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Diffstat (limited to 'sysdeps/unix/sysv/linux/clock_getres.c')
-rw-r--r--sysdeps/unix/sysv/linux/clock_getres.c185
1 files changed, 151 insertions, 34 deletions
diff --git a/sysdeps/unix/sysv/linux/clock_getres.c b/sysdeps/unix/sysv/linux/clock_getres.c
index 442fbd5705..813d3ebbf9 100644
--- a/sysdeps/unix/sysv/linux/clock_getres.c
+++ b/sysdeps/unix/sysv/linux/clock_getres.c
@@ -1,4 +1,5 @@
-/* Copyright (C) 2003 Free Software Foundation, Inc.
+/* clock_getres -- Get the resolution of a POSIX clockid_t.  Linux version.
+   Copyright (C) 2003,2004,2005,2006 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -17,60 +18,176 @@
    02111-1307 USA.  */
 
 #include <sysdep.h>
+#include <errno.h>
+#include <time.h>
+#include "kernel-posix-cpu-timers.h"
+#include <kernel-features.h>
 
-#include "kernel-features.h"
+#ifndef HAVE_CLOCK_GETRES_VSYSCALL
+# undef INTERNAL_VSYSCALL
+# define INTERNAL_VSYSCALL INTERNAL_SYSCALL
+# undef INLINE_VSYSCALL
+# define INLINE_VSYSCALL INLINE_SYSCALL
+#else
+# include <bits/libc-vdso.h>
+#endif
 
+#define SYSCALL_GETRES \
+  retval = INLINE_VSYSCALL (clock_getres, 2, clock_id, res); \
+  break
 
 #ifdef __ASSUME_POSIX_TIMERS
+
 /* This means the REALTIME and MONOTONIC clock are definitely
    supported in the kernel.  */
-# define SYSDEP_GETRES \
+# define SYSDEP_GETRES							      \
+  SYSDEP_GETRES_CPUTIME							      \
   case CLOCK_REALTIME:							      \
   case CLOCK_MONOTONIC:							      \
-    retval = INLINE_SYSCALL (clock_getres, 2, clock_id, res);		      \
-    break
+    SYSCALL_GETRES
+
+# define __libc_missing_posix_timers 0
 #elif defined __NR_clock_getres
 /* Is the syscall known to exist?  */
 extern int __libc_missing_posix_timers attribute_hidden;
 
+static inline int
+maybe_syscall_getres (clockid_t clock_id, struct timespec *res)
+{
+  int e = EINVAL;
+
+  if (!__libc_missing_posix_timers)
+    {
+      INTERNAL_SYSCALL_DECL (err);
+      int r = INTERNAL_VSYSCALL (clock_getres, err, 2, clock_id, res);
+      if (!INTERNAL_SYSCALL_ERROR_P (r, err))
+	return 0;
+
+      e = INTERNAL_SYSCALL_ERRNO (r, err);
+      if (e == ENOSYS)
+	{
+	  __libc_missing_posix_timers = 1;
+	  e = EINVAL;
+	}
+    }
+
+  return e;
+}
+
 /* The REALTIME and MONOTONIC clock might be available.  Try the
    syscall first.  */
-# define SYSDEP_GETRES \
+# define SYSDEP_GETRES							      \
+  SYSDEP_GETRES_CPUTIME							      \
   case CLOCK_REALTIME:							      \
   case CLOCK_MONOTONIC:							      \
-    {									      \
-      int e = EINVAL;							      \
-									      \
-      if (!__libc_missing_posix_timers)					      \
-	{								      \
-	  INTERNAL_SYSCALL_DECL (err);					      \
-	  int r = INTERNAL_SYSCALL (clock_getres, err, 2, clock_id, res);     \
-	  if (!INTERNAL_SYSCALL_ERROR_P (r, err))			      \
-	    {								      \
-	      retval = 0;						      \
-	      break;							      \
-	    }								      \
-									      \
-	  e = INTERNAL_SYSCALL_ERRNO (r, err);				      \
-	  if (e == ENOSYS)						      \
-	    {								      \
-	      __libc_missing_posix_timers = 1;				      \
-	      e = EINVAL;						      \
-	    }								      \
-	}								      \
-									      \
-      /* Fallback code.  */						      \
-      if (e == EINVAL && clock_id == CLOCK_REALTIME)			      \
-	HANDLE_REALTIME;						      \
-      else								      \
-	__set_errno (e);						      \
-    }									      \
-    break
+    retval = maybe_syscall_getres (clock_id, res);			      \
+    if (retval == 0)							      \
+      break;								      \
+    /* Fallback code.  */						      \
+    if (retval == EINVAL && clock_id == CLOCK_REALTIME)			      \
+      retval = realtime_getres (res);					      \
+    else								      \
+      {									      \
+	__set_errno (retval);						      \
+	retval = -1;							      \
+      }									      \
+    break;
 #endif
 
 #ifdef __NR_clock_getres
 /* We handled the REALTIME clock here.  */
 # define HANDLED_REALTIME	1
+# define HANDLED_CPUTIME	1
+
+# if __ASSUME_POSIX_CPU_TIMERS > 0
+
+#  define SYSDEP_GETRES_CPU SYSCALL_GETRES
+#  define SYSDEP_GETRES_CPUTIME	/* Default catches them too.  */
+
+# else
+
+extern int __libc_missing_posix_cpu_timers attribute_hidden;
+
+static int
+maybe_syscall_getres_cpu (clockid_t clock_id, struct timespec *res)
+{
+  int e = EINVAL;
+
+  if (!__libc_missing_posix_cpu_timers)
+    {
+      INTERNAL_SYSCALL_DECL (err);
+      int r = INTERNAL_VSYSCALL (clock_getres, err, 2, clock_id, res);
+      if (!INTERNAL_SYSCALL_ERROR_P (r, err))
+	return 0;
+
+      e = INTERNAL_SYSCALL_ERRNO (r, err);
+# ifndef __ASSUME_POSIX_TIMERS
+      if (e == ENOSYS)
+	{
+	  __libc_missing_posix_timers = 1;
+	  __libc_missing_posix_cpu_timers = 1;
+	  e = EINVAL;
+	}
+      else
+# endif
+	{
+	  if (e == EINVAL)
+	    {
+	      /* Check whether the kernel supports CPU clocks at all.
+		 If not, record it for the future.  */
+	      r = INTERNAL_VSYSCALL (clock_getres, err, 2,
+				    MAKE_PROCESS_CPUCLOCK (0, CPUCLOCK_SCHED),
+				    NULL);
+	      if (INTERNAL_SYSCALL_ERROR_P (r, err))
+		__libc_missing_posix_cpu_timers = 1;
+	    }
+	}
+    }
+
+  return e;
+}
+
+#  define SYSDEP_GETRES_CPU						      \
+  retval = maybe_syscall_getres_cpu (clock_id, res);			      \
+  if (retval == 0)							      \
+    break;								      \
+  if (retval != EINVAL || !__libc_missing_posix_cpu_timers)		      \
+    {									      \
+      __set_errno (retval);						      \
+      retval = -1;							      \
+      break;								      \
+    }									      \
+  retval = -1 /* Otherwise continue on to the HP_TIMING version.  */;
+
+static inline int
+maybe_syscall_getres_cputime (clockid_t clock_id, struct timespec *res)
+{
+  return maybe_syscall_getres_cpu
+    (clock_id == CLOCK_THREAD_CPUTIME_ID
+     ? MAKE_THREAD_CPUCLOCK (0, CPUCLOCK_SCHED)
+     : MAKE_PROCESS_CPUCLOCK (0, CPUCLOCK_SCHED),
+     res);
+}
+
+#  define SYSDEP_GETRES_CPUTIME						      \
+    case CLOCK_PROCESS_CPUTIME_ID:					      \
+    case CLOCK_THREAD_CPUTIME_ID:					      \
+      retval = maybe_syscall_getres_cputime (clock_id, res);		      \
+      if (retval == 0)							      \
+	break;								      \
+      if (retval != EINVAL || !__libc_missing_posix_cpu_timers)		      \
+	{								      \
+	  __set_errno (retval);						      \
+	  retval = -1;							      \
+	  break;							      \
+	}								      \
+      retval = hp_timing_getres (res);					      \
+      break;
+#  if !HP_TIMING_AVAIL
+#   define hp_timing_getres(res) (__set_errno (EINVAL), -1)
+#  endif
+
+# endif
 #endif
 
 #include <sysdeps/posix/clock_getres.c>