[PATCH v2 01/21] KVM: x86/mmu: Track the associated kmem_cache in the MMU caches

Sean Christopherson
2020-06-22T20:11:33Z

Track the kmem_cache used for non-page KVM MMU memory caches instead of
passing in the associated kmem_cache when filling the cache. This will
allow consolidating code and other cleanups.

No functional change intended.

Reviewed-by: Ben Gardon <bgardon@google.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/mmu/mmu.c | 24 +++++++++++-------------
2 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index f8998e97457f..7b6ac8fad9c2 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -251,6 +251,7 @@ struct kvm_kernel_irq_routing_entry;
*/
struct kvm_mmu_memory_cache {
int nobjs;
+ struct kmem_cache *kmem_cache;
void *objects[KVM_NR_MEM_OBJS];
};

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index fdd05c233308..0830c195c9ed 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -1060,15 +1060,14 @@ static void walk_shadow_page_lockless_end(struct kvm_vcpu *vcpu)
local_irq_enable();
}

-static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
- struct kmem_cache *base_cache, int min)
+static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache, int min)
{
void *obj;

if (cache->nobjs >= min)
return 0;
while (cache->nobjs < ARRAY_SIZE(cache->objects)) {
- obj = kmem_cache_zalloc(base_cache, GFP_KERNEL_ACCOUNT);
+ obj = kmem_cache_zalloc(cache->kmem_cache, GFP_KERNEL_ACCOUNT);
if (!obj)
return cache->nobjs >= min ? 0 : -ENOMEM;
cache->objects[cache->nobjs++] = obj;
@@ -1081,11 +1080,10 @@ static int mmu_memory_cache_free_objects(struct kvm_mmu_memory_cache *cache)
return cache->nobjs;
}

-static void mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc,
- struct kmem_cache *cache)
+static void mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc)
{
while (mc->nobjs)
- kmem_cache_free(cache, mc->objects[--mc->nobjs]);
+ kmem_cache_free(mc->kmem_cache, mc->objects[--mc->nobjs]);
}

static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache *cache,
@@ -1115,25 +1113,22 @@ static int mmu_topup_memory_caches(struct kvm_vcpu *vcpu)
int r;

r = mmu_topup_memory_cache(&vcpu->arch.mmu_pte_list_desc_cache,
- pte_list_desc_cache, 8 + PTE_PREFETCH_NUM);
+ 8 + PTE_PREFETCH_NUM);
if (r)
goto out;
r = mmu_topup_memory_cache_page(&vcpu->arch.mmu_page_cache, 8);
if (r)
goto out;
- r = mmu_topup_memory_cache(&vcpu->arch.mmu_page_header_cache,
- mmu_page_header_cache, 4);
+ r = mmu_topup_memory_cache(&vcpu->arch.mmu_page_header_cache, 4);
out:
return r;
}

static void mmu_free_memory_caches(struct kvm_vcpu *vcpu)
{
- mmu_free_memory_cache(&vcpu->arch.mmu_pte_list_desc_cache,
- pte_list_desc_cache);
+ mmu_free_memory_cache(&vcpu->arch.mmu_pte_list_desc_cache);
mmu_free_memory_cache_page(&vcpu->arch.mmu_page_cache);
- mmu_free_memory_cache(&vcpu->arch.mmu_page_header_cache,
- mmu_page_header_cache);
+ mmu_free_memory_cache(&vcpu->arch.mmu_page_header_cache);
}

static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc)
@@ -5684,6 +5679,9 @@ int kvm_mmu_create(struct kvm_vcpu *vcpu)
uint i;
int ret;

+ vcpu->arch.mmu_pte_list_desc_cache.kmem_cache = pte_list_desc_cache;
+ vcpu->arch.mmu_page_header_cache.kmem_cache = mmu_page_header_cache;
+
vcpu->arch.mmu = &vcpu->arch.root_mmu;
vcpu->arch.walk_mmu = &vcpu->arch.root_mmu;

--
2.26.0