mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Paolo Bonzini <pbonzini@redhat.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: isaku.yamahata@intel.com, seanjc@google.com,
	binbin.wu@linux.intel.com, xiaoyao.li@intel.com
Subject: [PATCH v5 4/7] KVM: x86/mmu: Account pf_{fixed,emulate,spurious} in callers of "do page fault"
Date: Wed, 10 Jul 2024 13:40:28 -0400	[thread overview]
Message-ID: <20240710174031.312055-5-pbonzini@redhat.com> (raw)
In-Reply-To: <20240710174031.312055-1-pbonzini@redhat.com>

From: Sean Christopherson <seanjc@google.com>

Move the accounting of the result of kvm_mmu_do_page_fault() to its
callers, as only pf_fixed is common to guest page faults and async #PFs,
and upcoming support KVM_PRE_FAULT_MEMORY won't bump _any_ stats.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/kvm/mmu/mmu.c          | 19 ++++++++++++++++++-
 arch/x86/kvm/mmu/mmu_internal.h | 13 -------------
 2 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index aa437aacf55f..8c2c5c0afba1 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4291,7 +4291,16 @@ void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu, struct kvm_async_pf *work)
 	      work->arch.cr3 != kvm_mmu_get_guest_pgd(vcpu, vcpu->arch.mmu))
 		return;
 
-	kvm_mmu_do_page_fault(vcpu, work->cr2_or_gpa, work->arch.error_code, true, NULL);
+	r = kvm_mmu_do_page_fault(vcpu, work->cr2_or_gpa, work->arch.error_code,
+				  true, NULL);
+
+	/*
+	 * Account fixed page faults, otherwise they'll never be counted, but
+	 * ignore stats for all other return times.  Page-ready "faults" aren't
+	 * truly spurious and never trigger emulation
+	 */
+	if (r == RET_PF_FIXED)
+		vcpu->stat.pf_fixed++;
 }
 
 static inline u8 kvm_max_level_for_order(int order)
@@ -5935,6 +5944,14 @@ int noinline kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 err
 
 	if (r < 0)
 		return r;
+
+	if (r == RET_PF_FIXED)
+		vcpu->stat.pf_fixed++;
+	else if (r == RET_PF_EMULATE)
+		vcpu->stat.pf_emulate++;
+	else if (r == RET_PF_SPURIOUS)
+		vcpu->stat.pf_spurious++;
+
 	if (r != RET_PF_EMULATE)
 		return 1;
 
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index 8efd31b3856b..444f55a5eed7 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -337,19 +337,6 @@ static inline int kvm_mmu_do_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
 	if (fault.write_fault_to_shadow_pgtable && emulation_type)
 		*emulation_type |= EMULTYPE_WRITE_PF_TO_SP;
 
-	/*
-	 * Similar to above, prefetch faults aren't truly spurious, and the
-	 * async #PF path doesn't do emulation.  Do count faults that are fixed
-	 * by the async #PF handler though, otherwise they'll never be counted.
-	 */
-	if (r == RET_PF_FIXED)
-		vcpu->stat.pf_fixed++;
-	else if (prefetch)
-		;
-	else if (r == RET_PF_EMULATE)
-		vcpu->stat.pf_emulate++;
-	else if (r == RET_PF_SPURIOUS)
-		vcpu->stat.pf_spurious++;
 	return r;
 }
 
-- 
2.43.0



  parent reply	other threads:[~2024-07-10 17:40 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-07-10 17:40 [PATCH v5 0/7] KVM: Guest Memory Pre-Population API Paolo Bonzini
2024-07-10 17:40 ` [PATCH v5 1/7] KVM: Document KVM_PRE_FAULT_MEMORY ioctl Paolo Bonzini
2024-07-10 17:40 ` [PATCH v5 2/7] KVM: Add KVM_PRE_FAULT_MEMORY vcpu ioctl to pre-populate guest memory Paolo Bonzini
2024-07-10 20:46   ` Anish Moorthy
2024-07-10 21:56     ` Sean Christopherson
2024-07-10 22:04       ` Paolo Bonzini
2024-07-10 17:40 ` [PATCH v5 3/7] KVM: x86/mmu: Bump pf_taken stat only in the "real" page fault handler Paolo Bonzini
2024-07-10 17:40 ` Paolo Bonzini [this message]
2024-07-10 17:40 ` [PATCH v5 5/7] KVM: x86/mmu: Make kvm_mmu_do_page_fault() return mapped level Paolo Bonzini
2024-07-10 17:40 ` [PATCH v5 6/7] KVM: x86: Implement kvm_arch_vcpu_pre_fault_memory() Paolo Bonzini
2024-07-11  5:36   ` Binbin Wu
2024-07-11  8:30     ` Paolo Bonzini
2024-07-10 17:40 ` [PATCH v5 7/7] KVM: selftests: x86: Add test for KVM_PRE_FAULT_MEMORY Paolo Bonzini

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20240710174031.312055-5-pbonzini@redhat.com \
    --to=pbonzini@redhat.com \
    --cc=binbin.wu@linux.intel.com \
    --cc=isaku.yamahata@intel.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=seanjc@google.com \
    --cc=xiaoyao.li@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®