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* [PATCH] KVM: x86/mmu: Stash 'kvm' in a local variable in kvm_mmu_free_roots()
@ 2020-09-23 19:12 Sean Christopherson
  2020-09-24 12:42 ` Vitaly Kuznetsov
  2020-09-25 20:24 ` Paolo Bonzini
  0 siblings, 2 replies; 4+ messages in thread
From: Sean Christopherson @ 2020-09-23 19:12 UTC (permalink / raw)
  To: Paolo Bonzini
  Cc: Sean Christopherson, Vitaly Kuznetsov, Wanpeng Li, Jim Mattson,
	Joerg Roedel, kvm, linux-kernel

To make kvm_mmu_free_roots() a bit more readable, capture 'kvm' in a
local variable instead of doing vcpu->kvm over and over (and over).

No functional change intended.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
 arch/x86/kvm/mmu/mmu.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 76c5826e29a2..cdc498093450 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3603,6 +3603,7 @@ static void mmu_free_root_page(struct kvm *kvm, hpa_t *root_hpa,
 void kvm_mmu_free_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
 			ulong roots_to_free)
 {
+	struct kvm *kvm = vcpu->kvm;
 	int i;
 	LIST_HEAD(invalid_list);
 	bool free_active_root = roots_to_free & KVM_MMU_ROOT_CURRENT;
@@ -3620,22 +3621,21 @@ void kvm_mmu_free_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
 			return;
 	}
 
-	spin_lock(&vcpu->kvm->mmu_lock);
+	spin_lock(&kvm->mmu_lock);
 
 	for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++)
 		if (roots_to_free & KVM_MMU_ROOT_PREVIOUS(i))
-			mmu_free_root_page(vcpu->kvm, &mmu->prev_roots[i].hpa,
+			mmu_free_root_page(kvm, &mmu->prev_roots[i].hpa,
 					   &invalid_list);
 
 	if (free_active_root) {
 		if (mmu->shadow_root_level >= PT64_ROOT_4LEVEL &&
 		    (mmu->root_level >= PT64_ROOT_4LEVEL || mmu->direct_map)) {
-			mmu_free_root_page(vcpu->kvm, &mmu->root_hpa,
-					   &invalid_list);
+			mmu_free_root_page(kvm, &mmu->root_hpa, &invalid_list);
 		} else {
 			for (i = 0; i < 4; ++i)
 				if (mmu->pae_root[i] != 0)
-					mmu_free_root_page(vcpu->kvm,
+					mmu_free_root_page(kvm,
 							   &mmu->pae_root[i],
 							   &invalid_list);
 			mmu->root_hpa = INVALID_PAGE;
@@ -3643,8 +3643,8 @@ void kvm_mmu_free_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
 		mmu->root_pgd = 0;
 	}
 
-	kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list);
-	spin_unlock(&vcpu->kvm->mmu_lock);
+	kvm_mmu_commit_zap_page(kvm, &invalid_list);
+	spin_unlock(&kvm->mmu_lock);
 }
 EXPORT_SYMBOL_GPL(kvm_mmu_free_roots);
 
-- 
2.28.0


^ permalink raw reply related	[flat|nested] 4+ messages in thread

* Re: [PATCH] KVM: x86/mmu: Stash 'kvm' in a local variable in kvm_mmu_free_roots()
  2020-09-23 19:12 [PATCH] KVM: x86/mmu: Stash 'kvm' in a local variable in kvm_mmu_free_roots() Sean Christopherson
@ 2020-09-24 12:42 ` Vitaly Kuznetsov
  2020-09-24 14:39   ` Sean Christopherson
  2020-09-25 20:24 ` Paolo Bonzini
  1 sibling, 1 reply; 4+ messages in thread
From: Vitaly Kuznetsov @ 2020-09-24 12:42 UTC (permalink / raw)
  To: Sean Christopherson, Paolo Bonzini
  Cc: Wanpeng Li, Jim Mattson, Joerg Roedel, kvm, linux-kernel

Sean Christopherson <sean.j.christopherson@intel.com> writes:

> To make kvm_mmu_free_roots() a bit more readable, capture 'kvm' in a
> local variable instead of doing vcpu->kvm over and over (and over).
>
> No functional change intended.
>
> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
> ---
>  arch/x86/kvm/mmu/mmu.c | 14 +++++++-------
>  1 file changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
> index 76c5826e29a2..cdc498093450 100644
> --- a/arch/x86/kvm/mmu/mmu.c
> +++ b/arch/x86/kvm/mmu/mmu.c
> @@ -3603,6 +3603,7 @@ static void mmu_free_root_page(struct kvm *kvm, hpa_t *root_hpa,
>  void kvm_mmu_free_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
>  			ulong roots_to_free)
>  {
> +	struct kvm *kvm = vcpu->kvm;
>  	int i;
>  	LIST_HEAD(invalid_list);
>  	bool free_active_root = roots_to_free & KVM_MMU_ROOT_CURRENT;
> @@ -3620,22 +3621,21 @@ void kvm_mmu_free_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
>  			return;
>  	}
>  
> -	spin_lock(&vcpu->kvm->mmu_lock);
> +	spin_lock(&kvm->mmu_lock);
>  
>  	for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++)
>  		if (roots_to_free & KVM_MMU_ROOT_PREVIOUS(i))
> -			mmu_free_root_page(vcpu->kvm, &mmu->prev_roots[i].hpa,
> +			mmu_free_root_page(kvm, &mmu->prev_roots[i].hpa,
>  					   &invalid_list);
>  
>  	if (free_active_root) {
>  		if (mmu->shadow_root_level >= PT64_ROOT_4LEVEL &&
>  		    (mmu->root_level >= PT64_ROOT_4LEVEL || mmu->direct_map)) {
> -			mmu_free_root_page(vcpu->kvm, &mmu->root_hpa,
> -					   &invalid_list);
> +			mmu_free_root_page(kvm, &mmu->root_hpa, &invalid_list);
>  		} else {
>  			for (i = 0; i < 4; ++i)
>  				if (mmu->pae_root[i] != 0)
> -					mmu_free_root_page(vcpu->kvm,
> +					mmu_free_root_page(kvm,
>  							   &mmu->pae_root[i],
>  							   &invalid_list);
>  			mmu->root_hpa = INVALID_PAGE;
> @@ -3643,8 +3643,8 @@ void kvm_mmu_free_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
>  		mmu->root_pgd = 0;
>  	}
>  
> -	kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list);
> -	spin_unlock(&vcpu->kvm->mmu_lock);
> +	kvm_mmu_commit_zap_page(kvm, &invalid_list);
> +	spin_unlock(&kvm->mmu_lock);
>  }
>  EXPORT_SYMBOL_GPL(kvm_mmu_free_roots);

What about kvm_mmu_get_page(), make_mmu_pages_available(),
mmu_alloc_root(), kvm_mmu_sync_roots(), direct_page_fault(),
kvm_mmu_pte_write() which seem to be using the same ugly pattern? :-)

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>

-- 
Vitaly


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH] KVM: x86/mmu: Stash 'kvm' in a local variable in kvm_mmu_free_roots()
  2020-09-24 12:42 ` Vitaly Kuznetsov
@ 2020-09-24 14:39   ` Sean Christopherson
  0 siblings, 0 replies; 4+ messages in thread
From: Sean Christopherson @ 2020-09-24 14:39 UTC (permalink / raw)
  To: Vitaly Kuznetsov
  Cc: Paolo Bonzini, Wanpeng Li, Jim Mattson, Joerg Roedel, kvm, linux-kernel

On Thu, Sep 24, 2020 at 02:42:19PM +0200, Vitaly Kuznetsov wrote:
> What about kvm_mmu_get_page(), make_mmu_pages_available(),
> mmu_alloc_root(), kvm_mmu_sync_roots(), direct_page_fault(),
> kvm_mmu_pte_write() which seem to be using the same ugly pattern? :-)

Heh, good question.  I guess only kvm_mmu_free_roots() managed to cross over
the threshold from "that's ugly" to "this is ridiculous".

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH] KVM: x86/mmu: Stash 'kvm' in a local variable in kvm_mmu_free_roots()
  2020-09-23 19:12 [PATCH] KVM: x86/mmu: Stash 'kvm' in a local variable in kvm_mmu_free_roots() Sean Christopherson
  2020-09-24 12:42 ` Vitaly Kuznetsov
@ 2020-09-25 20:24 ` Paolo Bonzini
  1 sibling, 0 replies; 4+ messages in thread
From: Paolo Bonzini @ 2020-09-25 20:24 UTC (permalink / raw)
  To: Sean Christopherson
  Cc: Vitaly Kuznetsov, Wanpeng Li, Jim Mattson, Joerg Roedel, kvm,
	linux-kernel

On 23/09/20 21:12, Sean Christopherson wrote:
> To make kvm_mmu_free_roots() a bit more readable, capture 'kvm' in a
> local variable instead of doing vcpu->kvm over and over (and over).
> 
> No functional change intended.
> 
> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
> ---
>  arch/x86/kvm/mmu/mmu.c | 14 +++++++-------
>  1 file changed, 7 insertions(+), 7 deletions(-)
> 
> diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
> index 76c5826e29a2..cdc498093450 100644
> --- a/arch/x86/kvm/mmu/mmu.c
> +++ b/arch/x86/kvm/mmu/mmu.c
> @@ -3603,6 +3603,7 @@ static void mmu_free_root_page(struct kvm *kvm, hpa_t *root_hpa,
>  void kvm_mmu_free_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
>  			ulong roots_to_free)
>  {
> +	struct kvm *kvm = vcpu->kvm;
>  	int i;
>  	LIST_HEAD(invalid_list);
>  	bool free_active_root = roots_to_free & KVM_MMU_ROOT_CURRENT;
> @@ -3620,22 +3621,21 @@ void kvm_mmu_free_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
>  			return;
>  	}
>  
> -	spin_lock(&vcpu->kvm->mmu_lock);
> +	spin_lock(&kvm->mmu_lock);
>  
>  	for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++)
>  		if (roots_to_free & KVM_MMU_ROOT_PREVIOUS(i))
> -			mmu_free_root_page(vcpu->kvm, &mmu->prev_roots[i].hpa,
> +			mmu_free_root_page(kvm, &mmu->prev_roots[i].hpa,
>  					   &invalid_list);
>  
>  	if (free_active_root) {
>  		if (mmu->shadow_root_level >= PT64_ROOT_4LEVEL &&
>  		    (mmu->root_level >= PT64_ROOT_4LEVEL || mmu->direct_map)) {
> -			mmu_free_root_page(vcpu->kvm, &mmu->root_hpa,
> -					   &invalid_list);
> +			mmu_free_root_page(kvm, &mmu->root_hpa, &invalid_list);
>  		} else {
>  			for (i = 0; i < 4; ++i)
>  				if (mmu->pae_root[i] != 0)
> -					mmu_free_root_page(vcpu->kvm,
> +					mmu_free_root_page(kvm,
>  							   &mmu->pae_root[i],
>  							   &invalid_list);
>  			mmu->root_hpa = INVALID_PAGE;
> @@ -3643,8 +3643,8 @@ void kvm_mmu_free_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
>  		mmu->root_pgd = 0;
>  	}
>  
> -	kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list);
> -	spin_unlock(&vcpu->kvm->mmu_lock);
> +	kvm_mmu_commit_zap_page(kvm, &invalid_list);
> +	spin_unlock(&kvm->mmu_lock);
>  }
>  EXPORT_SYMBOL_GPL(kvm_mmu_free_roots);
>  
> 

Queued this one, for now.

Paolo


^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2020-09-25 20:33 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2020-09-23 19:12 [PATCH] KVM: x86/mmu: Stash 'kvm' in a local variable in kvm_mmu_free_roots() Sean Christopherson
2020-09-24 12:42 ` Vitaly Kuznetsov
2020-09-24 14:39   ` Sean Christopherson
2020-09-25 20:24 ` Paolo Bonzini

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