diff mbox series

[v8,2/3] KVM: x86: Dirty quota-based throttling of vcpus

Message ID 20230225204758.17726-3-shivam.kumar1@nutanix.com (mailing list archive)
State New, archived
Headers show
Series KVM: Dirty quota-based throttling | expand

Commit Message

Shivam Kumar Feb. 25, 2023, 8:47 p.m. UTC 
Call update_dirty_quota whenever a page is marked dirty with
appropriate arch-specific page size. Process the KVM request
KVM_REQ_DIRTY_QUOTA_EXIT (raised by update_dirty_quota) to exit to
userspace with exit reason KVM_EXIT_DIRTY_QUOTA_EXHAUSTED.

Suggested-by: Shaju Abraham <shaju.abraham@nutanix.com>
Suggested-by: Manish Mishra <manish.mishra@nutanix.com>
Co-developed-by: Anurag Madnawat <anurag.madnawat@nutanix.com>
Signed-off-by: Anurag Madnawat <anurag.madnawat@nutanix.com>
Signed-off-by: Shivam Kumar <shivam.kumar1@nutanix.com>
---
 arch/x86/kvm/Kconfig       |  1 +
 arch/x86/kvm/mmu/mmu.c     |  8 +++++++-
 arch/x86/kvm/mmu/spte.c    |  3 +++
 arch/x86/kvm/mmu/tdp_mmu.c |  3 +++
 arch/x86/kvm/vmx/vmx.c     |  5 +++++
 arch/x86/kvm/x86.c         | 16 ++++++++++++++++
 arch/x86/kvm/xen.c         | 12 +++++++++++-
 7 files changed, 46 insertions(+), 2 deletions(-)

Comments

Yuan Yao Feb. 28, 2023, 1:31 a.m. UTC | #1 
On Sat, Feb 25, 2023 at 08:47:59PM +0000, Shivam Kumar wrote:
> Call update_dirty_quota whenever a page is marked dirty with
> appropriate arch-specific page size. Process the KVM request
> KVM_REQ_DIRTY_QUOTA_EXIT (raised by update_dirty_quota) to exit to
> userspace with exit reason KVM_EXIT_DIRTY_QUOTA_EXHAUSTED.
>
> Suggested-by: Shaju Abraham <shaju.abraham@nutanix.com>
> Suggested-by: Manish Mishra <manish.mishra@nutanix.com>
> Co-developed-by: Anurag Madnawat <anurag.madnawat@nutanix.com>
> Signed-off-by: Anurag Madnawat <anurag.madnawat@nutanix.com>
> Signed-off-by: Shivam Kumar <shivam.kumar1@nutanix.com>
> ---
>  arch/x86/kvm/Kconfig       |  1 +
>  arch/x86/kvm/mmu/mmu.c     |  8 +++++++-
>  arch/x86/kvm/mmu/spte.c    |  3 +++
>  arch/x86/kvm/mmu/tdp_mmu.c |  3 +++
>  arch/x86/kvm/vmx/vmx.c     |  5 +++++
>  arch/x86/kvm/x86.c         | 16 ++++++++++++++++
>  arch/x86/kvm/xen.c         | 12 +++++++++++-
>  7 files changed, 46 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
> index 8e578311ca9d..8621a9512572 100644
> --- a/arch/x86/kvm/Kconfig
> +++ b/arch/x86/kvm/Kconfig
> @@ -48,6 +48,7 @@ config KVM
>  	select KVM_VFIO
>  	select SRCU
>  	select INTERVAL_TREE
> +	select HAVE_KVM_DIRTY_QUOTA
>  	select HAVE_KVM_PM_NOTIFIER if PM
>  	select KVM_GENERIC_HARDWARE_ENABLING
>  	help
> diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
> index c8ebe542c565..e0c8348ecdf1 100644
> --- a/arch/x86/kvm/mmu/mmu.c
> +++ b/arch/x86/kvm/mmu/mmu.c
> @@ -3323,8 +3323,14 @@ fast_pf_fix_direct_spte(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault,
>  	if (!try_cmpxchg64(sptep, &old_spte, new_spte))
>  		return false;
>
> -	if (is_writable_pte(new_spte) && !is_writable_pte(old_spte))
> +	if (is_writable_pte(new_spte) && !is_writable_pte(old_spte)) {
> +#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
> +		struct kvm_mmu_page *sp = sptep_to_sp(sptep);
> +
> +		update_dirty_quota(vcpu->kvm, (1L << SPTE_LEVEL_SHIFT(sp->role.level)));
> +#endif
>  		mark_page_dirty_in_slot(vcpu->kvm, fault->slot, fault->gfn);

Possible to call update_dirty_quota() from mark_page_dirty_in_slot() ?
Then other Architectures can be covered yet.

> +	}
>
>  	return true;
>  }
> diff --git a/arch/x86/kvm/mmu/spte.c b/arch/x86/kvm/mmu/spte.c
> index c15bfca3ed15..15f4f1d97ce9 100644
> --- a/arch/x86/kvm/mmu/spte.c
> +++ b/arch/x86/kvm/mmu/spte.c
> @@ -243,6 +243,9 @@ bool make_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
>  	if ((spte & PT_WRITABLE_MASK) && kvm_slot_dirty_track_enabled(slot)) {
>  		/* Enforced by kvm_mmu_hugepage_adjust. */
>  		WARN_ON(level > PG_LEVEL_4K);
> +#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
> +		update_dirty_quota(vcpu->kvm, (1L << SPTE_LEVEL_SHIFT(level)));
> +#endif
>  		mark_page_dirty_in_slot(vcpu->kvm, slot, gfn);
>  	}
>
> diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
> index 7c25dbf32ecc..4bf98e96343d 100644
> --- a/arch/x86/kvm/mmu/tdp_mmu.c
> +++ b/arch/x86/kvm/mmu/tdp_mmu.c
> @@ -358,6 +358,9 @@ static void handle_changed_spte_dirty_log(struct kvm *kvm, int as_id, gfn_t gfn,
>
>  	if ((!is_writable_pte(old_spte) || pfn_changed) &&
>  	    is_writable_pte(new_spte)) {
> +#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
> +		update_dirty_quota(kvm, (1L << SPTE_LEVEL_SHIFT(level)));
> +#endif
>  		slot = __gfn_to_memslot(__kvm_memslots(kvm, as_id), gfn);
>  		mark_page_dirty_in_slot(kvm, slot, gfn);
>  	}
> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
> index bcac3efcde41..da4c6342a647 100644
> --- a/arch/x86/kvm/vmx/vmx.c
> +++ b/arch/x86/kvm/vmx/vmx.c
> @@ -5861,6 +5861,11 @@ static int handle_invalid_guest_state(struct kvm_vcpu *vcpu)
>  		 */
>  		if (__xfer_to_guest_mode_work_pending())
>  			return 1;
> +
> +#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
> +		if (kvm_test_request(KVM_REQ_DIRTY_QUOTA_EXIT, vcpu))
> +			return 1;
> +#endif
>  	}
>
>  	return 1;
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 7713420abab0..1733be829197 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -3092,6 +3092,9 @@ static void kvm_setup_guest_pvclock(struct kvm_vcpu *v,
>
>  	guest_hv_clock->version = ++vcpu->hv_clock.version;
>
> +#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
> +	update_dirty_quota(v->kvm, PAGE_SIZE);
> +#endif
>  	mark_page_dirty_in_slot(v->kvm, gpc->memslot, gpc->gpa >> PAGE_SHIFT);
>  	read_unlock_irqrestore(&gpc->lock, flags);
>
> @@ -3566,6 +3569,9 @@ static void record_steal_time(struct kvm_vcpu *vcpu)
>   out:
>  	user_access_end();
>   dirty:
> +#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
> +	update_dirty_quota(vcpu->kvm, PAGE_SIZE);
> +#endif
>  	mark_page_dirty_in_slot(vcpu->kvm, ghc->memslot, gpa_to_gfn(ghc->gpa));
>  }
>
> @@ -4815,6 +4821,9 @@ static void kvm_steal_time_set_preempted(struct kvm_vcpu *vcpu)
>  	if (!copy_to_user_nofault(&st->preempted, &preempted, sizeof(preempted)))
>  		vcpu->arch.st.preempted = KVM_VCPU_PREEMPTED;
>
> +#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
> +	update_dirty_quota(vcpu->kvm, PAGE_SIZE);
> +#endif
>  	mark_page_dirty_in_slot(vcpu->kvm, ghc->memslot, gpa_to_gfn(ghc->gpa));
>  }
>
> @@ -10514,6 +10523,13 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
>  			r = 0;
>  			goto out;
>  		}
> +#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
> +		if (kvm_check_request(KVM_REQ_DIRTY_QUOTA_EXIT, vcpu)) {
> +			vcpu->run->exit_reason = KVM_EXIT_DIRTY_QUOTA_EXHAUSTED;
> +			r = 0;
> +			goto out;
> +		}
> +#endif
>
>  		/*
>  		 * KVM_REQ_HV_STIMER has to be processed after
> diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c
> index 40edf4d1974c..00a3ac438539 100644
> --- a/arch/x86/kvm/xen.c
> +++ b/arch/x86/kvm/xen.c
> @@ -435,9 +435,16 @@ static void kvm_xen_update_runstate_guest(struct kvm_vcpu *v, bool atomic)
>
>  	read_unlock_irqrestore(&gpc1->lock, flags);
>
> +#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
> +	update_dirty_quota(v->kvm, PAGE_SIZE);
> +#endif
>  	mark_page_dirty_in_slot(v->kvm, gpc1->memslot, gpc1->gpa >> PAGE_SHIFT);
> -	if (user_len2)
> +	if (user_len2) {
> +#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
> +		update_dirty_quota(v->kvm, PAGE_SIZE);
> +#endif
>  		mark_page_dirty_in_slot(v->kvm, gpc2->memslot, gpc2->gpa >> PAGE_SHIFT);
> +	}
>  }
>
>  void kvm_xen_update_runstate(struct kvm_vcpu *v, int state)
> @@ -549,6 +556,9 @@ void kvm_xen_inject_pending_events(struct kvm_vcpu *v)
>  	if (v->arch.xen.upcall_vector)
>  		kvm_xen_inject_vcpu_vector(v);
>
> +#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
> +	update_dirty_quota(v->kvm, PAGE_SIZE);
> +#endif
>  	mark_page_dirty_in_slot(v->kvm, gpc->memslot, gpc->gpa >> PAGE_SHIFT);
>  }
>
> --
> 2.22.3
>
Shivam Kumar March 4, 2023, 11:45 a.m. UTC | #2 
On 28/02/23 7:01 am, Yuan Yao wrote:
> On Sat, Feb 25, 2023 at 08:47:59PM +0000, Shivam Kumar wrote:
>> Call update_dirty_quota whenever a page is marked dirty with
>> appropriate arch-specific page size. Process the KVM request
>> KVM_REQ_DIRTY_QUOTA_EXIT (raised by update_dirty_quota) to exit to
>> userspace with exit reason KVM_EXIT_DIRTY_QUOTA_EXHAUSTED.
>>
>> Suggested-by: Shaju Abraham <shaju.abraham@nutanix.com>
>> Suggested-by: Manish Mishra <manish.mishra@nutanix.com>
>> Co-developed-by: Anurag Madnawat <anurag.madnawat@nutanix.com>
>> Signed-off-by: Anurag Madnawat <anurag.madnawat@nutanix.com>
>> Signed-off-by: Shivam Kumar <shivam.kumar1@nutanix.com>
>> ---
>>   arch/x86/kvm/Kconfig       |  1 +
>>   arch/x86/kvm/mmu/mmu.c     |  8 +++++++-
>>   arch/x86/kvm/mmu/spte.c    |  3 +++
>>   arch/x86/kvm/mmu/tdp_mmu.c |  3 +++
>>   arch/x86/kvm/vmx/vmx.c     |  5 +++++
>>   arch/x86/kvm/x86.c         | 16 ++++++++++++++++
>>   arch/x86/kvm/xen.c         | 12 +++++++++++-
>>   7 files changed, 46 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
>> index 8e578311ca9d..8621a9512572 100644
>> --- a/arch/x86/kvm/Kconfig
>> +++ b/arch/x86/kvm/Kconfig
>> @@ -48,6 +48,7 @@ config KVM
>>   	select KVM_VFIO
>>   	select SRCU
>>   	select INTERVAL_TREE
>> +	select HAVE_KVM_DIRTY_QUOTA
>>   	select HAVE_KVM_PM_NOTIFIER if PM
>>   	select KVM_GENERIC_HARDWARE_ENABLING
>>   	help
>> diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
>> index c8ebe542c565..e0c8348ecdf1 100644
>> --- a/arch/x86/kvm/mmu/mmu.c
>> +++ b/arch/x86/kvm/mmu/mmu.c
>> @@ -3323,8 +3323,14 @@ fast_pf_fix_direct_spte(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault,
>>   	if (!try_cmpxchg64(sptep, &old_spte, new_spte))
>>   		return false;
>>
>> -	if (is_writable_pte(new_spte) && !is_writable_pte(old_spte))
>> +	if (is_writable_pte(new_spte) && !is_writable_pte(old_spte)) {
>> +#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
>> +		struct kvm_mmu_page *sp = sptep_to_sp(sptep);
>> +
>> +		update_dirty_quota(vcpu->kvm, (1L << SPTE_LEVEL_SHIFT(sp->role.level)));
>> +#endif
>>   		mark_page_dirty_in_slot(vcpu->kvm, fault->slot, fault->gfn);
> 
> Possible to call update_dirty_quota() from mark_page_dirty_in_slot() ?
> Then other Architectures can be covered yet.

As Marc commented on the first patch of this patchset, 
mark_page_dirty_in_slot can be called multiple times for the same page, 
e.g. in the case of PML for nested guests. If bitmap-based dirty 
tracking is not enabled, we might not be able to handle those cases 
without adding an extra param (which can tell us whether a dirty quota 
update is required or not) in mark_page_dirty_in_slot. Thanks.

Thanks,
Shivam
diff mbox series

Patch

diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index 8e578311ca9d..8621a9512572 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -48,6 +48,7 @@  config KVM
 	select KVM_VFIO
 	select SRCU
 	select INTERVAL_TREE
+	select HAVE_KVM_DIRTY_QUOTA
 	select HAVE_KVM_PM_NOTIFIER if PM
 	select KVM_GENERIC_HARDWARE_ENABLING
 	help
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index c8ebe542c565..e0c8348ecdf1 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3323,8 +3323,14 @@  fast_pf_fix_direct_spte(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault,
 	if (!try_cmpxchg64(sptep, &old_spte, new_spte))
 		return false;
 
-	if (is_writable_pte(new_spte) && !is_writable_pte(old_spte))
+	if (is_writable_pte(new_spte) && !is_writable_pte(old_spte)) {
+#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
+		struct kvm_mmu_page *sp = sptep_to_sp(sptep);
+
+		update_dirty_quota(vcpu->kvm, (1L << SPTE_LEVEL_SHIFT(sp->role.level)));
+#endif
 		mark_page_dirty_in_slot(vcpu->kvm, fault->slot, fault->gfn);
+	}
 
 	return true;
 }
diff --git a/arch/x86/kvm/mmu/spte.c b/arch/x86/kvm/mmu/spte.c
index c15bfca3ed15..15f4f1d97ce9 100644
--- a/arch/x86/kvm/mmu/spte.c
+++ b/arch/x86/kvm/mmu/spte.c
@@ -243,6 +243,9 @@  bool make_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
 	if ((spte & PT_WRITABLE_MASK) && kvm_slot_dirty_track_enabled(slot)) {
 		/* Enforced by kvm_mmu_hugepage_adjust. */
 		WARN_ON(level > PG_LEVEL_4K);
+#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
+		update_dirty_quota(vcpu->kvm, (1L << SPTE_LEVEL_SHIFT(level)));
+#endif
 		mark_page_dirty_in_slot(vcpu->kvm, slot, gfn);
 	}
 
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 7c25dbf32ecc..4bf98e96343d 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -358,6 +358,9 @@  static void handle_changed_spte_dirty_log(struct kvm *kvm, int as_id, gfn_t gfn,
 
 	if ((!is_writable_pte(old_spte) || pfn_changed) &&
 	    is_writable_pte(new_spte)) {
+#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
+		update_dirty_quota(kvm, (1L << SPTE_LEVEL_SHIFT(level)));
+#endif
 		slot = __gfn_to_memslot(__kvm_memslots(kvm, as_id), gfn);
 		mark_page_dirty_in_slot(kvm, slot, gfn);
 	}
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index bcac3efcde41..da4c6342a647 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -5861,6 +5861,11 @@  static int handle_invalid_guest_state(struct kvm_vcpu *vcpu)
 		 */
 		if (__xfer_to_guest_mode_work_pending())
 			return 1;
+
+#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
+		if (kvm_test_request(KVM_REQ_DIRTY_QUOTA_EXIT, vcpu))
+			return 1;
+#endif
 	}
 
 	return 1;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 7713420abab0..1733be829197 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3092,6 +3092,9 @@  static void kvm_setup_guest_pvclock(struct kvm_vcpu *v,
 
 	guest_hv_clock->version = ++vcpu->hv_clock.version;
 
+#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
+	update_dirty_quota(v->kvm, PAGE_SIZE);
+#endif
 	mark_page_dirty_in_slot(v->kvm, gpc->memslot, gpc->gpa >> PAGE_SHIFT);
 	read_unlock_irqrestore(&gpc->lock, flags);
 
@@ -3566,6 +3569,9 @@  static void record_steal_time(struct kvm_vcpu *vcpu)
  out:
 	user_access_end();
  dirty:
+#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
+	update_dirty_quota(vcpu->kvm, PAGE_SIZE);
+#endif
 	mark_page_dirty_in_slot(vcpu->kvm, ghc->memslot, gpa_to_gfn(ghc->gpa));
 }
 
@@ -4815,6 +4821,9 @@  static void kvm_steal_time_set_preempted(struct kvm_vcpu *vcpu)
 	if (!copy_to_user_nofault(&st->preempted, &preempted, sizeof(preempted)))
 		vcpu->arch.st.preempted = KVM_VCPU_PREEMPTED;
 
+#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
+	update_dirty_quota(vcpu->kvm, PAGE_SIZE);
+#endif
 	mark_page_dirty_in_slot(vcpu->kvm, ghc->memslot, gpa_to_gfn(ghc->gpa));
 }
 
@@ -10514,6 +10523,13 @@  static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
 			r = 0;
 			goto out;
 		}
+#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
+		if (kvm_check_request(KVM_REQ_DIRTY_QUOTA_EXIT, vcpu)) {
+			vcpu->run->exit_reason = KVM_EXIT_DIRTY_QUOTA_EXHAUSTED;
+			r = 0;
+			goto out;
+		}
+#endif
 
 		/*
 		 * KVM_REQ_HV_STIMER has to be processed after
diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c
index 40edf4d1974c..00a3ac438539 100644
--- a/arch/x86/kvm/xen.c
+++ b/arch/x86/kvm/xen.c
@@ -435,9 +435,16 @@  static void kvm_xen_update_runstate_guest(struct kvm_vcpu *v, bool atomic)
 
 	read_unlock_irqrestore(&gpc1->lock, flags);
 
+#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
+	update_dirty_quota(v->kvm, PAGE_SIZE);
+#endif
 	mark_page_dirty_in_slot(v->kvm, gpc1->memslot, gpc1->gpa >> PAGE_SHIFT);
-	if (user_len2)
+	if (user_len2) {
+#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
+		update_dirty_quota(v->kvm, PAGE_SIZE);
+#endif
 		mark_page_dirty_in_slot(v->kvm, gpc2->memslot, gpc2->gpa >> PAGE_SHIFT);
+	}
 }
 
 void kvm_xen_update_runstate(struct kvm_vcpu *v, int state)
@@ -549,6 +556,9 @@  void kvm_xen_inject_pending_events(struct kvm_vcpu *v)
 	if (v->arch.xen.upcall_vector)
 		kvm_xen_inject_vcpu_vector(v);
 
+#ifdef CONFIG_HAVE_KVM_DIRTY_QUOTA
+	update_dirty_quota(v->kvm, PAGE_SIZE);
+#endif
 	mark_page_dirty_in_slot(v->kvm, gpc->memslot, gpc->gpa >> PAGE_SHIFT);
 }