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2005-04-27 Roland McGrath <roland@redhat.com>
	* sysdeps/unix/sysv/linux/kernel-posix-cpu-timers.h: New file.
	* sysdeps/unix/sysv/linux/clock_getcpuclockid.c: New file.
	* sysdeps/unix/sysv/linux/ia64/clock_getcpuclockid.c
	(HAS_CPUCLOCK): New macro.
	(clock_getcpuclockid): Function removed.
	#include the new linux file to define it instead.
	* sysdeps/unix/clock_gettime.c [HP_TIMING_AVAIL] (hp_timing_gettime):
	New function, broken out of ...
	(clock_gettime) [HP_TIMING_AVAIL]: ... here.  Call it.
	(realtime_gettime): New function, broken out of ...
	(clock_gettime) [! HANDLED_REALTIME]: ... here.  Call it.
	(clock_gettime) [SYSDEP_GETTIME_CPU]: Use new macro in default case.
	* sysdeps/unix/sysv/linux/clock_gettime.c (SYSCALL_GETTIME): New macro.
	(SYSDEP_GETTIME_CPUTIME): New macro.
	(SYSDEP_GETTIME): Use both.
	[! __ASSUME_POSIX_TIMERS] (maybe_syscall_gettime): New function, broken
	out of ...
	(SYSDEP_GETTIME): ... here.  Use it.
	[__NR_clock_gettime] (HANDLED_CPUTIME): Define it.
	(SYSDEP_GETTIME_CPUTIME): New macro.  Handle CPU timers by trying
	kernel support and falling back to hp-timing code.
	* sysdeps/posix/clock_getres.c
	[HP_TIMING_AVAIL] (hp_timing_getres): New function, broken out of ...
	(clock_getres) [HP_TIMING_AVAIL]: ... here.  Call it.
	(realtime_getres): New function, broken out of ...
	(clock_getres) [! HANDLED_REALTIME]: ... here.  Call it.
	(clock_getres) [SYSDEP_GETRES_CPU]: Use new macro in default case.
	* sysdeps/unix/sysv/linux/clock_getres.c (SYSCALL_GETRES): New macro.
	(SYSDEP_GETRES_CPUTIME): New macro.
	(SYSDEP_GETRES): Use both.
	[! __ASSUME_POSIX_TIMERS] (maybe_syscall_getres): New function, broken
	out of ...
	(SYSDEP_GETRES): ... here.  Use it.
	[__NR_clock_getres] (HANDLED_CPUTIME): Define it.
	(SYSDEP_GETRES_CPUTIME): New macro.  Handle CPU timers by trying
	kernel support and falling back to hp-timing code.
	* sysdeps/unix/sysv/linux/clock_nanosleep.c: Handle
	CLOCK_PROCESS_CPUTIME_ID and CLOCK_PROCESS_THREAD_ID specially,
	translating to the kernel clockid_t for our own process/thread clock.
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Roland McGrath committed Apr 27, 2005
1 parent 0f888d8 commit 2f4f3bd
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Showing 8 changed files with 549 additions and 195 deletions.
111 changes: 60 additions & 51 deletions sysdeps/posix/clock_getres.c
@@ -1,4 +1,5 @@
/* Copyright (C) 1999, 2000, 2001, 2003 Free Software Foundation, Inc.
/* clock_getres -- Get the resolution of a POSIX clockid_t.
Copyright (C) 1999, 2000, 2001, 2003, 2004 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
Expand All @@ -24,11 +25,55 @@
#include <libc-internal.h>


#if HP_TIMING_AVAIL && !defined HANDLED_CPUTIME
/* Clock frequency of the processor. */
static long int nsec;
#if HP_TIMING_AVAIL
static long int nsec; /* Clock frequency of the processor. */

static inline int
hp_timing_getres (struct timespec *res)
{
if (__builtin_expect (nsec == 0, 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 (__builtin_expect (freq == 0, 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
realtime_getres (struct timespec *res)
{
long int clk_tck = sysconf (_SC_CLK_TCK);

if (__builtin_expect (clk_tck != -1, 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;
}


/* Get resolution of clock. */
int
Expand All @@ -38,69 +83,33 @@ clock_getres (clockid_t clock_id, struct timespec *res)

switch (clock_id)
{
#define HANDLE_REALTIME \
do { \
long int clk_tck = sysconf (_SC_CLK_TCK); \
\
if (__builtin_expect (clk_tck != -1, 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; \
\
retval = 0; \
} \
} while (0)

#ifdef SYSDEP_GETRES
SYSDEP_GETRES;
#endif

#ifndef HANDLED_REALTIME
case CLOCK_REALTIME:
HANDLE_REALTIME;
retval = realtime_getres (res);
break;
#endif /* handled REALTIME */

default:
#ifdef SYSDEP_GETRES_CPU
SYSDEP_GETRES_CPU;
#endif
#if HP_TIMING_AVAIL
if ((clock_id & ((1 << CLOCK_IDFIELD_SIZE) - 1))
!= CLOCK_THREAD_CPUTIME_ID)
== CLOCK_THREAD_CPUTIME_ID)
retval = hp_timing_getres (res);
else
#endif
{
__set_errno (EINVAL);
break;
}
__set_errno (EINVAL);
break;

#if HP_TIMING_AVAIL && !defined HANDLED_CPUTIME
/* FALLTHROUGH. */
case CLOCK_PROCESS_CPUTIME_ID:
{
if (__builtin_expect (nsec == 0, 0))
{
hp_timing_t freq;

/* This can only happen if we haven't initialized the `freq'
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 (__builtin_expect (freq == 0, 0))
/* Something went wrong. */
break;

nsec = MAX (UINT64_C (1000000000) / freq, 1);
}

/* File in the values. The seconds are always zero (unless we
have a 1Hz machine). */
res->tv_sec = 0;
res->tv_nsec = nsec;

retval = 0;
}
case CLOCK_THREAD_CPUTIME_ID:
retval = hp_timing_getres (res);
break;
#endif
}
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117 changes: 62 additions & 55 deletions sysdeps/unix/clock_gettime.c
@@ -1,4 +1,5 @@
/* Copyright (C) 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
/* clock_gettime -- Get the current time from a POSIX clockid_t. Unix version.
Copyright (C) 1999,2000,2001,2002,2003,2004 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
Expand Down Expand Up @@ -35,9 +36,58 @@ static hp_timing_t freq;
extern int __pthread_clock_gettime (clockid_t clock_id, hp_timing_t freq,
struct timespec *tp)
__attribute__ ((__weak__));

static int
hp_timing_gettime (clockid_t clock_id, struct timespec *tp)
{
hp_timing_t tsc;

if (__builtin_expect (freq == 0, 0))
{
/* This can only happen if we haven't initialized the `freq'
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 (__builtin_expect (freq == 0, 0))
/* Something went wrong. */
return -1;
}

if (clock_id != CLOCK_PROCESS_CPUTIME_ID
&& __pthread_clock_gettime != NULL)
return __pthread_clock_gettime (clock_id, freq, tp);

/* Get the current counter. */
HP_TIMING_NOW (tsc);

/* Compute the offset since the start time of the process. */
tsc -= GL(dl_cpuclock_offset);

/* Compute the seconds. */
tp->tv_sec = tsc / freq;

/* And the nanoseconds. This computation should be stable until
we get machines with about 16GHz frequency. */
tp->tv_nsec = ((tsc % freq) * UINT64_C (1000000000)) / freq;

return 0;
}
#endif


static inline int
realtime_gettime (struct timespec *tp)
{
struct timeval tv;
int retval = gettimeofday (&tv, NULL);
if (retval == 0)
/* Convert into `timespec'. */
TIMEVAL_TO_TIMESPEC (&tv, tp);
return retval;
}


/* Get current value of CLOCK and store it in TP. */
int
clock_gettime (clockid_t clock_id, struct timespec *tp)
Expand All @@ -46,15 +96,6 @@ clock_gettime (clockid_t clock_id, struct timespec *tp)

switch (clock_id)
{
#define HANDLE_REALTIME \
do { \
struct timeval tv; \
retval = gettimeofday (&tv, NULL); \
if (retval == 0) \
/* Convert into `timespec'. */ \
TIMEVAL_TO_TIMESPEC (&tv, tp); \
} while (0)

#ifdef SYSDEP_GETTIME
SYSDEP_GETTIME;
#endif
Expand All @@ -66,56 +107,22 @@ clock_gettime (clockid_t clock_id, struct timespec *tp)
#endif

default:
#ifdef SYSDEP_GETTIME_CPU
SYSDEP_GETTIME_CPU;
#endif
#if HP_TIMING_AVAIL
if ((clock_id & ((1 << CLOCK_IDFIELD_SIZE) - 1))
!= CLOCK_THREAD_CPUTIME_ID)
== CLOCK_THREAD_CPUTIME_ID)
retval = hp_timing_gettime (clock_id, tp);
else
#endif
{
__set_errno (EINVAL);
break;
}
__set_errno (EINVAL);
break;

#if HP_TIMING_AVAIL
/* FALLTHROUGH. */
#if HP_TIMING_AVAIL && !defined HANDLED_CPUTIME
case CLOCK_PROCESS_CPUTIME_ID:
{
hp_timing_t tsc;

if (__builtin_expect (freq == 0, 0))
{
/* This can only happen if we haven't initialized the `freq'
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 (__builtin_expect (freq == 0, 0))
/* Something went wrong. */
break;
}

if (clock_id != CLOCK_PROCESS_CPUTIME_ID
&& __pthread_clock_gettime != NULL)
{
retval = __pthread_clock_gettime (clock_id, freq, tp);
break;
}

/* Get the current counter. */
HP_TIMING_NOW (tsc);

/* Compute the offset since the start time of the process. */
tsc -= GL(dl_cpuclock_offset);

/* Compute the seconds. */
tp->tv_sec = tsc / freq;

/* And the nanoseconds. This computation should be stable until
we get machines with about 16GHz frequency. */
tp->tv_nsec = ((tsc % freq) * UINT64_C (1000000000)) / freq;

retval = 0;
}
break;
retval = hp_timing_gettime (clock_id, tp);
break;
#endif
}

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