clocksource/drivers/hyperv: Add Hyper-V specific sched clock function
Hyper-V guests use the default native_sched_clock() in pv_ops.time.sched_clock on x86. But native_sched_clock() directly uses the raw TSC value, which can be discontinuous in a Hyper-V VM. Add the generic hv_setup_sched_clock() to set the sched clock function appropriately. On x86, this sets pv_ops.time.sched_clock to read the Hyper-V reference TSC value that is scaled and adjusted to be continuous. Also move the Hyper-V reference TSC initialization much earlier in the boot process so no discontinuity is observed when pv_ops.time.sched_clock calculates its offset. [ tglx: Folded build fix ] Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lkml.kernel.org/r/20190814123216.32245-3-Tianyu.Lan@microsoft.com
This commit is contained in:

committed by
Thomas Gleixner

parent
adb87ff4f9
commit
bd00cd52d5
@@ -167,6 +167,7 @@ void hyperv_report_panic(struct pt_regs *regs, long err);
|
||||
void hyperv_report_panic_msg(phys_addr_t pa, size_t size);
|
||||
bool hv_is_hyperv_initialized(void);
|
||||
void hyperv_cleanup(void);
|
||||
void hv_setup_sched_clock(void *sched_clock);
|
||||
#else /* CONFIG_HYPERV */
|
||||
static inline bool hv_is_hyperv_initialized(void) { return false; }
|
||||
static inline void hyperv_cleanup(void) {}
|
||||
|
Reference in New Issue
Block a user