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context_tracking: KVM: Move guest enter/exit wrappers to KVM's domain

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Move the guest enter/exit wrappers to kvm_host.h so that KVM can manage
its context tracking vs. vtime accounting without bleeding too many KVM
details into the context tracking code.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210505002735.1684165-8-seanjc@google.com
This commit is contained in:
Sean Christopherson 2021-05-04 17:27:34 -07:00 committed by Thomas Gleixner
parent 14296e0c44
commit 1ca0016c14
2 changed files with 45 additions and 45 deletions
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45
include/linux/context_tracking.h
View File

@ -118,49 +118,4 @@ extern void context_tracking_init(void);
static inline void context_tracking_init(void) { }
#endif /* CONFIG_CONTEXT_TRACKING_FORCE */
/* must be called with irqs disabled */
static __always_inline void guest_enter_irqoff(void)
{
/*
* This is running in ioctl context so its safe to assume that it's the
* stime pending cputime to flush.
*/
instrumentation_begin();
vtime_account_guest_enter();
instrumentation_end();
/*
* KVM does not hold any references to rcu protected data when it
* switches CPU into a guest mode. In fact switching to a guest mode
* is very similar to exiting to userspace from rcu point of view. In
* addition CPU may stay in a guest mode for quite a long time (up to
* one time slice). Lets treat guest mode as quiescent state, just like
* we do with user-mode execution.
*/
if (!context_tracking_guest_enter()) {
instrumentation_begin();
rcu_virt_note_context_switch(smp_processor_id());
instrumentation_end();
}
}
static __always_inline void guest_exit_irqoff(void)
{
context_tracking_guest_exit();
instrumentation_begin();
/* Flush the guest cputime we spent on the guest */
vtime_account_guest_exit();
instrumentation_end();
}
static inline void guest_exit(void)
{
unsigned long flags;
local_irq_save(flags);
guest_exit_irqoff();
local_irq_restore(flags);
}
#endif

45
include/linux/kvm_host.h
View File

@ -338,6 +338,51 @@ struct kvm_vcpu {
struct kvm_dirty_ring dirty_ring;
};
/* must be called with irqs disabled */
static __always_inline void guest_enter_irqoff(void)
{
/*
* This is running in ioctl context so its safe to assume that it's the
* stime pending cputime to flush.
*/
instrumentation_begin();
vtime_account_guest_enter();
instrumentation_end();
/*
* KVM does not hold any references to rcu protected data when it
* switches CPU into a guest mode. In fact switching to a guest mode
* is very similar to exiting to userspace from rcu point of view. In
* addition CPU may stay in a guest mode for quite a long time (up to
* one time slice). Lets treat guest mode as quiescent state, just like
* we do with user-mode execution.
*/
if (!context_tracking_guest_enter()) {
instrumentation_begin();
rcu_virt_note_context_switch(smp_processor_id());
instrumentation_end();
}
}
static __always_inline void guest_exit_irqoff(void)
{
context_tracking_guest_exit();
instrumentation_begin();
/* Flush the guest cputime we spent on the guest */
vtime_account_guest_exit();
instrumentation_end();
}
static inline void guest_exit(void)
{
unsigned long flags;
local_irq_save(flags);
guest_exit_irqoff();
local_irq_restore(flags);
}
static inline int kvm_vcpu_exiting_guest_mode(struct kvm_vcpu *vcpu)
{
/*