commit: e05b2efb82596905ebfe88e8612ee81dec9b6592 From: john stultz <[email protected]> Date: Wed, 4 May 2011 18:16:50 -0700 Subject: [PATCH] clocksource: Install completely before selecting
Christian Hoffmann reported that the command line clocksource override with acpi_pm timer fails: Kernel command line: <SNIP> clocksource=acpi_pm hpet clockevent registered Switching to clocksource hpet Override clocksource acpi_pm is not HRT compatible. Cannot switch while in HRT/NOHZ mode. The watchdog code is what enables CLOCK_SOURCE_VALID_FOR_HRES, but we actually end up selecting the clocksource before we enqueue it into the watchdog list, so that's why we see the warning and fail to switch to acpi_pm timer as requested. That's particularly bad when we want to debug timekeeping related problems in early boot. Put the selection call last. Reported-by: Christian Hoffmann <[email protected]> Signed-off-by: John Stultz <[email protected]> Cc: [email protected] # 32... Link: http://lkml.kernel.org/r/%3C1304558210.2943.24.camel%40work-vm%3E Signed-off-by: Thomas Gleixner <[email protected]> --- kernel/time/clocksource.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 6519cf6..0e17c10 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -685,8 +685,8 @@ int __clocksource_register_scale(struct clocksource *cs, u32 scale, u32 freq) /* Add clocksource to the clcoksource list */ mutex_lock(&clocksource_mutex); clocksource_enqueue(cs); - clocksource_select(); clocksource_enqueue_watchdog(cs); + clocksource_select(); mutex_unlock(&clocksource_mutex); return 0; } @@ -706,8 +706,8 @@ int clocksource_register(struct clocksource *cs) mutex_lock(&clocksource_mutex); clocksource_enqueue(cs); - clocksource_select(); clocksource_enqueue_watchdog(cs); + clocksource_select(); mutex_unlock(&clocksource_mutex); return 0; } _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
