[[PATCH,RFC,2] 17/63] Y2038: add function __clock_getres64
Commit Message
---
include/time.h | 2 +
sysdeps/posix/clock_getres.c | 96 +++++++++++++++++++++++++++++++++-
sysdeps/unix/sysv/linux/clock_getres.c | 60 +++++++++++++++++++++
time/Versions | 1 +
4 files changed, 158 insertions(+), 1 deletion(-)
@@ -37,6 +37,8 @@ extern int __clock_gettime64 (clockid_t __clock_id,
struct __timespec64 *__tp) __THROW;
extern int __clock_settime64 (clockid_t __clock_id,
const struct __timespec64 *__tp) __THROW;
+extern int __clock_getres64 (clockid_t __clock_id,
+ struct __timespec64 *__res) __THROW;
/* Now define the internal interfaces. */
struct tm;
@@ -23,7 +23,6 @@
#include <sys/param.h>
#include <libc-internal.h>
-
#if HP_TIMING_AVAIL
static long int nsec; /* Clock frequency of the processor. */
@@ -53,6 +52,33 @@ hp_timing_getres (struct timespec *res)
return 0;
}
+
+static int
+hp_timing_getres64 (struct __timespec64 *res)
+{
+ if (__glibc_unlikely (nsec == 0))
+ {
+ hp_timing_t freq;
+
+ /* This can only happen if we haven't initialized the `nsec'
+ variable yet. Do this now. We don't have to protect this
+ code against multiple execution since all of them should
+ lead to the same result. */
+ freq = __get_clockfreq ();
+ if (__glibc_unlikely (freq == 0))
+ /* Something went wrong. */
+ return -1;
+
+ nsec = MAX (UINT64_C (1000000000) / freq, 1);
+ }
+
+ /* Fill in the values.
+ The seconds are always zero (unless we have a 1Hz machine). */
+ res->tv_sec = 0;
+ res->tv_nsec = nsec;
+
+ return 0;
+}
#endif
static inline int
@@ -73,6 +99,28 @@ realtime_getres (struct timespec *res)
return -1;
}
+/* Check that we are built with a 64-bit-time kernel */
+#ifdef __NR_clock_getres64
+
+static inline int
+realtime_getres64 (struct __timespec64 *res)
+{
+ long int clk_tck = sysconf (_SC_CLK_TCK);
+
+ if (__glibc_likely (clk_tck != -1))
+ {
+ /* This implementation assumes that the realtime clock has a
+ resolution higher than 1 second. This is the case for any
+ reasonable implementation. */
+ res->tv_sec = 0;
+ res->tv_nsec = 1000000000 / clk_tck;
+ return 0;
+ }
+
+ return -1;
+}
+
+#endif
/* Get resolution of clock. */
int
@@ -116,3 +164,49 @@ __clock_getres (clockid_t clock_id, struct timespec *res)
return retval;
}
weak_alias (__clock_getres, clock_getres)
+
+int
+__clock_getres64 (clockid_t clock_id, struct __timespec64 *res)
+{
+ int retval = -1;
+
+ switch (clock_id)
+ {
+#ifdef SYSDEP_GETRES64
+ SYSDEP_GETRES64;
+#endif
+
+/* Check that we are built with a 64-bit-time kernel */
+#ifdef __NR_clock_getres64
+
+# ifndef HANDLED_REALTIME64
+ case CLOCK_REALTIME64:
+ retval = realtime_getres64 (res);
+ break;
+# endif /* handled REALTIME */
+
+#endif
+
+ default:
+#ifdef SYSDEP_GETRES_CPU64
+ SYSDEP_GETRES_CPU64;
+#endif
+#if HP_TIMING_AVAIL
+ if ((clock_id & ((1 << CLOCK_IDFIELD_SIZE) - 1))
+ == CLOCK_THREAD_CPUTIME_ID)
+ retval = hp_timing_getres64 (res);
+ else
+#endif
+ __set_errno (EINVAL);
+ break;
+
+#if HP_TIMING_AVAIL && !defined HANDLED_CPUTIME
+ case CLOCK_PROCESS_CPUTIME_ID:
+ case CLOCK_THREAD_CPUTIME_ID:
+ retval = hp_timing_getres64 (res);
+ break;
+#endif
+ }
+
+ return retval;
+}
@@ -48,4 +48,64 @@
#define SYSDEP_GETRES_CPU SYSCALL_GETRES
#define SYSDEP_GETRES_CPUTIME /* Default catches them too. */
+/* The 64-bit version */
+
+/* Check that we are built with a 64-bit-time kernel */
+#ifdef __NR_clock_getres64
+
+extern int __y2038_linux_support;
+
+#define SYSCALL_GETRES64 \
+ if (__y2038_linux_support) \
+ { \
+ retval = INLINE_VSYSCALL (clock_getres64, 2, clock_id, res); \
+ } \
+ else \
+ { \
+ retval = -1; \
+ errno = ENOSYS; \
+ } \
+ if (retval == -1 && errno == ENOSYS) \
+ { \
+ retval = INLINE_VSYSCALL (clock_getres, 2, clock_id, &ts32); \
+ if (retval==0) \
+ { \
+ timespec_to_timespec64(&ts32, res); \
+ res->tv_pad = 0; \
+ } \
+ } \
+ break
+
+#else
+
+#define SYSCALL_GETRES64 \
+ retval = INLINE_VSYSCALL (clock_getres, 2, clock_id, &ts32); \
+ if (retval==0) \
+ { \
+ timespec_to_timespec64(&ts32, res); \
+ res->tv_pad = 0; \
+ } \
+ break
+
+#endif
+
+/* The REALTIME and MONOTONIC clock are definitely supported in the
+ kernel. */
+#define SYSDEP_GETRES64 \
+ SYSDEP_GETRES_CPUTIME64 \
+ case CLOCK_REALTIME: \
+ case CLOCK_MONOTONIC: \
+ case CLOCK_MONOTONIC_RAW: \
+ case CLOCK_REALTIME_COARSE: \
+ case CLOCK_MONOTONIC_COARSE: \
+ SYSCALL_GETRES64
+
+/* We handled the REALTIME clock here. */
+#define HANDLED_REALTIME64 1
+#define HANDLED_CPUTIME64 1
+
+#define SYSDEP_GETRES_CPU64 SYSCALL_GETRES64
+#define SYSDEP_GETRES_CPUTIME64 \
+ struct timespec ts32;
+
#include <sysdeps/posix/clock_getres.c>
@@ -76,5 +76,6 @@ libc {
__vdso_clock_gettime64;
__y2038_kernel_support;
__clock_settime64;
+ __clock_getres64;
}
}