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Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

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Pull timer core updates from Thomas Gleixner.

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ia64: vsyscall: Add missing paranthesis
  alarmtimer: Don't call rtc_timer_init() when CONFIG_RTC_CLASS=n
  x86: vdso: Put declaration before code
  x86-64: Inline vdso clock_gettime helpers
  x86-64: Simplify and optimize vdso clock_gettime monotonic variants
  kernel-time: fix s/then/than/ spelling errors
  time: remove no_sync_cmos_clock
  time: Avoid scary backtraces when warning of > 11% adj
  alarmtimer: Make sure we initialize the rtctimer
  ntp: Fix leap-second hrtimer livelock
  x86, tsc: Skip refined tsc calibration on systems with reliable TSC
  rtc: Provide flag for rtc devices that don't support UIE
  ia64: vsyscall: Use seqcount instead of seqlock
  x86: vdso: Use seqcount instead of seqlock
  x86: vdso: Remove bogus locking in update_vsyscall_tz()
  time: Remove bogus comments
  time: Fix change_clocksource locking
  time: x86: Fix race switching from vsyscall to non-vsyscall clock
This commit is contained in:
Linus Torvalds
2012-03-29 14:16:48 -07:00
parent 93f378883c 646783a389
commit bcd550745f
18 changed files with 203 additions and 236 deletions
Download Patch File Download Diff File Expand all files Collapse all files
arch/x86/vdso/vclock_gettime.c
+67 -68
View File
@@ -70,100 +70,98 @@ notrace static long vdso_fallback_gettime(long clock, struct timespec *ts)
return ret;
}
notrace static long vdso_fallback_gtod(struct timeval *tv, struct timezone *tz)
{
long ret;
asm("syscall" : "=a" (ret) :
"0" (__NR_gettimeofday), "D" (tv), "S" (tz) : "memory");
return ret;
}
notrace static inline long vgetns(void)
{
long v;
cycles_t cycles;
if (gtod->clock.vclock_mode == VCLOCK_TSC)
cycles = vread_tsc();
else
else if (gtod->clock.vclock_mode == VCLOCK_HPET)
cycles = vread_hpet();
else
return 0;
v = (cycles - gtod->clock.cycle_last) & gtod->clock.mask;
return (v * gtod->clock.mult) >> gtod->clock.shift;
}
notrace static noinline int do_realtime(struct timespec *ts)
/* Code size doesn't matter (vdso is 4k anyway) and this is faster. */
notrace static int __always_inline do_realtime(struct timespec *ts)
{
unsigned long seq, ns;
int mode;
do {
seq = read_seqbegin(&gtod->lock);
seq = read_seqcount_begin(&gtod->seq);
mode = gtod->clock.vclock_mode;
ts->tv_sec = gtod->wall_time_sec;
ts->tv_nsec = gtod->wall_time_nsec;
ns = vgetns();
} while (unlikely(read_seqretry(&gtod->lock, seq)));
} while (unlikely(read_seqcount_retry(&gtod->seq, seq)));
timespec_add_ns(ts, ns);
return 0;
return mode;
}
notrace static noinline int do_monotonic(struct timespec *ts)
notrace static int do_monotonic(struct timespec *ts)
{
unsigned long seq, ns, secs;
unsigned long seq, ns;
int mode;
do {
seq = read_seqbegin(&gtod->lock);
secs = gtod->wall_time_sec;
ns = gtod->wall_time_nsec + vgetns();
secs += gtod->wall_to_monotonic.tv_sec;
ns += gtod->wall_to_monotonic.tv_nsec;
} while (unlikely(read_seqretry(&gtod->lock, seq)));
seq = read_seqcount_begin(&gtod->seq);
mode = gtod->clock.vclock_mode;
ts->tv_sec = gtod->monotonic_time_sec;
ts->tv_nsec = gtod->monotonic_time_nsec;
ns = vgetns();
} while (unlikely(read_seqcount_retry(&gtod->seq, seq)));
timespec_add_ns(ts, ns);
/* wall_time_nsec, vgetns(), and wall_to_monotonic.tv_nsec
* are all guaranteed to be nonnegative.
*/
while (ns >= NSEC_PER_SEC) {
ns -= NSEC_PER_SEC;
++secs;
}
ts->tv_sec = secs;
ts->tv_nsec = ns;
return 0;
return mode;
}
notrace static noinline int do_realtime_coarse(struct timespec *ts)
notrace static int do_realtime_coarse(struct timespec *ts)
{
unsigned long seq;
do {
seq = read_seqbegin(&gtod->lock);
seq = read_seqcount_begin(&gtod->seq);
ts->tv_sec = gtod->wall_time_coarse.tv_sec;
ts->tv_nsec = gtod->wall_time_coarse.tv_nsec;
} while (unlikely(read_seqretry(&gtod->lock, seq)));
} while (unlikely(read_seqcount_retry(&gtod->seq, seq)));
return 0;
}
notrace static noinline int do_monotonic_coarse(struct timespec *ts)
notrace static int do_monotonic_coarse(struct timespec *ts)
{
unsigned long seq, ns, secs;
unsigned long seq;
do {
seq = read_seqbegin(&gtod->lock);
secs = gtod->wall_time_coarse.tv_sec;
ns = gtod->wall_time_coarse.tv_nsec;
secs += gtod->wall_to_monotonic.tv_sec;
ns += gtod->wall_to_monotonic.tv_nsec;
} while (unlikely(read_seqretry(&gtod->lock, seq)));
/* wall_time_nsec and wall_to_monotonic.tv_nsec are
* guaranteed to be between 0 and NSEC_PER_SEC.
*/
if (ns >= NSEC_PER_SEC) {
ns -= NSEC_PER_SEC;
++secs;
}
ts->tv_sec = secs;
ts->tv_nsec = ns;
seq = read_seqcount_begin(&gtod->seq);
ts->tv_sec = gtod->monotonic_time_coarse.tv_sec;
ts->tv_nsec = gtod->monotonic_time_coarse.tv_nsec;
} while (unlikely(read_seqcount_retry(&gtod->seq, seq)));
return 0;
}
notrace int __vdso_clock_gettime(clockid_t clock, struct timespec *ts)
{
int ret = VCLOCK_NONE;
switch (clock) {
case CLOCK_REALTIME:
if (likely(gtod->clock.vclock_mode != VCLOCK_NONE))
return do_realtime(ts);
ret = do_realtime(ts);
break;
case CLOCK_MONOTONIC:
if (likely(gtod->clock.vclock_mode != VCLOCK_NONE))
return do_monotonic(ts);
ret = do_monotonic(ts);
break;
case CLOCK_REALTIME_COARSE:
return do_realtime_coarse(ts);
@@ -171,32 +169,33 @@ notrace int __vdso_clock_gettime(clockid_t clock, struct timespec *ts)
return do_monotonic_coarse(ts);
}
return vdso_fallback_gettime(clock, ts);
if (ret == VCLOCK_NONE)
return vdso_fallback_gettime(clock, ts);
return 0;
}
int clock_gettime(clockid_t, struct timespec *)
__attribute__((weak, alias("__vdso_clock_gettime")));
notrace int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz)
{
long ret;
if (likely(gtod->clock.vclock_mode != VCLOCK_NONE)) {
if (likely(tv != NULL)) {
BUILD_BUG_ON(offsetof(struct timeval, tv_usec) !=
offsetof(struct timespec, tv_nsec) ||
sizeof(*tv) != sizeof(struct timespec));
do_realtime((struct timespec *)tv);
tv->tv_usec /= 1000;
}
if (unlikely(tz != NULL)) {
/* Avoid memcpy. Some old compilers fail to inline it */
tz->tz_minuteswest = gtod->sys_tz.tz_minuteswest;
tz->tz_dsttime = gtod->sys_tz.tz_dsttime;
}
return 0;
long ret = VCLOCK_NONE;
if (likely(tv != NULL)) {
BUILD_BUG_ON(offsetof(struct timeval, tv_usec) !=
offsetof(struct timespec, tv_nsec) ||
sizeof(*tv) != sizeof(struct timespec));
ret = do_realtime((struct timespec *)tv);
tv->tv_usec /= 1000;
}
asm("syscall" : "=a" (ret) :
"0" (__NR_gettimeofday), "D" (tv), "S" (tz) : "memory");
return ret;
if (unlikely(tz != NULL)) {
/* Avoid memcpy. Some old compilers fail to inline it */
tz->tz_minuteswest = gtod->sys_tz.tz_minuteswest;
tz->tz_dsttime = gtod->sys_tz.tz_dsttime;
}
if (ret == VCLOCK_NONE)
return vdso_fallback_gtod(tv, tz);
return 0;
}
int gettimeofday(struct timeval *, struct timezone *)
__attribute__((weak, alias("__vdso_gettimeofday")));