From 5a90cf205c922707ffed2d8f87cefd942e96b0ba Mon Sep 17 00:00:00 2001 From: john stultz Date: Wed, 2 May 2007 19:27:08 +0200 Subject: [PATCH] x86: Log reason why TSC was marked unstable Change mark_tsc_unstable() so it takes a string argument, which holds the reason the TSC was marked unstable. This is then displayed the first time mark_tsc_unstable is called. This should help us better debug why the TSC was marked unstable on certain systems and allow us to make sure we're not being overly paranoid when throwing out this troublesome clocksource. Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Andi Kleen --- arch/x86_64/kernel/tsc.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'arch/x86_64/kernel/tsc.c') diff --git a/arch/x86_64/kernel/tsc.c b/arch/x86_64/kernel/tsc.c index 5c84992c676..48f9a8e6aa9 100644 --- a/arch/x86_64/kernel/tsc.c +++ b/arch/x86_64/kernel/tsc.c @@ -111,7 +111,7 @@ static int time_cpufreq_notifier(struct notifier_block *nb, unsigned long val, tsc_khz = cpufreq_scale(tsc_khz_ref, ref_freq, freq->new); if (!(freq->flags & CPUFREQ_CONST_LOOPS)) - mark_tsc_unstable(); + mark_tsc_unstable("cpufreq changes"); } set_cyc2ns_scale(tsc_khz_ref); @@ -199,10 +199,11 @@ static struct clocksource clocksource_tsc = { .vread = vread_tsc, }; -void mark_tsc_unstable(void) +void mark_tsc_unstable(char *reason) { if (!tsc_unstable) { tsc_unstable = 1; + printk("Marking TSC unstable due to %s\n", reason); /* Change only the rating, when not registered */ if (clocksource_tsc.mult) clocksource_change_rating(&clocksource_tsc, 0); -- cgit v1.2.3-18-g5258