From: Thomas Gleixner <tglx@linutronix.de>
Date: Wed, 28 Jul 2010 19:49:22 +0000 (+0200)
Subject: Merge branch 'powerpc.cherry-picks' into timers/clocksource
X-Git-Url: https://rtime.felk.cvut.cz/gitweb/lisovros/linux_canprio.git/commitdiff_plain/47916be4e28c3d6fdb97dd8fb887d1d9b3145b9d

Merge branch 'powerpc.cherry-picks' into timers/clocksource

Conflicts:
	arch/powerpc/kernel/time.c

Reason: The powerpc next tree contains two commits which conflict with
the timekeeping changes:

8fd63a9e powerpc: Rework VDSO gettimeofday to prevent time going backwards
c1aa687d powerpc: Clean up obsolete code relating to decrementer and timebase

John Stultz identified them and provided the conflict resolution.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---

47916be4e28c3d6fdb97dd8fb887d1d9b3145b9d
diff --cc arch/powerpc/kernel/time.c
index e215f76bba1,ccb8759c853..ce53dfa7130
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@@ -849,25 -796,10 +796,30 @@@ static cycle_t timebase_read(struct clo
  	return (cycle_t)get_tb();
  }
  
 -static inline void update_gtod(u64 new_tb_stamp, u64 new_stamp_xsec,
 -			       u64 new_tb_to_xs, struct timespec *now,
 -			       u32 frac_sec)
 +void update_vsyscall(struct timespec *wall_time, struct timespec *wtm,
 +			struct clocksource *clock, u32 mult)
  {
 +	u64 new_tb_to_xs, new_stamp_xsec;
++	u32 frac_sec;
 +
 +	if (clock != &clocksource_timebase)
 +		return;
 +
 +	/* Make userspace gettimeofday spin until we're done. */
 +	++vdso_data->tb_update_count;
 +	smp_mb();
 +
 +	/* XXX this assumes clock->shift == 22 */
 +	/* 4611686018 ~= 2^(20+64-22) / 1e9 */
 +	new_tb_to_xs = (u64) mult * 4611686018ULL;
 +	new_stamp_xsec = (u64) wall_time->tv_nsec * XSEC_PER_SEC;
 +	do_div(new_stamp_xsec, 1000000000);
 +	new_stamp_xsec += (u64) wall_time->tv_sec * XSEC_PER_SEC;
 +
++	BUG_ON(wall_time->tv_nsec >= NSEC_PER_SEC);
++	/* this is tv_nsec / 1e9 as a 0.32 fraction */
++	frac_sec = ((u64) wall_time->tv_nsec * 18446744073ULL) >> 32;
++
  	/*
  	 * tb_update_count is used to allow the userspace gettimeofday code
  	 * to assure itself that it sees a consistent view of the tb_to_xs and
@@@ -879,12 -811,13 +831,13 @@@
  	 * We expect the caller to have done the first increment of
  	 * vdso_data->tb_update_count already.
  	 */
 -	vdso_data->tb_orig_stamp = new_tb_stamp;
 +	vdso_data->tb_orig_stamp = clock->cycle_last;
  	vdso_data->stamp_xsec = new_stamp_xsec;
  	vdso_data->tb_to_xs = new_tb_to_xs;
 -	vdso_data->wtom_clock_sec = wall_to_monotonic.tv_sec;
 -	vdso_data->wtom_clock_nsec = wall_to_monotonic.tv_nsec;
 -	vdso_data->stamp_xtime = *now;
 +	vdso_data->wtom_clock_sec = wtm->tv_sec;
 +	vdso_data->wtom_clock_nsec = wtm->tv_nsec;
 +	vdso_data->stamp_xtime = *wall_time;
+ 	vdso_data->stamp_sec_fraction = frac_sec;
  	smp_wmb();
  	++(vdso_data->tb_update_count);
  }