diff options
author | K. Y. Srinivasan <kys@microsoft.com> | 2015-08-05 10:52:42 +0300 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-08-05 21:44:29 +0300 |
commit | ca9357bd26c2f8e7b909321eedd651f52cc30d04 (patch) | |
tree | f9417defaed1252c6bc0442285314ee9ca777258 /arch | |
parent | bc609cb47fb2e74654e23cef0a1d4db38b6570a3 (diff) | |
download | linux-ca9357bd26c2f8e7b909321eedd651f52cc30d04.tar.xz |
Drivers: hv: vmbus: Implement a clocksource based on the TSC page
The current Hyper-V clock source is based on the per-partition reference counter
and this counter is being accessed via s synthetic MSR - HV_X64_MSR_TIME_REF_COUNT.
Hyper-V has a more efficient way of computing the per-partition reference
counter value that does not involve reading a synthetic MSR. We implement
a time source based on this mechanism.
Tested-by: Vivek Yadav <vyadav@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/x86/include/uapi/asm/hyperv.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/x86/include/uapi/asm/hyperv.h b/arch/x86/include/uapi/asm/hyperv.h index f36d56bd7632..f0412c50c47b 100644 --- a/arch/x86/include/uapi/asm/hyperv.h +++ b/arch/x86/include/uapi/asm/hyperv.h @@ -27,6 +27,8 @@ #define HV_X64_MSR_VP_RUNTIME_AVAILABLE (1 << 0) /* Partition Reference Counter (HV_X64_MSR_TIME_REF_COUNT) available*/ #define HV_X64_MSR_TIME_REF_COUNT_AVAILABLE (1 << 1) +/* Partition reference TSC MSR is available */ +#define HV_X64_MSR_REFERENCE_TSC_AVAILABLE (1 << 9) /* A partition's reference time stamp counter (TSC) page */ #define HV_X64_MSR_REFERENCE_TSC 0x40000021 |