[PATCH] fix and optimize clock source update
This fixes the clock source updates in update_wall_time() to correctly
track the time coming in via current_tick_length(). Optimize the fast
paths to be as short as possible to keep the overhead low.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Acked-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 742f07a..7dd5dab 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -102,7 +102,7 @@
u64 tb_to_xs;
unsigned tb_to_us;
-#define TICKLEN_SCALE (SHIFT_SCALE - 10)
+#define TICKLEN_SCALE TICK_LENGTH_SHIFT
u64 last_tick_len; /* units are ns / 2^TICKLEN_SCALE */
u64 ticklen_to_xs; /* 0.64 fraction */
@@ -534,7 +534,7 @@
if (__USE_RTC())
return;
- tlen = current_tick_length(SHIFT_SCALE - 10);
+ tlen = current_tick_length();
offset = cur_tb - do_gtod.varp->tb_orig_stamp;
if (tlen == last_tick_len && offset < 0x80000000u)
return;