Commit b5a33a75 authored by Avi Kivity's avatar Avi Kivity
Browse files

KVM: Use slab caches to allocate mmu data structures 



Better leak detection, statistics, memory use, speed -- goodness all
around.

Signed-off-by: default avatarAvi Kivity <avi@qumranet.com>
parent 417726a3

drivers/kvm/kvm.h

+3 −0
Original line number Diff line number Diff line
@@ -433,6 +433,9 @@ extern struct kvm_arch_ops *kvm_arch_ops; 
int kvm_init_arch(struct kvm_arch_ops *ops, struct module *module);

void kvm_exit_arch(void);



int kvm_mmu_module_init(void);

void kvm_mmu_module_exit(void);



void kvm_mmu_destroy(struct kvm_vcpu *vcpu);

int kvm_mmu_create(struct kvm_vcpu *vcpu);

int kvm_mmu_setup(struct kvm_vcpu *vcpu);

drivers/kvm/kvm_main.c

+7 −0
Original line number Diff line number Diff line
@@ -3063,6 +3063,10 @@ static __init int kvm_init(void) 
	static struct page *bad_page;

	int r;



	r = kvm_mmu_module_init();

	if (r)

		goto out4;



	r = register_filesystem(&kvm_fs_type);

	if (r)

		goto out3;
@@ -3091,6 +3095,8 @@ static __init int kvm_init(void) 
out2:

	unregister_filesystem(&kvm_fs_type);

out3:

	kvm_mmu_module_exit();

out4:

	return r;

}
@@ -3100,6 +3106,7 @@ static __exit void kvm_exit(void) 
	__free_page(pfn_to_page(bad_page_address >> PAGE_SHIFT));

	mntput(kvmfs_mnt);

	unregister_filesystem(&kvm_fs_type);

	kvm_mmu_module_exit();

}



module_init(kvm_init)

drivers/kvm/mmu.c

+35 −4
Original line number Diff line number Diff line
@@ -159,6 +159,9 @@ struct kvm_rmap_desc { 
	struct kvm_rmap_desc *more;

};



static struct kmem_cache *pte_chain_cache;

static struct kmem_cache *rmap_desc_cache;



static int is_write_protection(struct kvm_vcpu *vcpu)

{

	return vcpu->cr0 & CR0_WP_MASK;
@@ -196,14 +199,14 @@ static int is_rmap_pte(u64 pte) 
}



static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,

				  size_t objsize, int min)

				  struct kmem_cache *base_cache, int min)

{

	void *obj;



	if (cache->nobjs >= min)

		return 0;

	while (cache->nobjs < ARRAY_SIZE(cache->objects)) {

		obj = kzalloc(objsize, GFP_NOWAIT);

		obj = kmem_cache_zalloc(base_cache, GFP_NOWAIT);

		if (!obj)

			return -ENOMEM;

		cache->objects[cache->nobjs++] = obj;
@@ -222,11 +225,11 @@ static int mmu_topup_memory_caches(struct kvm_vcpu *vcpu) 
	int r;



	r = mmu_topup_memory_cache(&vcpu->mmu_pte_chain_cache,

				   sizeof(struct kvm_pte_chain), 4);

				   pte_chain_cache, 4);

	if (r)

		goto out;

	r = mmu_topup_memory_cache(&vcpu->mmu_rmap_desc_cache,

				   sizeof(struct kvm_rmap_desc), 1);

				   rmap_desc_cache, 1);

out:

	return r;

}
@@ -1333,6 +1336,34 @@ void kvm_mmu_zap_all(struct kvm_vcpu *vcpu) 
	init_kvm_mmu(vcpu);

}



void kvm_mmu_module_exit(void)

{

	if (pte_chain_cache)

		kmem_cache_destroy(pte_chain_cache);

	if (rmap_desc_cache)

		kmem_cache_destroy(rmap_desc_cache);

}



int kvm_mmu_module_init(void)

{

	pte_chain_cache = kmem_cache_create("kvm_pte_chain",

					    sizeof(struct kvm_pte_chain),

					    0, 0, NULL, NULL);

	if (!pte_chain_cache)

		goto nomem;

	rmap_desc_cache = kmem_cache_create("kvm_rmap_desc",

					    sizeof(struct kvm_rmap_desc),

					    0, 0, NULL, NULL);

	if (!rmap_desc_cache)

		goto nomem;



	return 0;



nomem:

	kvm_mmu_module_exit();

	return -ENOMEM;

}



#ifdef AUDIT



static const char *audit_msg;