diff mbox series

[16/21] KVM: arm64: Drop @max param from mmu_topup_memory_cache()

Message ID 20200605213853.14959-17-sean.j.christopherson@intel.com (mailing list archive)
State New, archived
Headers show
Series KVM: Cleanup and unify kvm_mmu_memory_cache usage | expand

Commit Message

Sean Christopherson June 5, 2020, 9:38 p.m. UTC
Replace the @max param in mmu_topup_memory_cache() and instead use
ARRAY_SIZE() to terminate the loop to fill the cache.  This removes a
BUG_ON() and sets the stage for moving arm64 to the common memory cache
implementation.

No functional change intended.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
 arch/arm64/kvm/mmu.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

Comments

Ben Gardon June 10, 2020, 10 p.m. UTC | #1
On Fri, Jun 5, 2020 at 2:39 PM Sean Christopherson
<sean.j.christopherson@intel.com> wrote:
>
> Replace the @max param in mmu_topup_memory_cache() and instead use
> ARRAY_SIZE() to terminate the loop to fill the cache.  This removes a
> BUG_ON() and sets the stage for moving arm64 to the common memory cache
> implementation.
>
> No functional change intended.
>
> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
> ---
>  arch/arm64/kvm/mmu.c | 12 ++++--------
>  1 file changed, 4 insertions(+), 8 deletions(-)
>
> diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
> index a1f6bc70c4e4..9398b66f8a87 100644
> --- a/arch/arm64/kvm/mmu.c
> +++ b/arch/arm64/kvm/mmu.c
> @@ -124,15 +124,13 @@ static void stage2_dissolve_pud(struct kvm *kvm, phys_addr_t addr, pud_t *pudp)
>         put_page(virt_to_page(pudp));
>  }
>
> -static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
> -                                 int min, int max)
> +static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache, int min)
>  {
>         void *page;
>
> -       BUG_ON(max > KVM_NR_MEM_OBJS);
KVM_NR_MEM_OBJS should be undefined as of patch 14 in this series. I'd
recommend changing this to use the new constant you defined in that
patch.
>         if (cache->nobjs >= min)
>                 return 0;
> -       while (cache->nobjs < max) {
> +       while (cache->nobjs < ARRAY_SIZE(cache->objects)) {
>                 page = (void *)__get_free_page(GFP_PGTABLE_USER);
>                 if (!page)
>                         return -ENOMEM;
> @@ -1356,8 +1354,7 @@ int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa,
>                         pte = kvm_s2pte_mkwrite(pte);
>
>                 ret = mmu_topup_memory_cache(&cache,
> -                                            kvm_mmu_cache_min_pages(kvm),
> -                                            KVM_NR_MEM_OBJS);
See above, KVM_NR_MEM_OBJS is undefined as of patch 14.
> +                                            kvm_mmu_cache_min_pages(kvm));
>                 if (ret)
>                         goto out;
>                 spin_lock(&kvm->mmu_lock);
> @@ -1737,8 +1734,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
>         up_read(&current->mm->mmap_sem);
>
>         /* We need minimum second+third level pages */
> -       ret = mmu_topup_memory_cache(memcache, kvm_mmu_cache_min_pages(kvm),
> -                                    KVM_NR_MEM_OBJS);
See above, KVM_NR_MEM_OBJS is undefined as of patch 14.
> +       ret = mmu_topup_memory_cache(memcache, kvm_mmu_cache_min_pages(kvm));
>         if (ret)
>                 return ret;
>
> --
> 2.26.0
>
Sean Christopherson June 11, 2020, 3:59 p.m. UTC | #2
On Wed, Jun 10, 2020 at 03:00:47PM -0700, Ben Gardon wrote:
> On Fri, Jun 5, 2020 at 2:39 PM Sean Christopherson
> <sean.j.christopherson@intel.com> wrote:
> >
> > Replace the @max param in mmu_topup_memory_cache() and instead use
> > ARRAY_SIZE() to terminate the loop to fill the cache.  This removes a
> > BUG_ON() and sets the stage for moving arm64 to the common memory cache
> > implementation.
> >
> > No functional change intended.
> >
> > Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
> > ---
> >  arch/arm64/kvm/mmu.c | 12 ++++--------
> >  1 file changed, 4 insertions(+), 8 deletions(-)
> >
> > diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
> > index a1f6bc70c4e4..9398b66f8a87 100644
> > --- a/arch/arm64/kvm/mmu.c
> > +++ b/arch/arm64/kvm/mmu.c
> > @@ -124,15 +124,13 @@ static void stage2_dissolve_pud(struct kvm *kvm, phys_addr_t addr, pud_t *pudp)
> >         put_page(virt_to_page(pudp));
> >  }
> >
> > -static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
> > -                                 int min, int max)
> > +static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache, int min)
> >  {
> >         void *page;
> >
> > -       BUG_ON(max > KVM_NR_MEM_OBJS);
> KVM_NR_MEM_OBJS should be undefined as of patch 14 in this series. I'd
> recommend changing this to use the new constant you defined in that
> patch.

My intent was to leave KVM_NR_MEM_OBJS defined by arm64 and MIPS until they
move to the common implementation, e.g. this should be defined in
arch/arm64/include/asm/kvm_host.h until patch 18.  I'll get cross-compiling
setup so I can properly test bisection before sending v2.

> >         if (cache->nobjs >= min)
> >                 return 0;
> > -       while (cache->nobjs < max) {
> > +       while (cache->nobjs < ARRAY_SIZE(cache->objects)) {
> >                 page = (void *)__get_free_page(GFP_PGTABLE_USER);
> >                 if (!page)
> >                         return -ENOMEM;
> > @@ -1356,8 +1354,7 @@ int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa,
> >                         pte = kvm_s2pte_mkwrite(pte);
> >
> >                 ret = mmu_topup_memory_cache(&cache,
> > -                                            kvm_mmu_cache_min_pages(kvm),
> > -                                            KVM_NR_MEM_OBJS);
> See above, KVM_NR_MEM_OBJS is undefined as of patch 14.
> > +                                            kvm_mmu_cache_min_pages(kvm));
> >                 if (ret)
> >                         goto out;
> >                 spin_lock(&kvm->mmu_lock);
> > @@ -1737,8 +1734,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
> >         up_read(&current->mm->mmap_sem);
> >
> >         /* We need minimum second+third level pages */
> > -       ret = mmu_topup_memory_cache(memcache, kvm_mmu_cache_min_pages(kvm),
> > -                                    KVM_NR_MEM_OBJS);
> See above, KVM_NR_MEM_OBJS is undefined as of patch 14.
> > +       ret = mmu_topup_memory_cache(memcache, kvm_mmu_cache_min_pages(kvm));
> >         if (ret)
> >                 return ret;
> >
> > --
> > 2.26.0
> >
diff mbox series

Patch

diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index a1f6bc70c4e4..9398b66f8a87 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -124,15 +124,13 @@  static void stage2_dissolve_pud(struct kvm *kvm, phys_addr_t addr, pud_t *pudp)
 	put_page(virt_to_page(pudp));
 }
 
-static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
-				  int min, int max)
+static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache, int min)
 {
 	void *page;
 
-	BUG_ON(max > KVM_NR_MEM_OBJS);
 	if (cache->nobjs >= min)
 		return 0;
-	while (cache->nobjs < max) {
+	while (cache->nobjs < ARRAY_SIZE(cache->objects)) {
 		page = (void *)__get_free_page(GFP_PGTABLE_USER);
 		if (!page)
 			return -ENOMEM;
@@ -1356,8 +1354,7 @@  int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa,
 			pte = kvm_s2pte_mkwrite(pte);
 
 		ret = mmu_topup_memory_cache(&cache,
-					     kvm_mmu_cache_min_pages(kvm),
-					     KVM_NR_MEM_OBJS);
+					     kvm_mmu_cache_min_pages(kvm));
 		if (ret)
 			goto out;
 		spin_lock(&kvm->mmu_lock);
@@ -1737,8 +1734,7 @@  static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
 	up_read(&current->mm->mmap_sem);
 
 	/* We need minimum second+third level pages */
-	ret = mmu_topup_memory_cache(memcache, kvm_mmu_cache_min_pages(kvm),
-				     KVM_NR_MEM_OBJS);
+	ret = mmu_topup_memory_cache(memcache, kvm_mmu_cache_min_pages(kvm));
 	if (ret)
 		return ret;