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: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
Reviewed-by: Oliver Upton <oliver.upton@xxxxxxxxx>
---
arch/arm64/kvm/mmu.c | 36 ++++++++++++++++++++++++++++++++----
1 file changed, 32 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 87f1cd0df36ea..9d5a8e93d2fdc 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -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,
--
2.37.0.rc0.161.g10f37bed90-goog
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