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, 18 insertions, 5 deletions

diff --git a/nptl/tst-sem5.c b/nptl/tst-sem5.c
index 396222b..63b1355 100644
--- a/nptl/tst-sem5.c
+++ b/nptl/tst-sem5.c
@@ -25,10 +25,15 @@
 #include <support/timespec.h>
 #include <support/xtime.h>
 
+/* A bogus clock value that tells run_test to use sem_timedwait rather than
+   sem_clockwait.  */
+#define CLOCK_USE_TIMEDWAIT (-1)
 
-static int
-do_test (void)
+static void
+do_test_clock (clockid_t clockid)
 {
+  const clockid_t clockid_for_get =
+    clockid == CLOCK_USE_TIMEDWAIT ? CLOCK_REALTIME : clockid;
   sem_t s;
   struct timespec ts;
 
@@ -36,14 +41,22 @@ do_test (void)
   TEST_COMPARE (TEMP_FAILURE_RETRY (sem_wait (&s)), 0);
 
   /* We wait for half a second.  */
-  xclock_gettime (CLOCK_REALTIME, &ts);
+  xclock_gettime (clockid_for_get, &ts);
   ts = timespec_add (ts, make_timespec (0, TIMESPEC_HZ/2));
 
   errno = 0;
-  TEST_COMPARE (TEMP_FAILURE_RETRY (sem_timedwait (&s, &ts)), -1);
+  TEST_COMPARE (TEMP_FAILURE_RETRY ((clockid == CLOCK_USE_TIMEDWAIT)
+                                    ? sem_timedwait (&s, &ts)
+                                    : sem_clockwait (&s, clockid, &ts)), -1);
   TEST_COMPARE (errno, ETIMEDOUT);
-  TEST_TIMESPEC_NOW_OR_AFTER (CLOCK_REALTIME, ts);
+  TEST_TIMESPEC_NOW_OR_AFTER (clockid_for_get, ts);
+}
 
+static int do_test (void)
+{
+  do_test_clock (CLOCK_USE_TIMEDWAIT);
+  do_test_clock (CLOCK_REALTIME);
+  do_test_clock (CLOCK_MONOTONIC);
   return 0;
 }