diff options
Diffstat (limited to 'arch/x86_64/kernel/apic.c')
| -rw-r--r-- | arch/x86_64/kernel/apic.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/arch/x86_64/kernel/apic.c b/arch/x86_64/kernel/apic.c index e5b14c57eaa0..d70605eda333 100644 --- a/arch/x86_64/kernel/apic.c +++ b/arch/x86_64/kernel/apic.c @@ -962,12 +962,14 @@ void smp_apic_timer_interrupt(struct pt_regs *regs) irq_exit(); } +int __initdata unsync_tsc_on_multicluster; + /* * oem_force_hpet_timer -- force HPET mode for some boxes. * * Thus far, the major user of this is IBM's Summit2 series: * - * Clustered boxes may have unsynced TSC problems if they are + * Some clustered boxes may have unsynced TSC problems if they are * multi-chassis. Use available data to take a good guess. * If in doubt, go HPET. */ @@ -977,6 +979,11 @@ __cpuinit int oem_force_hpet_timer(void) unsigned id; DECLARE_BITMAP(clustermap, NUM_APIC_CLUSTERS); + /* Only do this check on IBM machines - big Unisys systems + use multiple clusters too, but have synchronized TSC */ + if (!unsync_tsc_on_multicluster) + return 0; + bitmap_zero(clustermap, NUM_APIC_CLUSTERS); for (i = 0; i < NR_CPUS; i++) { |