From 82644459c592a28a3eab682f9b88d81019ddfe8b Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Sat, 21 Jul 2007 04:37:37 -0700 Subject: NTP: move the cmos update code into ntp.c i386 and sparc64 have the identical code to update the cmos clock. Move it into kernel/time/ntp.c as there are other architectures coming along with the same requirements. [akpm@linux-foundation.org: build fixes] Signed-off-by: Thomas Gleixner Cc: Chris Wright Cc: Ingo Molnar Cc: john stultz Cc: David Miller Cc: Roman Zippel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/time.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux/time.h') diff --git a/include/linux/time.h b/include/linux/time.h index ec3b0ced0afe..e6aea5146e5d 100644 --- a/include/linux/time.h +++ b/include/linux/time.h @@ -4,6 +4,7 @@ #include #ifdef __KERNEL__ +# include # include #endif @@ -94,6 +95,8 @@ extern struct timespec wall_to_monotonic; extern seqlock_t xtime_lock __attribute__((weak)); extern unsigned long read_persistent_clock(void); +extern int update_persistent_clock(struct timespec now); +extern int no_sync_cmos_clock __read_mostly; void timekeeping_init(void); static inline unsigned long get_seconds(void) -- cgit v1.2.3 From 2c6b47de17c75d553de3e2fb426d8298d2074585 Mon Sep 17 00:00:00 2001 From: john stultz Date: Tue, 24 Jul 2007 17:47:43 -0700 Subject: Cleanup non-arch xtime uses, use get_seconds() or current_kernel_time(). This avoids use of the kernel-internal "xtime" variable directly outside of the actual time-related functions. Instead, use the helper functions that we already have available to us. This doesn't actually change any behaviour, but this will allow us to fix the fact that "xtime" isn't updated very often with CONFIG_NO_HZ (because much of the realtime information is maintained as separate offsets to 'xtime'), which has caused interfaces that use xtime directly to get a time that is out of sync with the real-time clock by up to a third of a second or so. Signed-off-by: John Stultz Cc: Ingo Molnar Cc: Thomas Gleixner Signed-off-by: Linus Torvalds --- include/linux/time.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/time.h') diff --git a/include/linux/time.h b/include/linux/time.h index e6aea5146e5d..71181df8b744 100644 --- a/include/linux/time.h +++ b/include/linux/time.h @@ -107,7 +107,7 @@ static inline unsigned long get_seconds(void) struct timespec current_kernel_time(void); #define CURRENT_TIME (current_kernel_time()) -#define CURRENT_TIME_SEC ((struct timespec) { xtime.tv_sec, 0 }) +#define CURRENT_TIME_SEC ((struct timespec) { get_seconds(), 0 }) extern void do_gettimeofday(struct timeval *tv); extern int do_settimeofday(struct timespec *tv); -- cgit v1.2.3 From 17c38b7490b3f0300c7812aefdae2ddda7ab4112 Mon Sep 17 00:00:00 2001 From: john stultz Date: Tue, 24 Jul 2007 18:38:34 -0700 Subject: 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 Cc: Ingo Molnar Cc: Thomas Gleixner Signed-off-by: Linus Torvalds --- include/linux/time.h | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) (limited to 'include/linux/time.h') diff --git a/include/linux/time.h b/include/linux/time.h index 71181df8b744..6a5f503b4f1d 100644 --- a/include/linux/time.h +++ b/include/linux/time.h @@ -99,11 +99,7 @@ extern int update_persistent_clock(struct timespec now); extern int no_sync_cmos_clock __read_mostly; void timekeeping_init(void); -static inline unsigned long get_seconds(void) -{ - return xtime.tv_sec; -} - +unsigned long get_seconds(void); struct timespec current_kernel_time(void); #define CURRENT_TIME (current_kernel_time()) -- cgit v1.2.3