diff options
| author | john stultz <johnstul@us.ibm.com> | 2007-07-25 03:38:34 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-07-25 19:17:44 +0200 |
| commit | 17c38b7490b3f0300c7812aefdae2ddda7ab4112 (patch) | |
| tree | 0f7a9ee0c691aef3497030e38c3ba8e3c13a985c /kernel/hrtimer.c | |
| parent | Cleanup non-arch xtime uses, use get_seconds() or current_kernel_time(). (diff) | |
| download | linux-17c38b7490b3f0300c7812aefdae2ddda7ab4112.tar.xz linux-17c38b7490b3f0300c7812aefdae2ddda7ab4112.zip | |
Cache xtime every call to update_wall_time
This avoids xtime lag seen with dynticks, because while 'xtime' itself
is still not updated often, we keep a 'xtime_cache' variable around that
contains the approximate real-time that _is_ updated each time we do a
'update_wall_time()', and is thus never off by more than one tick.
IOW, this restores the original semantics for 'xtime' users, as long as
you use the proper abstraction functions (ie 'current_kernel_time()' or
'get_seconds()' depending on whether you want a timespec or just the
seconds field).
[ Updated Patch. As penance for my sins I've also yanked another #ifdef
that was added to avoid the xtime lag w/ hrtimers. ]
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/hrtimer.c')
| -rw-r--r-- | kernel/hrtimer.c | 4 |
1 files changed, 0 insertions, 4 deletions
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index a7bb05e6cb63..c21ca6bfaa66 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -141,11 +141,7 @@ static void hrtimer_get_softirq_time(struct hrtimer_cpu_base *base) do { seq = read_seqbegin(&xtime_lock); -#ifdef CONFIG_NO_HZ - getnstimeofday(&xts); -#else xts = current_kernel_time(); -#endif tom = wall_to_monotonic; } while (read_seqretry(&xtime_lock, seq)); |