Currently, during the operations such as a hugepage collapse,
KVM would flush the entire VM's context using 'vmalls12e1is'
TLBI operation. Specifically, if the VM is faulting on many
hugepages (say after dirty-logging), it creates a performance
penalty for the guest whose pages have already been faulted
earlier as they would have to refill their TLBs again.
Instead, leverage kvm_tlb_flush_vmid_range() for table entries.
If the system supports it, only the required range will be
flushed. Else, it'll fallback to the previous mechanism.
Signed-off-by: Raghavendra Rao Ananta <[email protected]>
Reviewed-by: Gavin Shan <[email protected]>
Reviewed-by: Shaoqin Huang <[email protected]>
---
arch/arm64/kvm/hyp/pgtable.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c
index 5d14d5d5819a..5ef098af1736 100644
--- a/arch/arm64/kvm/hyp/pgtable.c
+++ b/arch/arm64/kvm/hyp/pgtable.c
@@ -806,7 +806,8 @@ static bool stage2_try_break_pte(const struct kvm_pgtable_visit_ctx *ctx,
* evicted pte value (if any).
*/
if (kvm_pte_table(ctx->old, ctx->level))
- kvm_call_hyp(__kvm_tlb_flush_vmid, mmu);
+ kvm_tlb_flush_vmid_range(mmu, ctx->addr,
+ kvm_granule_size(ctx->level));
else if (kvm_pte_valid(ctx->old))
kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, mmu,
ctx->addr, ctx->level);
--
2.41.0.487.g6d72f3e995-goog