2007-06-13 06:07:26

by Tony Breeds

[permalink] [raw]
Subject: [PATCH] Add per clocksource hook to settimeofday().

I'm working on a clocksource implementation for all powerpc platforms.
some of these platforms needs to do a little work as part of the
settimeofday() syscall and I can't see a way to do that without adding
this hook to clocksource.

From: Tony Breeds <[email protected]>

Add per clocksource hook to settimeofday().

Some clocksources need to do extra work as part of the settimeofday call, this
hook make it easy to do so.

Signed-off-by: Tony Breeds <[email protected]>

---

include/linux/clocksource.h | 3 +++
kernel/time/timekeeping.c | 3 +++
2 files changed, 6 insertions(+)

Index: working/include/linux/clocksource.h
===================================================================
--- working.orig/include/linux/clocksource.h
+++ working/include/linux/clocksource.h
@@ -50,6 +50,7 @@ struct clocksource;
* @flags: flags describing special properties
* @vread: vsyscall based read
* @resume: resume function for the clocksource, if necessary
+ * @settimeofday: [Optional] Do arch specific work during do_settimeofday
* @cycle_interval: Used internally by timekeeping core, please ignore.
* @xtime_interval: Used internally by timekeeping core, please ignore.
*/
@@ -68,6 +69,8 @@ struct clocksource {
cycle_t (*vread)(void);
void (*resume)(void);

+ void (*settimeofday)(struct clocksource *cs, struct timespec *ts);
+
/* timekeeping specific data, ignore */
cycle_t cycle_interval;
u64 xtime_interval;
Index: working/kernel/time/timekeeping.c
===================================================================
--- working.orig/kernel/time/timekeeping.c
+++ working/kernel/time/timekeeping.c
@@ -151,6 +151,9 @@ int do_settimeofday(struct timespec *tv)
clock->error = 0;
ntp_clear();

+ if (clock->settimeofday)
+ clock->settimeofday(clock, tv);
+
update_vsyscall(&xtime, clock);

write_sequnlock_irqrestore(&xtime_lock, flags);

Yours Tony

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