Messages in this thread Patch in this message | | | From | Peng Hao <> | Subject | [PATCH v2] kvmclock: fix nested guest always in tsc_early clocksource | Date | Sat, 14 Jul 2018 23:28:29 +0800 |
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In nested guest tsc_read_refs always return ULLONG_MAX, and that will call tsc_refine_calibration_work periodly. So nested guest will read acpi timer port 0x608 periodly.
The patch set X86_FEATURE_TSC_KNOWN_FREQ for kvmclock to avoid 'refine' operation.
Thanks for PeterZijlstra's advice.
Signed-off-by: Peng Hao <peng.hao2@zte.com.cn> --- arch/x86/kernel/kvmclock.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c index 8b26c9e..fc1562e 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -138,6 +138,7 @@ static unsigned long kvm_get_tsc_khz(void) src = &hv_clock[cpu].pvti; tsc_khz = pvclock_tsc_khz(src); put_cpu(); + setup_force_cpu_cap(X86_FEATURE_TSC_KNOWN_FREQ); return tsc_khz; } -- 1.8.3.1
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