lkml.org 
[lkml]   [2020]   [May]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH 09/12] x86/xen: save and restore steal clock
From
Date
On 5/19/20 7:28 PM, Anchal Agarwal wrote:
> From: Munehisa Kamata <kamatam@amazon.com>
>
> Save steal clock values of all present CPUs in the system core ops
> suspend callbacks. Also, restore a boot CPU's steal clock in the system
> core resume callback. For non-boot CPUs, restore after they're brought
> up, because runstate info for non-boot CPUs are not active until then.
>
> Signed-off-by: Munehisa Kamata <kamatam@amazon.com>
> Signed-off-by: Anchal Agarwal <anchalag@amazon.com>
> ---
> arch/x86/xen/suspend.c | 13 ++++++++++++-
> arch/x86/xen/time.c | 3 +++
> 2 files changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/xen/suspend.c b/arch/x86/xen/suspend.c
> index 784c4484100b..dae0f74f5390 100644
> --- a/arch/x86/xen/suspend.c
> +++ b/arch/x86/xen/suspend.c
> @@ -91,12 +91,20 @@ void xen_arch_suspend(void)
> static int xen_syscore_suspend(void)
> {
> struct xen_remove_from_physmap xrfp;
> - int ret;
> + int cpu, ret;
>
> /* Xen suspend does similar stuffs in its own logic */
> if (xen_suspend_mode_is_xen_suspend())
> return 0;
>
> + for_each_present_cpu(cpu) {
> + /*
> + * Nonboot CPUs are already offline, but the last copy of
> + * runstate info is still accessible.
> + */
> + xen_save_steal_clock(cpu);
> + }
> +
> xrfp.domid = DOMID_SELF;
> xrfp.gpfn = __pa(HYPERVISOR_shared_info) >> PAGE_SHIFT;
>
> @@ -118,6 +126,9 @@ static void xen_syscore_resume(void)
>
> pvclock_resume();


Doesn't make any difference but I think since this patch is where you
are dealing with clock then pvclock_resume() should be added here and
not in the earlier patch.


-boris


>
> + /* Nonboot CPUs will be resumed when they're brought up */
> + xen_restore_steal_clock(smp_processor_id());
> +
> gnttab_resume();
> }
>
> diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c
> index c8897aad13cd..33d754564b09 100644
> --- a/arch/x86/xen/time.c
> +++ b/arch/x86/xen/time.c
> @@ -545,6 +545,9 @@ static void xen_hvm_setup_cpu_clockevents(void)
> {
> int cpu = smp_processor_id();
> xen_setup_runstate_info(cpu);
> + if (cpu)
> + xen_restore_steal_clock(cpu);
> +
> /*
> * xen_setup_timer(cpu) - snprintf is bad in atomic context. Hence
> * doing it xen_hvm_cpu_notify (which gets called by smp_init during



\
 
 \ /
  Last update: 2020-05-31 01:47    [W:0.311 / U:2.700 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site