x86/hyperv: Implement hv_get_tsc_page()

To use Hyper-V TSC page clocksource from vDSO we need to make tsc_pg
available. Implement hv_get_tsc_page() and add CONFIG_HYPERV_TSCPAGE to
make #ifdef-s simple.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: devel@linuxdriverproject.org
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: virtualization@lists.linux-foundation.org
Link: http://lkml.kernel.org/r/20170303132142.25595-2-vkuznets@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Vitaly Kuznetsov 2017-03-03 14:21:40 +01:00 committed by Thomas Gleixner
parent 434fd6353b
commit bd2a9adaad
3 changed files with 18 additions and 2 deletions

View File

@ -27,10 +27,15 @@
#include <linux/clockchips.h>
#ifdef CONFIG_X86_64
#ifdef CONFIG_HYPERV_TSCPAGE
static struct ms_hyperv_tsc_page *tsc_pg;
struct ms_hyperv_tsc_page *hv_get_tsc_page(void)
{
return tsc_pg;
}
static u64 read_hv_clock_tsc(struct clocksource *arg)
{
u64 current_tick;
@ -139,7 +144,7 @@ void hyperv_init(void)
/*
* Register Hyper-V specific clocksource.
*/
#ifdef CONFIG_X86_64
#ifdef CONFIG_HYPERV_TSCPAGE
if (ms_hyperv.features & HV_X64_MSR_REFERENCE_TSC_AVAILABLE) {
union hv_x64_msr_hypercall_contents tsc_msr;

View File

@ -176,4 +176,12 @@ void hyperv_report_panic(struct pt_regs *regs);
bool hv_is_hypercall_page_setup(void);
void hyperv_cleanup(void);
#endif
#ifdef CONFIG_HYPERV_TSCPAGE
struct ms_hyperv_tsc_page *hv_get_tsc_page(void);
#else
static inline struct ms_hyperv_tsc_page *hv_get_tsc_page(void)
{
return NULL;
}
#endif
#endif

View File

@ -7,6 +7,9 @@ config HYPERV
Select this option to run Linux as a Hyper-V client operating
system.
config HYPERV_TSCPAGE
def_bool HYPERV && X86_64
config HYPERV_UTILS
tristate "Microsoft Hyper-V Utilities driver"
depends on HYPERV && CONNECTOR && NLS