rmap_remove() would remove the sptep after locating the correct
rmap_head. While in several cases, the caller has already known the
correct rmap_head.
This patch introduce drop_spte_fast() which remove sptep directly
from rmap_head by pte_list_remove().
Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxx>
---
arch/x86/kvm/mmu.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 371d200ffd4a..9fa77aa24fc7 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1412,6 +1412,13 @@ static u64 *rmap_get_next(struct rmap_iterator *iter)
for (_spte_ = rmap_get_first(_rmap_head_, _iter_); \
_spte_; _spte_ = rmap_get_next(_iter_))
+/* In case caller knows the rmap_head, just remove it by pte_list_remove() */
+static void drop_spte_fast(struct kvm_rmap_head *rmap_head, u64 *sptep)
+{
+ if (mmu_spte_clear_track_bits(sptep))
+ pte_list_remove(sptep, rmap_head);
+}
+
static void drop_spte(struct kvm *kvm, u64 *sptep)
{
if (mmu_spte_clear_track_bits(sptep))
@@ -1669,7 +1676,7 @@ static bool kvm_zap_rmapp(struct kvm *kvm, struct kvm_rmap_head *rmap_head)
while ((sptep = rmap_get_first(rmap_head, &iter))) {
rmap_printk("%s: spte %p %llx.\n", __func__, sptep, *sptep);
- drop_spte(kvm, sptep);
+ drop_spte_fast(rmap_head, sptep);
flush = true;
}
@@ -1705,7 +1712,7 @@ static int kvm_set_pte_rmapp(struct kvm *kvm, struct kvm_rmap_head *rmap_head,
need_flush = 1;
if (pte_write(*ptep)) {
- drop_spte(kvm, sptep);
+ drop_spte_fast(rmap_head, sptep);
goto restart;
} else {
new_spte = *sptep & ~PT64_BASE_ADDR_MASK;
@@ -5598,7 +5605,7 @@ static bool kvm_mmu_zap_collapsible_spte(struct kvm *kvm,
if (sp->role.direct &&
!kvm_is_reserved_pfn(pfn) &&
PageTransCompoundMap(pfn_to_page(pfn))) {
- drop_spte(kvm, sptep);
+ drop_spte_fast(rmap_head, sptep);
need_tlb_flush = 1;
goto restart;
}
--
2.15.1
