diff options
| author | Vitaly Kuznetsov <vkuznets@redhat.com> | 2017-02-04 19:57:13 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-02-10 17:40:19 +0300 |
| commit | dee863b571b0a76e9c549ee99e8782bb4bc6502b (patch) | |
| tree | c3f69821e106090e79c5a3c7e030616d72cfacd5 /arch/x86/hyperv | |
| parent | 9b06e1018abc65585b07c75c5b3f406dbabe7005 (diff) | |
| download | linux-dee863b571b0a76e9c549ee99e8782bb4bc6502b.tar.xz | |
hv: export current Hyper-V clocksource
As a preparation to implementing Hyper-V PTP device supporting
.getcrosststamp we need to export a reference to the current Hyper-V
clocksource in use (MSR or TSC page).
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86/hyperv')
| -rw-r--r-- | arch/x86/hyperv/hv_init.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c index b371d0e984a9..c224b7df4d21 100644 --- a/arch/x86/hyperv/hv_init.c +++ b/arch/x86/hyperv/hv_init.c @@ -99,6 +99,9 @@ static struct clocksource hyperv_cs_msr = { }; static void *hypercall_pg; +struct clocksource *hyperv_cs; +EXPORT_SYMBOL_GPL(hyperv_cs); + /* * This function is to be invoked early in the boot sequence after the * hypervisor has been detected. @@ -141,10 +144,10 @@ void hyperv_init(void) union hv_x64_msr_hypercall_contents tsc_msr; tsc_pg = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL); - if (!tsc_pg) { - clocksource_register_hz(&hyperv_cs_msr, NSEC_PER_SEC/100); - return; - } + if (!tsc_pg) + goto register_msr_cs; + + hyperv_cs = &hyperv_cs_tsc; rdmsrl(HV_X64_MSR_REFERENCE_TSC, tsc_msr.as_uint64); @@ -161,6 +164,8 @@ void hyperv_init(void) * the partition counter. */ +register_msr_cs: + hyperv_cs = &hyperv_cs_msr; if (ms_hyperv.features & HV_X64_MSR_TIME_REF_COUNT_AVAILABLE) clocksource_register_hz(&hyperv_cs_msr, NSEC_PER_SEC/100); } |