On 14/08/2019 14:32, lantianyu1986@xxxxxxxxx wrote:
> From: Tianyu Lan <Tianyu.Lan@xxxxxxxxxxxxx>
>
> Prepare to add Hyper-V sched clock callback and move Hyper-V
> Reference TSC initialization much earlier in the boot process. Earlier
> initialization is needed so that it happens while the timestamp value
> is still 0 and no discontinuity in the timestamp will occur when
> pv_ops.time.sched_clock calculates its offset. The earlier
> initialization requires that the Hyper-V TSC page be allocated
> statically instead of with vmalloc(), so fixup the references
> to the TSC page and the method of getting its physical address.
>
> Signed-off-by: Tianyu Lan <Tianyu.Lan@xxxxxxxxxxxxx>
Acked-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
> ---
> Change since v1:
> - Update commit log
> - Remove and operation of tsc page's va with PAGE_MASK
>
> arch/x86/entry/vdso/vma.c | 2 +-
> drivers/clocksource/hyperv_timer.c | 12 ++++--------
> 2 files changed, 5 insertions(+), 9 deletions(-)
>
> diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
> index 349a61d8bf34..f5937742b290 100644
> --- a/arch/x86/entry/vdso/vma.c
> +++ b/arch/x86/entry/vdso/vma.c
> @@ -122,7 +122,7 @@ static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
>
> if (tsc_pg && vclock_was_used(VCLOCK_HVCLOCK))
> return vmf_insert_pfn(vma, vmf->address,
> - vmalloc_to_pfn(tsc_pg));
> + virt_to_phys(tsc_pg) >> PAGE_SHIFT);
> }
>
> return VM_FAULT_SIGBUS;
> diff --git a/drivers/clocksource/hyperv_timer.c b/drivers/clocksource/hyperv_timer.c
> index ba2c79e6a0ee..432aa331df04 100644
> --- a/drivers/clocksource/hyperv_timer.c
> +++ b/drivers/clocksource/hyperv_timer.c
> @@ -214,17 +214,17 @@ EXPORT_SYMBOL_GPL(hyperv_cs);
>
> #ifdef CONFIG_HYPERV_TSCPAGE
>
> -static struct ms_hyperv_tsc_page *tsc_pg;
> +static struct ms_hyperv_tsc_page tsc_pg __aligned(PAGE_SIZE);
>
> struct ms_hyperv_tsc_page *hv_get_tsc_page(void)
> {
> - return tsc_pg;
> + return &tsc_pg;
> }
> EXPORT_SYMBOL_GPL(hv_get_tsc_page);
>
> static u64 notrace read_hv_sched_clock_tsc(void)
> {
> - u64 current_tick = hv_read_tsc_page(tsc_pg);
> + u64 current_tick = hv_read_tsc_page(&tsc_pg);
>
> if (current_tick == U64_MAX)
> hv_get_time_ref_count(current_tick);
> @@ -280,12 +280,8 @@ static bool __init hv_init_tsc_clocksource(void)
> if (!(ms_hyperv.features & HV_MSR_REFERENCE_TSC_AVAILABLE))
> return false;
>
> - tsc_pg = vmalloc(PAGE_SIZE);
> - if (!tsc_pg)
> - return false;
> -
> hyperv_cs = &hyperv_cs_tsc;
> - phys_addr = page_to_phys(vmalloc_to_page(tsc_pg));
> + phys_addr = virt_to_phys(&tsc_pg);
>
> /*
> * The Hyper-V TLFS specifies to preserve the value of reserved
>
--
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