Introduce boot based time

The commits

  411187fb05cd11676b0979d9fbf3291db69dbce2 (GTOD: persistent clock support)
  c1d370e167d66b10bca3b602d3740405469383de (i386: use GTOD persistent clock
    support)

changed the monotonic time so that it no longer jumps after resume, but it's
not possible to use it for boot time and process start time calculations then.
 Also, the uptime no longer increases during suspend.

I add a variable to track the wall_to_monotonic changes, a function to get the
real boot time and a function to get the boot based time from the monotonic
one.

[akpm@linux-foundation.org: remove exports, add comment]
Signed-off-by: Tomas Janousek <tjanouse@redhat.com>
Cc: Tomas Smetana <tsmetana@redhat.com>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/time.h b/include/linux/time.h
index dda9be685ab6..4bb05a829be9 100644
--- a/include/linux/time.h
+++ b/include/linux/time.h
@@ -116,6 +116,8 @@ extern int do_setitimer(int which, struct itimerval *value,
 extern unsigned int alarm_setitimer(unsigned int seconds);
 extern int do_getitimer(int which, struct itimerval *value);
 extern void getnstimeofday(struct timespec *tv);
+extern void getboottime(struct timespec *ts);
+extern void monotonic_to_bootbased(struct timespec *ts);
 
 extern struct timespec timespec_trunc(struct timespec t, unsigned gran);
 extern int timekeeping_is_continuous(void);