[PATCH 7/8] KVM: MMU: Push trace_kvm_age_page() intokvm_age_rmapp()

From: Takuya Yoshikawa
Date: Mon Jul 02 2012 - 04:59:01 EST


This restricts the tracing to page aging and makes it possible to
optimize kvm_handle_hva_range() further in the following patch.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@xxxxxxxxxxxxx>
---
arch/x86/kvm/mmu.c | 23 ++++++++++-------------
1 files changed, 10 insertions(+), 13 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index bf8d50e..3082199 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1193,8 +1193,7 @@ static int kvm_handle_hva_range(struct kvm *kvm,
unsigned long data))
{
int j;
- int ret;
- int retval = 0;
+ int ret = 0;
struct kvm_memslots *slots;
struct kvm_memory_slot *memslot;

@@ -1217,8 +1216,6 @@ static int kvm_handle_hva_range(struct kvm *kvm,
gfn_end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, memslot);

for (; gfn < gfn_end; ++gfn) {
- ret = 0;
-
for (j = PT_PAGE_TABLE_LEVEL;
j < PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES; ++j) {
unsigned long *rmapp;
@@ -1226,14 +1223,10 @@ static int kvm_handle_hva_range(struct kvm *kvm,
rmapp = __gfn_to_rmap(gfn, j, memslot);
ret |= handler(kvm, rmapp, memslot, data);
}
- trace_kvm_age_page(memslot->userspace_addr +
- (gfn - memslot->base_gfn) * PAGE_SIZE,
- memslot, ret);
- retval |= ret;
}
}

- return retval;
+ return ret;
}

static int kvm_handle_hva(struct kvm *kvm, unsigned long hva,
@@ -1275,8 +1268,10 @@ static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp,
* This has some overhead, but not as much as the cost of swapping
* out actively used pages or breaking up actively used hugepages.
*/
- if (!shadow_accessed_mask)
- return kvm_unmap_rmapp(kvm, rmapp, slot, data);
+ if (!shadow_accessed_mask) {
+ young = kvm_unmap_rmapp(kvm, rmapp, slot, data);
+ goto out;
+ }

for (sptep = rmap_get_first(*rmapp, &iter); sptep;
sptep = rmap_get_next(&iter)) {
@@ -1288,7 +1283,9 @@ static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp,
(unsigned long *)sptep);
}
}
-
+out:
+ /* @data has hva passed to kvm_age_hva(). */
+ trace_kvm_age_page(data, slot, young);
return young;
}

@@ -1337,7 +1334,7 @@ static void rmap_recycle(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn)

int kvm_age_hva(struct kvm *kvm, unsigned long hva)
{
- return kvm_handle_hva(kvm, hva, 0, kvm_age_rmapp);
+ return kvm_handle_hva(kvm, hva, hva, kvm_age_rmapp);
}

int kvm_test_age_hva(struct kvm *kvm, unsigned long hva)
--
1.7.5.4

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