Re: [PATCH 06/11] Add suspend\resume support for PV on HVM guests.

From: Jeremy Fitzhardinge
Date: Tue May 25 2010 - 16:20:26 EST


On 05/24/2010 11:27 AM, Stefano Stabellini wrote:
> Suspend\resume requires few different thing on HVM: the suspend
> hypercall is different, we don't need to save\restore any memory related
> setting, but we need to reinitialize the shared info page and the
> callback mechanism.
>
> Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>
> ---
> arch/x86/xen/enlighten.c | 14 +++++++++---
> arch/x86/xen/suspend.c | 6 +++++
> arch/x86/xen/xen-ops.h | 1 +
> drivers/xen/manage.c | 45 ++++++++++++++++++++++++++++++++++++++++---
> drivers/xen/platform-pci.c | 23 +++++++++++++++++++++-
> include/xen/xen-ops.h | 3 ++
> 6 files changed, 83 insertions(+), 9 deletions(-)
>
> diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
> index ed34b30..cb316b5 100644
> --- a/arch/x86/xen/enlighten.c
> +++ b/arch/x86/xen/enlighten.c
> @@ -1263,12 +1263,14 @@ static int init_hvm_pv_info(int *major, int *minor)
> return 0;
> }
>
> -static void __init init_shared_info(void)
> +void init_shared_info(void)
>

This needs a xen_ prefix.

J

> {
> + int cpu;
> struct xen_add_to_physmap xatp;
> - struct shared_info *shared_info_page;
> + static struct shared_info *shared_info_page = 0;
>
> - shared_info_page = (struct shared_info *) alloc_bootmem_pages(PAGE_SIZE);
> + if (!shared_info_page)
> + shared_info_page = (struct shared_info *) alloc_bootmem_pages(PAGE_SIZE);
> xatp.domid = DOMID_SELF;
> xatp.idx = 0;
> xatp.space = XENMAPSPACE_shared_info;
> @@ -1280,7 +1282,11 @@ static void __init init_shared_info(void)
>
> /* Don't do the full vcpu_info placement stuff until we have a
> possible map and a non-dummy shared_info. */
> - per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
> + /* init_shared_info is run at resume time too, in that case multiple
> + * vcpus might be online */
> + for_each_online_cpu(cpu) {
> + per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
> + }
> }
>
> static int __cpuinit xen_hvm_cpu_notify(struct notifier_block *self,
> diff --git a/arch/x86/xen/suspend.c b/arch/x86/xen/suspend.c
> index 987267f..ef517ee 100644
> --- a/arch/x86/xen/suspend.c
> +++ b/arch/x86/xen/suspend.c
> @@ -26,6 +26,12 @@ void xen_pre_suspend(void)
> BUG();
> }
>
> +void xen_hvm_post_suspend(int suspend_cancelled)
> +{
> + init_shared_info();
> + xen_callback_vector();
> +}
> +
> void xen_post_suspend(int suspend_cancelled)
> {
> xen_build_mfn_list_list();
> diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h
> index 0d0e0e6..caf89ee 100644
> --- a/arch/x86/xen/xen-ops.h
> +++ b/arch/x86/xen/xen-ops.h
> @@ -39,6 +39,7 @@ void xen_enable_syscall(void);
> void xen_vcpu_restore(void);
>
> void xen_callback_vector(void);
> +void init_shared_info(void);
>
> void __init xen_build_dynamic_phys_to_machine(void);
>
> diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c
> index 2ac4440..0716ba6 100644
> --- a/drivers/xen/manage.c
> +++ b/drivers/xen/manage.c
> @@ -9,6 +9,7 @@
> #include <linux/stop_machine.h>
> #include <linux/freezer.h>
>
> +#include <xen/xen.h>
> #include <xen/xenbus.h>
> #include <xen/grant_table.h>
> #include <xen/events.h>
> @@ -17,6 +18,7 @@
>
> #include <asm/xen/hypercall.h>
> #include <asm/xen/page.h>
> +#include <asm/xen/hypervisor.h>
>
> enum shutdown_state {
> SHUTDOWN_INVALID = -1,
> @@ -33,10 +35,30 @@ enum shutdown_state {
> static enum shutdown_state shutting_down = SHUTDOWN_INVALID;
>
> #ifdef CONFIG_PM_SLEEP
> -static int xen_suspend(void *data)
> +static int xen_hvm_suspend(void *data)
> {
> + struct sched_shutdown r = { .reason = SHUTDOWN_suspend };
> int *cancelled = data;
> +
> + BUG_ON(!irqs_disabled());
> +
> + *cancelled = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
> +
> + xen_hvm_post_suspend(*cancelled);
> + gnttab_resume();
> +
> + if (!*cancelled) {
> + xen_irq_resume();
> + xen_timer_resume();
> + }
> +
> + return 0;
> +}
> +
> +static int xen_suspend(void *data)
> +{
> int err;
> + int *cancelled = data;
>
> BUG_ON(!irqs_disabled());
>
> @@ -112,7 +134,10 @@ static void do_suspend(void)
> goto out_resume;
> }
>
> - err = stop_machine(xen_suspend, &cancelled, cpumask_of(0));
> + if (xen_hvm_domain())
> + err = stop_machine(xen_hvm_suspend, &cancelled, cpumask_of(0));
> + else
> + err = stop_machine(xen_suspend, &cancelled, cpumask_of(0));
>
> dpm_resume_noirq(PMSG_RESUME);
>
> @@ -261,7 +286,19 @@ static int shutdown_event(struct notifier_block *notifier,
> return NOTIFY_DONE;
> }
>
> -static int __init setup_shutdown_event(void)
> +static int __init __setup_shutdown_event(void)
> +{
> + /* Delay initialization in the PV on HVM case */
> + if (xen_hvm_domain())
> + return 0;
> +
> + if (!xen_pv_domain())
> + return -ENODEV;
> +
> + return xen_setup_shutdown_event();
> +}
> +
> +int xen_setup_shutdown_event(void)
> {
> static struct notifier_block xenstore_notifier = {
> .notifier_call = shutdown_event
> @@ -271,4 +308,4 @@ static int __init setup_shutdown_event(void)
> return 0;
> }
>
> -subsys_initcall(setup_shutdown_event);
> +subsys_initcall(__setup_shutdown_event);
> diff --git a/drivers/xen/platform-pci.c b/drivers/xen/platform-pci.c
> index 0f78318..70395c9 100644
> --- a/drivers/xen/platform-pci.c
> +++ b/drivers/xen/platform-pci.c
> @@ -31,6 +31,7 @@
> #include <xen/xenbus.h>
> #include <xen/events.h>
> #include <xen/hvm.h>
> +#include <xen/xen-ops.h>
>
> #define DRV_NAME "xen-platform-pci"
>
> @@ -41,6 +42,7 @@ MODULE_LICENSE("GPL");
> static unsigned long platform_mmio;
> static unsigned long platform_mmio_alloc;
> static unsigned long platform_mmiolen;
> +static uint64_t callback_via;
>
> unsigned long alloc_xen_mmio(unsigned long len)
> {
> @@ -85,13 +87,25 @@ static int xen_allocate_irq(struct pci_dev *pdev)
> "xen-platform-pci", pdev);
> }
>
> +static int platform_pci_resume(struct pci_dev *pdev)
> +{
> + int err;
> + if (xen_have_vector_callback)
> + return 0;
> + err = xen_set_callback_via(callback_via);
> + if (err) {
> + printk("platform_pci_resume failure!\n");
> + return err;
> + }
> + return 0;
> +}
> +
> static int __devinit platform_pci_init(struct pci_dev *pdev,
> const struct pci_device_id *ent)
> {
> int i, ret;
> long ioaddr, iolen;
> long mmio_addr, mmio_len;
> - uint64_t callback_via;
>
> i = pci_enable_device(pdev);
> if (i)
> @@ -145,6 +159,10 @@ static int __devinit platform_pci_init(struct pci_dev *pdev,
> ret = xenbus_probe_init();
> if (ret)
> goto out;
> + ret = xen_setup_shutdown_event();
> + if (ret)
> + goto out;
> +
>
> out:
> if (ret) {
> @@ -168,6 +186,9 @@ static struct pci_driver platform_driver = {
> .name = DRV_NAME,
> .probe = platform_pci_init,
> .id_table = platform_pci_tbl,
> +#ifdef CONFIG_PM
> + .resume_early = platform_pci_resume,
> +#endif
> };
>
> static int __init platform_pci_module_init(void)
> diff --git a/include/xen/xen-ops.h b/include/xen/xen-ops.h
> index 883a21b..46bc81e 100644
> --- a/include/xen/xen-ops.h
> +++ b/include/xen/xen-ops.h
> @@ -7,6 +7,7 @@ DECLARE_PER_CPU(struct vcpu_info *, xen_vcpu);
>
> void xen_pre_suspend(void);
> void xen_post_suspend(int suspend_cancelled);
> +void xen_hvm_post_suspend(int suspend_cancelled);
>
> void xen_mm_pin_all(void);
> void xen_mm_unpin_all(void);
> @@ -14,4 +15,6 @@ void xen_mm_unpin_all(void);
> void xen_timer_resume(void);
> void xen_arch_resume(void);
>
> +int xen_setup_shutdown_event(void);
> +
> #endif /* INCLUDE_XEN_OPS_H */
>

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