Count the pages used by KVM in arm64 for stage2 mmu in secondary pagetable
stats.
Signed-off-by: Yosry Ahmed <[email protected]>
---
arch/arm64/kvm/mmu.c | 35 +++++++++++++++++++++++++++++++----
1 file changed, 31 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 53ae2c0640bc..fc5030307cce 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 +106,20 @@ 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 +130,15 @@ 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));
@@ -603,10 +630,10 @@ 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,
--
2.36.0.464.gb9c8b46e94-goog
On Mon, 02 May 2022 08:24:28 +0100,
Oliver Upton <[email protected]> wrote:
>
> Hi Yosry,
>
> On Fri, Apr 29, 2022 at 08:11:31PM +0000, Yosry Ahmed wrote:
> > Count the pages used by KVM in arm64 for stage2 mmu in secondary pagetable
> > stats.
> >
> > Signed-off-by: Yosry Ahmed <[email protected]>
> > ---
> > arch/arm64/kvm/mmu.c | 35 +++++++++++++++++++++++++++++++----
> > 1 file changed, 31 insertions(+), 4 deletions(-)
> >
> > diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
> > index 53ae2c0640bc..fc5030307cce 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);
>
> Sorry I didn't say it last time around, would now be a good time to
> clean up the funky sign convention of kvm_mod_used_mmu_pages()? Or limit
> the funk to just x86 :)
Indeed. I pointed this out in my initial review of this series, and
expected these to be gone by now.
M.
--
Without deviation from the norm, progress is not possible.
Hi Yosry,
On Fri, Apr 29, 2022 at 08:11:31PM +0000, Yosry Ahmed wrote:
> Count the pages used by KVM in arm64 for stage2 mmu in secondary pagetable
> stats.
>
> Signed-off-by: Yosry Ahmed <[email protected]>
> ---
> arch/arm64/kvm/mmu.c | 35 +++++++++++++++++++++++++++++++----
> 1 file changed, 31 insertions(+), 4 deletions(-)
>
> diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
> index 53ae2c0640bc..fc5030307cce 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);
Sorry I didn't say it last time around, would now be a good time to
clean up the funky sign convention of kvm_mod_used_mmu_pages()? Or limit
the funk to just x86 :)
--
Thanks,
Oliver