[RFC v4 02/24] sysdeps/nanosleep: Use clock_nanosleep_time64 if avaliable

[Alistair Francis <alistair dot francis at wdc dot com>]

The nanosleep syscall is not supported on newer 32-bit platforms (such
as RV32). To fix this issue let's use clock_nanosleep_time64 if it is
avaliable.

Let's use CLOCK_REALTIME when calling clock_nanosleep_time64 as the
Linux specification says:
  "POSIX.1 specifies that nanosleep() should measure time against the
   CLOCK_REALTIME clock. However, Linux measures the time using the
   CLOCK_MONOTONIC clock. This probably does not matter, since the POSIX.1
   specification for clock_settime(2) says that discontinuous changes in
   CLOCK_REALTIME should not affect nanosleep()"

NOTE: We don't convert the struct timespec* remaining to a 64-bit value,
we need to kernel to provide __NR_clock_nanosleep_time64 and __TIMESIZE == 64
to get a 64bit timespec.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
---
 ChangeLog                                    |  6 ++
 nptl/thrd_sleep.c                            | 60 +++++++++++++++-
 sysdeps/unix/sysv/linux/clock_nanosleep.c    | 61 +++++++++++++++-
 sysdeps/unix/sysv/linux/nanosleep.c          | 75 ++++++++++++++++++++
 sysdeps/unix/sysv/linux/nanosleep_nocancel.c | 47 ++++++++++++
 5 files changed, 243 insertions(+), 6 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index a8186db3944..aab4469b3d4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1419,6 +1419,12 @@
 
 	* support/xtime.h: Add xclock_now() helper function.
 
+2019-06-21  Alistair Francis  <alistair.francis@wdc.com>
+
+	* nptl/thrd_sleep.c: Use clock_nanosleep_time64 instead of nanosleep.
+	* sysdeps/unix/sysv/linux/nanosleep.c: Likewise.
+	* sysdeps/unix/sysv/linux/nanosleep_nocancel.c: Likewise.
+
 2019-06-20  Dmitry V. Levin  <ldv@altlinux.org>
 	    Florian Weimer  <fweimer@redhat.com>
 
diff --git a/nptl/thrd_sleep.c b/nptl/thrd_sleep.c
index 07a51808df2..fc495b56c67 100644
--- a/nptl/thrd_sleep.c
+++ b/nptl/thrd_sleep.c
@@ -25,14 +25,68 @@ int
 thrd_sleep (const struct timespec* time_point, struct timespec* remaining)
 {
   INTERNAL_SYSCALL_DECL (err);
-  int ret = INTERNAL_SYSCALL_CANCEL (nanosleep, err, time_point, remaining);
+  int ret = -1;
+
+#ifdef __ASSUME_TIME64_SYSCALLS
+  ret = INTERNAL_SYSCALL_CANCEL (clock_nanosleep_time64, err, CLOCK_REALTIME,
+                                 0, time_point, remaining);
+#else
+# ifdef __NR_clock_nanosleep_time64
+#  if __TIMESIZE == 64
+  long int ret_64;
+
+  ret_64 = INTERNAL_SYSCALL_CANCEL (clock_nanosleep_time64, err, CLOCK_REALTIME,
+                                    0, time_point, remaining);
+
+  if (ret_64 == 0 || errno != ENOSYS)
+    ret = ret_64;
+#  else
+  timespec64 ts64;
+
+  ret = INTERNAL_SYSCALL_CANCEL (clock_nanosleep_time64, err,
+                                 CLOCK_REALTIME, 0, time_point,
+                                 ts64);
+
+  if (ret == 0 || errno != ENOSYS)
+    {
+      remaining->tv_sec = ts64.tv_sec;
+      remaining->tv_nsec = ts64.tv_nsec;
+    }
+#  endif /* __TIMESIZE == 64 */
+# endif /* __NR_clock_nanosleep_time64 */
+# if __TIMESIZE == 64
+  if (ret < 0)
+    {
+      struct timespec ts32, tr32;
+
+      if (! in_time_t_range (time_point->tv_sec))
+        {
+          __set_errno (EOVERFLOW);
+          return -1;
+        }
+
+      valid_timespec64_to_timespec (time_point, &ts32);
+      ret =  INTERNAL_SYSCALL_CANCEL (nanosleep, err, &ts32, &tr32);
+
+      if (ret == 0 || errno != ENOSYS)
+        {
+          remaining->tv_sec = tr32.tv_sec;
+          remaining->tv_nsec = tr32.tv_nsec;
+        }
+    }
+# else
+  if (ret < 0)
+      ret =  INTERNAL_SYSCALL_CANCEL (nanosleep, err, time_point, remaining);
+# endif /* __TIMESIZE == 64 */
+#endif /* __ASSUME_TIME64_SYSCALLS */
+
   if (INTERNAL_SYSCALL_ERROR_P (ret, err))
     {
       /* C11 states thrd_sleep function returns -1 if it has been interrupted
-	 by a signal, or a negative value if it fails.  */
+         by a signal, or a negative value if it fails.  */
       ret = INTERNAL_SYSCALL_ERRNO (ret, err);
       if (ret == EINTR)
-	return -1;
+        return -1;
       return -2;
     }
   return 0;
diff --git a/sysdeps/unix/sysv/linux/clock_nanosleep.c b/sysdeps/unix/sysv/linux/clock_nanosleep.c
index 0cb6614dc92..4f9fc8b47b6 100644
--- a/sysdeps/unix/sysv/linux/clock_nanosleep.c
+++ b/sysdeps/unix/sysv/linux/clock_nanosleep.c
@@ -21,13 +21,14 @@
 #include <sysdep-cancel.h>
 #include "kernel-posix-cpu-timers.h"
 
-
 /* We can simply use the syscall.  The CPU clocks are not supported
    with this function.  */
 int
 __clock_nanosleep (clockid_t clock_id, int flags, const struct timespec *req,
 		   struct timespec *rem)
 {
+  int r = -1;
+
   if (clock_id == CLOCK_THREAD_CPUTIME_ID)
     return EINVAL;
   if (clock_id == CLOCK_PROCESS_CPUTIME_ID)
@@ -36,8 +37,62 @@ __clock_nanosleep (clockid_t clock_id, int flags, const struct timespec *req,
   /* If the call is interrupted by a signal handler or encounters an error,
      it returns a positive value similar to errno.  */
   INTERNAL_SYSCALL_DECL (err);
-  int r = INTERNAL_SYSCALL_CANCEL (clock_nanosleep, err, clock_id, flags,
-				   req, rem);
+
+
+#ifdef __ASSUME_TIME64_SYSCALLS
+  r = INTERNAL_SYSCALL_CANCEL (clock_nanosleep_time64, err, clock_id,
+                               flags, req, rem);
+#else
+# ifdef __NR_clock_nanosleep_time64
+#  if __TIMESIZE == 64
+  long int ret_64;
+
+  ret_64 = INTERNAL_SYSCALL_CANCEL (clock_nanosleep_time64, err, clock_id,
+                                    flags, req, rem);
+
+  if (ret_64 == 0 || errno != ENOSYS)
+    r = ret_64;
+#  else
+  timespec64 ts64;
+
+  r = INTERNAL_SYSCALL_CANCEL (clock_nanosleep_time64, err,
+                               clock_id, flags, req,
+                               ts64);
+
+  if (r == 0 || errno != ENOSYS)
+    {
+      rem->tv_sec = ts64.tv_sec;
+      rem->tv_nsec = ts64.tv_nsec;
+      return r;
+    }
+#  endif /* __TIMESIZE == 64 */
+# endif /* __NR_clock_nanosleep_time64 */
+# if __TIMESIZE == 64
+  struct timespec ts32, tr32;
+
+  if (r < 0)
+    {
+      if (! in_time_t_range (req->tv_sec))
+        {
+          __set_errno (EOVERFLOW);
+          return -1;
+        }
+
+      valid_timespec64_to_timespec (req, &ts32);
+      r =  INTERNAL_SYSCALL_CANCEL (clock_nanosleep, err, &ts32, &tr32);
+
+      if (r == 0 || errno != ENOSYS)
+        {
+          rem->tv_sec = tr32.tv_sec;
+          rem->tv_nsec = tr32.tv_nsec;
+        }
+    }
+# else
+  if (r < 0)
+      r =  INTERNAL_SYSCALL_CANCEL (clock_nanosleep, err, req, rem);
+# endif /* __TIMESIZE == 64 */
+#endif /* __ASSUME_TIME64_SYSCALLS */
+
   return (INTERNAL_SYSCALL_ERROR_P (r, err)
 	  ? INTERNAL_SYSCALL_ERRNO (r, err) : 0);
 }
diff --git a/sysdeps/unix/sysv/linux/nanosleep.c b/sysdeps/unix/sysv/linux/nanosleep.c
index f14ae565af5..a894ccbc6dd 100644
--- a/sysdeps/unix/sysv/linux/nanosleep.c
+++ b/sysdeps/unix/sysv/linux/nanosleep.c
@@ -20,12 +20,87 @@
 #include <sysdep-cancel.h>
 #include <not-cancel.h>
 
+#if defined(__ASSUME_TIME64_SYSCALLS) || defined(__NR_clock_nanosleep_time64)
+static int
+__nanosleep_time64_64 (const struct timespec *requested_time,
+                       struct timespec *remaining)
+{
+  return SYSCALL_CANCEL (clock_nanosleep_time64, CLOCK_REALTIME, 0,
+                         requested_time, remaining);
+}
+
+#if __TIMESIZE == 32
+struct timespec64
+{
+  long long int tv_sec;   /* Seconds.  */
+  long int tv_nsec;  /* Nanoseconds.  */
+};
+
+static int
+__nanosleep_time64_32 (const struct timespec *requested_time,
+                       struct timespec *remaining)
+{
+  timespec64 ts;
+
+  long int ret = SYSCALL_CANCEL (clock_nanosleep_time64, CLOCK_REALTIME, 0,
+                                 requested_time, &ts);
+
+  if (ret == 0 || errno != ENOSYS)
+    {
+      remaining->tv_sec = ts.tv_sec;
+      remaining->tv_nsec = ts.tv_nsec;
+    }
+
+  return ret;
+}
+#endif
+#endif
+
 /* Pause execution for a number of nanoseconds.  */
 int
 __nanosleep (const struct timespec *requested_time,
 	     struct timespec *remaining)
 {
+#ifdef __ASSUME_TIME64_SYSCALLS
+  return __nanosleep_time64_64 (requested_time, remaining);
+#else
+  long int ret;
+# ifdef __NR_clock_nanosleep_time64
+#  if __TIMESIZE == 64
+  ret = __nanosleep_time64_64 (requested_time, remaining);
+
+  if (ret == 0 || errno != ENOSYS)
+    return ret;
+#  else
+  ret = __nanosleep_time64_32 (requested_time, remaining);
+
+  if (ret == 0 || errno != ENOSYS)
+    return ret;
+#  endif /* __TIMESIZE == 64 */
+# endif /* __NR_clock_nanosleep_time64 */
+# if __TIMESIZE == 64
+  struct timespec ts32, tr32;
+
+  if (! in_time_t_range (requested_time->tv_sec))
+    {
+      __set_errno (EOVERFLOW);
+      return -1;
+    }
+
+  valid_timespec64_to_timespec (requested_time, &ts32);
+  ret =  SYSCALL_CANCEL (nanosleep, &ts32, &tr32);
+
+  if (ret == 0 || errno != ENOSYS)
+    {
+      remaining->tv_sec = tr32.tv_sec;
+      remaining->tv_nsec = tr32.tv_nsec;
+    }
+
+  return ret;
+# else
   return SYSCALL_CANCEL (nanosleep, requested_time, remaining);
+# endif /* __TIMESIZE == 64 */
+#endif /* __ASSUME_TIME64_SYSCALLS */
 }
 hidden_def (__nanosleep)
 weak_alias (__nanosleep, nanosleep)
diff --git a/sysdeps/unix/sysv/linux/nanosleep_nocancel.c b/sysdeps/unix/sysv/linux/nanosleep_nocancel.c
index 122ba627ff3..f04e229e5ec 100644
--- a/sysdeps/unix/sysv/linux/nanosleep_nocancel.c
+++ b/sysdeps/unix/sysv/linux/nanosleep_nocancel.c
@@ -24,6 +24,53 @@ int
 __nanosleep_nocancel (const struct timespec *requested_time,
 		      struct timespec *remaining)
 {
+#ifdef __ASSUME_TIME64_SYSCALLS
+  return INLINE_SYSCALL_CALL (clock_nanosleep_time64, CLOCK_REALTIME, 0,
+                         requested_time, remaining);
+#else
+  long int ret;
+# ifdef __NR_clock_nanosleep_time64
+#  if __TIMESIZE == 64
+  ret = INLINE_SYSCALL_CALL (clock_nanosleep_time64, CLOCK_REALTIME, 0,
+                             requested_time, remaining);
+
+  if (ret_64 == 0 || errno != ENOSYS)
+    return ret;
+#  else
+  timespec64 ts64;
+
+  ret = INLINE_SYSCALL_CALL (clock_nanosleep_time64, CLOCK_REALTIME, 0,
+                             time_point, ts64);
+
+  if (ret == 0 || errno != ENOSYS)
+    {
+      remaining->tv_sec = ts64.tv_sec;
+      remaining->tv_nsec = ts64.tv_nsec;
+      return ret;
+    }
+#  endif /* __TIMESIZE == 64 */
+# endif /* __NR_clock_nanosleep_time64 */
+# if __TIMESIZE == 64
+  struct timespec ts32, tr32;
+
+  if (! in_time_t_range (requested_time->tv_sec))
+    {
+      __set_errno (EOVERFLOW);
+      return -1;
+    }
+
+  valid_timespec64_to_timespec (requested_time, &ts32);
+  ret = INLINE_SYSCALL_CALL (nanosleep, &ts32, &tr32);
+
+  if (ret == 0 || errno != ENOSYS)
+    {
+      remaining->tv_sec = tr32.tv_sec;
+      remaining->tv_nsec = tr32.tv_nsec;
+    }
+  return ret;
+# else
   return INLINE_SYSCALL_CALL (nanosleep, requested_time, remaining);
+# endif /* __TIMESIZE == 64 */
+#endif /* __ASSUME_TIME64_SYSCALLS */
 }
 hidden_def (__nanosleep_nocancel)
-- 
2.22.0