nptl: Add POSIX-proposed sem_clockwait

Add:

 int sem_clockwait (sem_t *sem, clockid_t clock, const struct timespec
*abstime)

which behaves just like sem_timedwait, but measures abstime against the
specified clock. Currently supports CLOCK_REALTIME and CLOCK_MONOTONIC
and sets errno == EINVAL if any other clock is specified.

	* nptl/sem_waitcommon.c (do_futex_wait, __new_sem_wait_slow): Add
	clockid parameters to indicate the clock which abstime should be
	measured against.
	* nptl/sem_timedwait.c (sem_timedwait), nptl/sem_wait.c
	(__new_sem_wait): Pass CLOCK_REALTIME as clockid to
	__new_sem_wait_slow.
	* nptl/sem_clockwait.c: New file to implement sem_clockwait based
	on sem_timedwait.c.
	* nptl/Makefile: Add sem_clockwait.c source file. Add CFLAGS for
	sem_clockwait.c to match those used for sem_timedwait.c.
	* sysdeps/pthread/semaphore.h: Add sem_clockwait.
	* nptl/Versions (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/aarch64/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/alpha/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/arm/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/csky/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/hppa/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/i386/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/ia64/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/m68k/coldfire/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/m68k/m680x0/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/microblaze/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/mips/mips32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/mips/mips64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/nios2/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/riscv/rv64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/sh/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/x86_64/64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/x86_64/x32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* nptl/tst-sem17.c: Add new test for passing invalid clock to
	sem_clockwait.
	* nptl/tst-sem13.c, nptl/tst-sem5.c: Modify existing sem_timedwait
	tests to also test sem_clockwait.
	* manual/threads.texi: Document sem_clockwait.

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

1 files changed, 8 insertions, 7 deletions

diff --git a/nptl/sem_waitcommon.c b/nptl/sem_waitcommon.c
index 425d040dd4..cad56e996d 100644
--- a/nptl/sem_waitcommon.c
+++ b/nptl/sem_waitcommon.c
@@ -103,19 +103,19 @@ __sem_wait_cleanup (void *arg)
    users don't seem to need it.  */
 static int
 __attribute__ ((noinline))
-do_futex_wait (struct new_sem *sem, const struct timespec *abstime)
+do_futex_wait (struct new_sem *sem, clockid_t clockid,
+	       const struct timespec *abstime)
 {
   int err;
 
 #if __HAVE_64B_ATOMICS
   err = futex_abstimed_wait_cancelable (
       (unsigned int *) &sem->data + SEM_VALUE_OFFSET, 0,
-      CLOCK_REALTIME, abstime,
+      clockid, abstime,
       sem->private);
 #else
   err = futex_abstimed_wait_cancelable (&sem->value, SEM_NWAITERS_MASK,
-					CLOCK_REALTIME, abstime,
-					sem->private);
+					clockid, abstime, sem->private);
 #endif
 
   return err;
@@ -162,7 +162,8 @@ __new_sem_wait_fast (struct new_sem *sem, int definitive_result)
 /* Slow path that blocks.  */
 static int
 __attribute__ ((noinline))
-__new_sem_wait_slow (struct new_sem *sem, const struct timespec *abstime)
+__new_sem_wait_slow (struct new_sem *sem, clockid_t clockid,
+		     const struct timespec *abstime)
 {
   int err = 0;
 
@@ -180,7 +181,7 @@ __new_sem_wait_slow (struct new_sem *sem, const struct timespec *abstime)
       /* If there is no token available, sleep until there is.  */
       if ((d & SEM_VALUE_MASK) == 0)
 	{
-	  err = do_futex_wait (sem, abstime);
+	  err = do_futex_wait (sem, clockid, abstime);
 	  /* A futex return value of 0 or EAGAIN is due to a real or spurious
 	     wake-up, or due to a change in the number of tokens.  We retry in
 	     these cases.
@@ -281,7 +282,7 @@ __new_sem_wait_slow (struct new_sem *sem, const struct timespec *abstime)
 	  if ((v >> SEM_VALUE_SHIFT) == 0)
 	    {
 	      /* See __HAVE_64B_ATOMICS variant.  */
-	      err = do_futex_wait(sem, abstime);
+	      err = do_futex_wait (sem, clockid, abstime);
 	      if (err == ETIMEDOUT || err == EINTR)
 		{
 		  __set_errno (err);