCK_REALTIME, abstime, private);
 	  if (err == ETIMEDOUT)
 	    {
 	      if (prefer_writer)
@@ -806,7 +806,7 @@ __pthread_rwlock_wrlock_full (pthread_rwlock_t *rwlock,
 	    continue;
 	  int err = futex_abstimed_wait (&rwlock->__data.__wrphase_futex,
 					 PTHREAD_RWLOCK_FUTEX_USED,
-					 abstime, private);
+					 CLOCK_REALTIME, abstime, private);
 	  if (err == ETIMEDOUT)
 	    {
 	      if (rwlock->__data.__flags != PTHREAD_RWLOCK_PREFER_READER_NP)
diff --git a/nptl/sem_waitcommon.c b/nptl/sem_waitcommon.c
index 5646bea..425d040 100644
--- a/nptl/sem_waitcommon.c
+++ b/nptl/sem_waitcommon.c
@@ -109,11 +109,13 @@ do_futex_wait (struct new_sem *sem, const struct timespec *abstime)
 
 #if __HAVE_64B_ATOMICS
   err = futex_abstimed_wait_cancelable (
-      (unsigned int *) &sem->data + SEM_VALUE_OFFSET, 0, abstime,
+      (unsigned int *) &sem->data + SEM_VALUE_OFFSET, 0,
+      CLOCK_REALTIME, abstime,
       sem->private);
 #else
   err = futex_abstimed_wait_cancelable (&sem->value, SEM_NWAITERS_MASK,
-					abstime, sem->private);
+					CLOCK_REALTIME, abstime,
+					sem->private);
 #endif
 
   return err;