From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shaoqin Huang Date: Tue, 18 Jul 2023 19:17:26 +0800 Subject: [PATCH v6 10/11] KVM: arm64: Invalidate the table entries upon a range In-Reply-To: <20230715005405.3689586-11-rananta@google.com> References: <20230715005405.3689586-1-rananta@google.com> <20230715005405.3689586-11-rananta@google.com> Message-ID: List-Id: To: kvm-riscv@lists.infradead.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On 7/15/23 08:54, Raghavendra Rao Ananta wrote: > 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 > Reviewed-by: Gavin Shan Reviewed-by: Shaoqin Huang > --- > 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); -- Shaoqin