[PATCH v4 3/6] KVM: MMU: introduce pte_prefetch_topup_memory_cache()

From: Xiao Guangrong
Date: Thu Jul 01 2010 - 09:58:25 EST


Introduce this function to topup prefetch cache

Signed-off-by: Xiao Guangrong <xiaoguangrong@xxxxxxxxxxxxxx>
---
arch/x86/kvm/mmu.c | 25 +++++++++++++++++++++----
1 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index a0c5c31..6673484 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -89,6 +89,8 @@ module_param(oos_shadow, bool, 0644);
}
#endif

+#define PTE_PREFETCH_NUM 16
+
#define PT_FIRST_AVAIL_BITS_SHIFT 9
#define PT64_SECOND_AVAIL_BITS_SHIFT 52

@@ -290,15 +292,16 @@ static void __set_spte(u64 *sptep, u64 spte)
#endif
}

-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,
+ struct kmem_cache *base_cache, int min,
+ int max, gfp_t flags)
{
void *obj;

if (cache->nobjs >= min)
return 0;
- while (cache->nobjs < ARRAY_SIZE(cache->objects)) {
- obj = kmem_cache_zalloc(base_cache, GFP_KERNEL);
+ while (cache->nobjs < max) {
+ obj = kmem_cache_zalloc(base_cache, flags);
if (!obj)
return -ENOMEM;
cache->objects[cache->nobjs++] = obj;
@@ -306,6 +309,20 @@ static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
return 0;
}

+static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
+ struct kmem_cache *base_cache, int min)
+{
+ return __mmu_topup_memory_cache(cache, base_cache, min,
+ ARRAY_SIZE(cache->objects), GFP_KERNEL);
+}
+
+static int pte_prefetch_topup_memory_cache(struct kvm_vcpu *vcpu)
+{
+ return __mmu_topup_memory_cache(&vcpu->arch.mmu_rmap_desc_cache,
+ rmap_desc_cache, PTE_PREFETCH_NUM,
+ PTE_PREFETCH_NUM, GFP_ATOMIC);
+}
+
static void mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc,
struct kmem_cache *cache)
{
--
1.6.1.2


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