diff mbox series

[1/2] kvm: x86/mmu: Add existing trace points to TDP MMU

Message ID 20201027175944.1183301-1-bgardon@google.com (mailing list archive)
State New, archived
Headers show
Series [1/2] kvm: x86/mmu: Add existing trace points to TDP MMU | expand

Commit Message

Ben Gardon Oct. 27, 2020, 5:59 p.m. UTC
The TDP MMU was initially implemented without some of the usual
tracepoints found in mmu.c. Correct this discrepancy by adding the
missing trace points to the TDP MMU.

Tested: ran the demand paging selftest on an Intel Skylake machine with
	all the trace points used by the TDP MMU enabled and observed
	them firing with expected values.

This patch can be viewed in Gerrit at:
https://linux-review.googlesource.com/c/virt/kvm/kvm/+/3812

Signed-off-by: Ben Gardon <bgardon@google.com>
---
 arch/x86/kvm/mmu/tdp_mmu.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

Comments

Ben Gardon Nov. 16, 2020, 7:15 p.m. UTC | #1
On Tue, Oct 27, 2020 at 10:59 AM Ben Gardon <bgardon@google.com> wrote:
>
> The TDP MMU was initially implemented without some of the usual
> tracepoints found in mmu.c. Correct this discrepancy by adding the
> missing trace points to the TDP MMU.
>
> Tested: ran the demand paging selftest on an Intel Skylake machine with
>         all the trace points used by the TDP MMU enabled and observed
>         them firing with expected values.
>
> This patch can be viewed in Gerrit at:
> https://linux-review.googlesource.com/c/virt/kvm/kvm/+/3812
>
> Signed-off-by: Ben Gardon <bgardon@google.com>
> ---
>  arch/x86/kvm/mmu/tdp_mmu.c | 12 +++++++++++-
>  1 file changed, 11 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
> index 27e381c9da6c2..047e2d966abef 100644
> --- a/arch/x86/kvm/mmu/tdp_mmu.c
> +++ b/arch/x86/kvm/mmu/tdp_mmu.c
> @@ -7,6 +7,8 @@
>  #include "tdp_mmu.h"
>  #include "spte.h"
>
> +#include <trace/events/kvm.h>
> +
>  #ifdef CONFIG_X86_64
>  static bool __read_mostly tdp_mmu_enabled = false;
>  module_param_named(tdp_mmu, tdp_mmu_enabled, bool, 0644);
> @@ -101,6 +103,8 @@ static struct kvm_mmu_page *alloc_tdp_mmu_page(struct kvm_vcpu *vcpu, gfn_t gfn,
>         sp->gfn = gfn;
>         sp->tdp_mmu_page = true;
>
> +       trace_kvm_mmu_get_page(sp, true);
> +
>         return sp;
>  }
>
> @@ -271,6 +275,8 @@ static void __handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn,
>                 pt = spte_to_child_pt(old_spte, level);
>                 sp = sptep_to_sp(pt);
>
> +               trace_kvm_mmu_prepare_zap_page(sp);
> +
>                 list_del(&sp->link);
>
>                 if (sp->lpage_disallowed)
> @@ -473,11 +479,13 @@ static int tdp_mmu_map_handle_target_level(struct kvm_vcpu *vcpu, int write,
>         if (unlikely(is_noslot_pfn(pfn))) {
>                 new_spte = make_mmio_spte(vcpu, iter->gfn, ACC_ALL);
>                 trace_mark_mmio_spte(iter->sptep, iter->gfn, new_spte);
> -       } else
> +       } else {
>                 make_spte_ret = make_spte(vcpu, ACC_ALL, iter->level, iter->gfn,
>                                          pfn, iter->old_spte, prefault, true,
>                                          map_writable, !shadow_accessed_mask,
>                                          &new_spte);
> +               trace_kvm_mmu_set_spte(iter->level, iter->gfn, iter->sptep);
> +       }
>
>         if (new_spte == iter->old_spte)
>                 ret = RET_PF_SPURIOUS;
> @@ -691,6 +699,8 @@ static int age_gfn_range(struct kvm *kvm, struct kvm_memory_slot *slot,
>
>                 tdp_mmu_set_spte_no_acc_track(kvm, &iter, new_spte);
>                 young = 1;
> +
> +               trace_kvm_age_page(iter.gfn, iter.level, slot, young);
>         }
>
>         return young;
> --
> 2.29.0.rc2.309.g374f81d7ae-goog
>

If anyone has time to review this short series, I'd appreciate it. I
don't want these to get lost in the shuffle.
Thanks!
Paolo Bonzini Nov. 16, 2020, 7:25 p.m. UTC | #2
On 16/11/20 20:15, Ben Gardon wrote:
> If anyone has time to review this short series, I'd appreciate it. I
> don't want these to get lost in the shuffle.
> Thanks!

Yup, it's on the list. :)

Paolo
Paolo Bonzini Nov. 17, 2020, 11:04 a.m. UTC | #3
On 16/11/20 20:25, Paolo Bonzini wrote:
> On 16/11/20 20:15, Ben Gardon wrote:
>> If anyone has time to review this short series, I'd appreciate it. I
>> don't want these to get lost in the shuffle.
>> Thanks!
> 
> Yup, it's on the list. :)

Queued, thanks.

Paolo
diff mbox series

Patch

diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 27e381c9da6c2..047e2d966abef 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -7,6 +7,8 @@ 
 #include "tdp_mmu.h"
 #include "spte.h"
 
+#include <trace/events/kvm.h>
+
 #ifdef CONFIG_X86_64
 static bool __read_mostly tdp_mmu_enabled = false;
 module_param_named(tdp_mmu, tdp_mmu_enabled, bool, 0644);
@@ -101,6 +103,8 @@  static struct kvm_mmu_page *alloc_tdp_mmu_page(struct kvm_vcpu *vcpu, gfn_t gfn,
 	sp->gfn = gfn;
 	sp->tdp_mmu_page = true;
 
+	trace_kvm_mmu_get_page(sp, true);
+
 	return sp;
 }
 
@@ -271,6 +275,8 @@  static void __handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn,
 		pt = spte_to_child_pt(old_spte, level);
 		sp = sptep_to_sp(pt);
 
+		trace_kvm_mmu_prepare_zap_page(sp);
+
 		list_del(&sp->link);
 
 		if (sp->lpage_disallowed)
@@ -473,11 +479,13 @@  static int tdp_mmu_map_handle_target_level(struct kvm_vcpu *vcpu, int write,
 	if (unlikely(is_noslot_pfn(pfn))) {
 		new_spte = make_mmio_spte(vcpu, iter->gfn, ACC_ALL);
 		trace_mark_mmio_spte(iter->sptep, iter->gfn, new_spte);
-	} else
+	} else {
 		make_spte_ret = make_spte(vcpu, ACC_ALL, iter->level, iter->gfn,
 					 pfn, iter->old_spte, prefault, true,
 					 map_writable, !shadow_accessed_mask,
 					 &new_spte);
+		trace_kvm_mmu_set_spte(iter->level, iter->gfn, iter->sptep);
+	}
 
 	if (new_spte == iter->old_spte)
 		ret = RET_PF_SPURIOUS;
@@ -691,6 +699,8 @@  static int age_gfn_range(struct kvm *kvm, struct kvm_memory_slot *slot,
 
 		tdp_mmu_set_spte_no_acc_track(kvm, &iter, new_spte);
 		young = 1;
+
+		trace_kvm_age_page(iter.gfn, iter.level, slot, young);
 	}
 
 	return young;