Commit d38ba8cc authored by Yosry Ahmed's avatar Yosry Ahmed Committed by Sean Christopherson
Browse files

KVM: arm64/mmu: count KVM s2 mmu usage in secondary pagetable stats 



Count the pages used by KVM in arm64 for stage2 mmu in memory stats
under secondary pagetable stats (e.g. "SecPageTables" in /proc/meminfo)
to give better visibility into the memory consumption of KVM mmu in a
similar way to how normal user page tables are accounted.

Signed-off-by: default avatarYosry Ahmed <yosryahmed@google.com>
Reviewed-by: default avatarOliver Upton <oliver.upton@linux.dev>
Reviewed-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220823004639.2387269-5-yosryahmed@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 43a063ca

arch/arm64/kvm/mmu.c

+32 −4
Original line number Diff line number Diff line
@@ -92,9 +92,13 @@ static bool kvm_is_device_pfn(unsigned long pfn) 
static void *stage2_memcache_zalloc_page(void *arg)

{

	struct kvm_mmu_memory_cache *mc = arg;

	void *virt;



	/* Allocated with __GFP_ZERO, so no need to zero */

	return kvm_mmu_memory_cache_alloc(mc);

	virt = kvm_mmu_memory_cache_alloc(mc);

	if (virt)

		kvm_account_pgtable_pages(virt, 1);

	return virt;

}



static void *kvm_host_zalloc_pages_exact(size_t size)
@@ -102,6 +106,21 @@ static void *kvm_host_zalloc_pages_exact(size_t size) 
	return alloc_pages_exact(size, GFP_KERNEL_ACCOUNT | __GFP_ZERO);

}



static void *kvm_s2_zalloc_pages_exact(size_t size)

{

	void *virt = kvm_host_zalloc_pages_exact(size);



	if (virt)

		kvm_account_pgtable_pages(virt, (size >> PAGE_SHIFT));

	return virt;

}



static void kvm_s2_free_pages_exact(void *virt, size_t size)

{

	kvm_account_pgtable_pages(virt, -(size >> PAGE_SHIFT));

	free_pages_exact(virt, size);

}



static void kvm_host_get_page(void *addr)

{

	get_page(virt_to_page(addr));
@@ -112,6 +131,15 @@ static void kvm_host_put_page(void *addr) 
	put_page(virt_to_page(addr));

}



static void kvm_s2_put_page(void *addr)

{

	struct page *p = virt_to_page(addr);

	/* Dropping last refcount, the page will be freed */

	if (page_count(p) == 1)

		kvm_account_pgtable_pages(addr, -1);

	put_page(p);

}



static int kvm_host_page_count(void *addr)

{

	return page_count(virt_to_page(addr));
@@ -625,10 +653,10 @@ static int get_user_mapping_size(struct kvm *kvm, u64 addr) 


static struct kvm_pgtable_mm_ops kvm_s2_mm_ops = {

	.zalloc_page		= stage2_memcache_zalloc_page,

	.zalloc_pages_exact	= kvm_host_zalloc_pages_exact,

	.free_pages_exact	= free_pages_exact,

	.zalloc_pages_exact	= kvm_s2_zalloc_pages_exact,

	.free_pages_exact	= kvm_s2_free_pages_exact,

	.get_page		= kvm_host_get_page,

	.put_page		= kvm_host_put_page,

	.put_page		= kvm_s2_put_page,

	.page_count		= kvm_host_page_count,

	.phys_to_virt		= kvm_host_va,

	.virt_to_phys		= kvm_host_pa,