Linux IOMMU Development
 help / color / mirror / Atom feed
From: Sean Christopherson <seanjc@google.com>
To: Sean Christopherson <seanjc@google.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	 Joerg Roedel <joro@8bytes.org>,
	David Woodhouse <dwmw2@infradead.org>,
	 Lu Baolu <baolu.lu@linux.intel.com>
Cc: kvm@vger.kernel.org, iommu@lists.linux.dev,
	linux-kernel@vger.kernel.org,  Sairaj Kodilkar <sarunkod@amd.com>,
	Vasant Hegde <vasant.hegde@amd.com>,
	 Maxim Levitsky <mlevitsk@redhat.com>,
	Joao Martins <joao.m.martins@oracle.com>,
	 Francesco Lavra <francescolavra.fl@gmail.com>,
	David Matlack <dmatlack@google.com>
Subject: [PATCH v2 57/59] KVM: SVM: Consolidate IRTE update when toggling AVIC on/off
Date: Thu, 22 May 2025 18:00:02 -0700	[thread overview]
Message-ID: <20250523010004.3240643-58-seanjc@google.com> (raw)
In-Reply-To: <20250523010004.3240643-1-seanjc@google.com>

Fold the IRTE modification logic in avic_refresh_apicv_exec_ctrl() into
__avic_vcpu_{load,put}(), and add a param to the helpers to communicate
whether or not AVIC is being toggled, i.e. if IRTE needs a "full" update,
or just a quick update to set the CPU and IsRun.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/svm/avic.c | 85 ++++++++++++++++++++++-------------------
 1 file changed, 46 insertions(+), 39 deletions(-)

diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
index 1e6e5d1f6b4e..2e47559a4134 100644
--- a/arch/x86/kvm/svm/avic.c
+++ b/arch/x86/kvm/svm/avic.c
@@ -810,7 +810,28 @@ int avic_pi_update_irte(struct kvm_kernel_irqfd *irqfd, struct kvm *kvm,
 	return irq_set_vcpu_affinity(host_irq, NULL);
 }
 
-static void avic_update_iommu_vcpu_affinity(struct kvm_vcpu *vcpu, int cpu)
+enum avic_vcpu_action {
+	/*
+	 * There is no need to differentiate between activate and deactivate,
+	 * as KVM only refreshes AVIC state when the vCPU is scheduled in and
+	 * isn't blocking, i.e. the pCPU must always be (in)valid when AVIC is
+	 * being (de)activated.
+	 */
+	AVIC_TOGGLE_ON_OFF	= BIT(0),
+	AVIC_ACTIVATE		= AVIC_TOGGLE_ON_OFF,
+	AVIC_DEACTIVATE		= AVIC_TOGGLE_ON_OFF,
+
+	/*
+	 * No unique action is required to deal with a vCPU that stops/starts
+	 * running, as IRTEs are configured to generate GALog interrupts at all
+	 * times.
+	 */
+	AVIC_START_RUNNING	= 0,
+	AVIC_STOP_RUNNING	= 0,
+};
+
+static void avic_update_iommu_vcpu_affinity(struct kvm_vcpu *vcpu, int cpu,
+					    enum avic_vcpu_action action)
 {
 	struct vcpu_svm *svm = to_svm(vcpu);
 	struct kvm_kernel_irqfd *irqfd;
@@ -824,11 +845,20 @@ static void avic_update_iommu_vcpu_affinity(struct kvm_vcpu *vcpu, int cpu)
 	if (list_empty(&svm->ir_list))
 		return;
 
-	list_for_each_entry(irqfd, &svm->ir_list, vcpu_list)
-		WARN_ON_ONCE(amd_iommu_update_ga(cpu, irqfd->irq_bypass_data));
+	list_for_each_entry(irqfd, &svm->ir_list, vcpu_list) {
+		void *data = irqfd->irq_bypass_data;
+
+		if (!(action & AVIC_TOGGLE_ON_OFF))
+			WARN_ON_ONCE(amd_iommu_update_ga(cpu, data));
+		else if (cpu >= 0)
+			WARN_ON_ONCE(amd_iommu_activate_guest_mode(data, cpu));
+		else
+			WARN_ON_ONCE(amd_iommu_deactivate_guest_mode(data));
+	}
 }
 
-static void __avic_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
+static void __avic_vcpu_load(struct kvm_vcpu *vcpu, int cpu,
+			     enum avic_vcpu_action action)
 {
 	struct kvm_svm *kvm_svm = to_kvm_svm(vcpu->kvm);
 	int h_physical_id = kvm_cpu_get_apicid(cpu);
@@ -873,7 +903,7 @@ static void __avic_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 
 	WRITE_ONCE(kvm_svm->avic_physical_id_table[vcpu->vcpu_id], entry);
 
-	avic_update_iommu_vcpu_affinity(vcpu, h_physical_id);
+	avic_update_iommu_vcpu_affinity(vcpu, h_physical_id, action);
 
 	spin_unlock_irqrestore(&svm->ir_list_lock, flags);
 }
@@ -890,10 +920,10 @@ void avic_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 	if (kvm_vcpu_is_blocking(vcpu))
 		return;
 
-	__avic_vcpu_load(vcpu, cpu);
+	__avic_vcpu_load(vcpu, cpu, AVIC_START_RUNNING);
 }
 
-static void __avic_vcpu_put(struct kvm_vcpu *vcpu)
+static void __avic_vcpu_put(struct kvm_vcpu *vcpu, enum avic_vcpu_action action)
 {
 	struct kvm_svm *kvm_svm = to_kvm_svm(vcpu->kvm);
 	struct vcpu_svm *svm = to_svm(vcpu);
@@ -915,7 +945,7 @@ static void __avic_vcpu_put(struct kvm_vcpu *vcpu)
 	 */
 	spin_lock_irqsave(&svm->ir_list_lock, flags);
 
-	avic_update_iommu_vcpu_affinity(vcpu, -1);
+	avic_update_iommu_vcpu_affinity(vcpu, -1, action);
 
 	entry &= ~AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK;
 	svm->avic_physical_id_entry = entry;
@@ -941,7 +971,7 @@ void avic_vcpu_put(struct kvm_vcpu *vcpu)
 	if (!(entry & AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK))
 		return;
 
-	__avic_vcpu_put(vcpu);
+	__avic_vcpu_put(vcpu, AVIC_STOP_RUNNING);
 }
 
 void avic_refresh_virtual_apic_mode(struct kvm_vcpu *vcpu)
@@ -970,41 +1000,18 @@ void avic_refresh_virtual_apic_mode(struct kvm_vcpu *vcpu)
 
 void avic_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu)
 {
-	bool activated = kvm_vcpu_apicv_active(vcpu);
-	int apic_id = kvm_cpu_get_apicid(vcpu->cpu);
-	struct vcpu_svm *svm = to_svm(vcpu);
-	struct kvm_kernel_irqfd *irqfd;
-	unsigned long flags;
-
 	if (!enable_apicv)
 		return;
 
+	/* APICv should only be toggled on/off while the vCPU is running. */
+	WARN_ON_ONCE(kvm_vcpu_is_blocking(vcpu));
+
 	avic_refresh_virtual_apic_mode(vcpu);
 
-	if (activated)
-		__avic_vcpu_load(vcpu, vcpu->cpu);
+	if (kvm_vcpu_apicv_active(vcpu))
+		__avic_vcpu_load(vcpu, vcpu->cpu, AVIC_ACTIVATE);
 	else
-		__avic_vcpu_put(vcpu);
-
-	/*
-	 * Here, we go through the per-vcpu ir_list to update all existing
-	 * interrupt remapping table entry targeting this vcpu.
-	 */
-	spin_lock_irqsave(&svm->ir_list_lock, flags);
-
-	if (list_empty(&svm->ir_list))
-		goto out;
-
-	list_for_each_entry(irqfd, &svm->ir_list, vcpu_list) {
-		void *data = irqfd->irq_bypass_data;
-
-		if (activated)
-			WARN_ON_ONCE(amd_iommu_activate_guest_mode(data, apic_id));
-		else
-			WARN_ON_ONCE(amd_iommu_deactivate_guest_mode(data));
-	}
-out:
-	spin_unlock_irqrestore(&svm->ir_list_lock, flags);
+		__avic_vcpu_put(vcpu, AVIC_DEACTIVATE);
 }
 
 void avic_vcpu_blocking(struct kvm_vcpu *vcpu)
@@ -1030,7 +1037,7 @@ void avic_vcpu_blocking(struct kvm_vcpu *vcpu)
 	 * CPU and cause noisy neighbor problems if the VM is sending interrupts
 	 * to the vCPU while it's scheduled out.
 	 */
-	avic_vcpu_put(vcpu);
+	__avic_vcpu_put(vcpu, AVIC_STOP_RUNNING);
 }
 
 void avic_vcpu_unblocking(struct kvm_vcpu *vcpu)
-- 
2.49.0.1151.ga128411c76-goog


  parent reply	other threads:[~2025-05-23  1:01 UTC|newest]

Thread overview: 68+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-05-23  0:59 [PATCH v2 00/59] KVM: iommu: Overhaul device posted IRQs support Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 01/59] KVM: x86: Pass new routing entries and irqfd when updating IRTEs Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 02/59] KVM: SVM: Track per-vCPU IRTEs using kvm_kernel_irqfd structure Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 03/59] KVM: SVM: Delete IRTE link from previous vCPU before setting new IRTE Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 04/59] iommu/amd: KVM: SVM: Delete now-unused cached/previous GA tag fields Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 05/59] KVM: SVM: Delete IRTE link from previous vCPU irrespective of new routing Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 06/59] KVM: SVM: Drop pointless masking of default APIC base when setting V_APIC_BAR Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 07/59] KVM: SVM: Drop pointless masking of kernel page pa's with AVIC HPA masks Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 08/59] KVM: SVM: Add helper to deduplicate code for getting AVIC backing page Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 09/59] KVM: SVM: Drop vcpu_svm's pointless avic_backing_page field Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 10/59] KVM: SVM: Inhibit AVIC if ID is too big instead of rejecting vCPU creation Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 11/59] KVM: SVM: Drop redundant check in AVIC code on ID during " Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 12/59] KVM: SVM: Track AVIC tables as natively sized pointers, not "struct pages" Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 13/59] KVM: SVM: Drop superfluous "cache" of AVIC Physical ID entry pointer Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 14/59] KVM: VMX: Move enable_ipiv knob to common x86 Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 15/59] KVM: SVM: Add enable_ipiv param, never set IsRunning if disabled Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 16/59] KVM: SVM: Disable (x2)AVIC IPI virtualization if CPU has erratum #1235 Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 17/59] KVM: VMX: Suppress PI notifications whenever the vCPU is put Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 18/59] KVM: SVM: Add a comment to explain why avic_vcpu_blocking() ignores IRQ blocking Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 19/59] iommu/amd: KVM: SVM: Use pi_desc_addr to derive ga_root_ptr Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 20/59] iommu/amd: KVM: SVM: Pass NULL @vcpu_info to indicate "not guest mode" Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 21/59] KVM: SVM: Stop walking list of routing table entries when updating IRTE Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 22/59] KVM: VMX: " Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 23/59] KVM: SVM: Extract SVM specific code out of get_pi_vcpu_info() Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 24/59] KVM: x86: Move IRQ routing/delivery APIs from x86.c => irq.c Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 25/59] KVM: x86: Nullify irqfd->producer after updating IRTEs Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 26/59] KVM: x86: Dedup AVIC vs. PI code for identifying target vCPU Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 27/59] KVM: x86: Move posted interrupt tracepoint to common code Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 28/59] KVM: SVM: Clean up return handling in avic_pi_update_irte() Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 29/59] iommu: KVM: Split "struct vcpu_data" into separate AMD vs. Intel structs Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 30/59] KVM: Don't WARN if updating IRQ bypass route fails Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 31/59] KVM: Fold kvm_arch_irqfd_route_changed() into kvm_arch_update_irqfd_routing() Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 32/59] KVM: x86: Track irq_bypass_vcpu in common x86 code Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 33/59] KVM: x86: Skip IOMMU IRTE updates if there's no old or new vCPU being targeted Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 34/59] KVM: x86: Don't update IRTE entries when old and new routes were !MSI Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 35/59] KVM: SVM: Revert IRTE to legacy mode if IOMMU doesn't provide IR metadata Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 36/59] KVM: SVM: Take and hold ir_list_lock across IRTE updates in IOMMU Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 37/59] iommu/amd: Document which IRTE fields amd_iommu_update_ga() can modify Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 38/59] iommu/amd: KVM: SVM: Infer IsRun from validity of pCPU destination Sean Christopherson
2025-05-30 10:13   ` Sairaj Kodilkar
2025-06-02 21:59     ` Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 39/59] iommu/amd: Factor out helper for manipulating IRTE GA/CPU info Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 40/59] iommu/amd: KVM: SVM: Set pCPU info in IRTE when setting vCPU affinity Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 41/59] iommu/amd: KVM: SVM: Add IRTE metadata to affined vCPU's list if AVIC is inhibited Sean Christopherson
2025-05-30 10:06   ` Sairaj Kodilkar
2025-06-02 22:26     ` Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 42/59] KVM: SVM: Don't check for assigned device(s) when updating affinity Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 43/59] KVM: SVM: Don't check for assigned device(s) when activating AVIC Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 44/59] KVM: SVM: WARN if (de)activating guest mode in IOMMU fails Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 45/59] KVM: SVM: Process all IRTEs on affinity change even if one update fails Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 46/59] KVM: SVM: WARN if updating IRTE GA fields in IOMMU fails Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 47/59] KVM: x86: Drop superfluous "has assigned device" check in kvm_pi_update_irte() Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 48/59] KVM: x86: WARN if IRQ bypass isn't supported " Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 49/59] KVM: x86: WARN if IRQ bypass routing is updated without in-kernel local APIC Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 50/59] KVM: SVM: WARN if ir_list is non-empty at vCPU free Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 51/59] KVM: x86: Decouple device assignment from IRQ bypass Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 52/59] KVM: VMX: WARN if VT-d Posted IRQs aren't possible when starting " Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 53/59] KVM: SVM: Use vcpu_idx, not vcpu_id, for GA log tag/metadata Sean Christopherson
2025-05-23  0:59 ` [PATCH v2 54/59] iommu/amd: WARN if KVM calls GA IRTE helpers without virtual APIC support Sean Christopherson
2025-05-23  1:00 ` [PATCH v2 55/59] KVM: SVM: Fold avic_set_pi_irte_mode() into its sole caller Sean Christopherson
2025-05-23  1:00 ` [PATCH v2 56/59] KVM: SVM: Don't check vCPU's blocking status when toggling AVIC on/off Sean Christopherson
2025-05-23  1:00 ` Sean Christopherson [this message]
2025-05-23  1:00 ` [PATCH v2 58/59] iommu/amd: KVM: SVM: Allow KVM to control need for GA log interrupts Sean Christopherson
2025-05-23  1:00 ` [PATCH v2 59/59] KVM: SVM: Generate GA log IRQs only if the associated vCPUs is blocking Sean Christopherson
2025-06-04 17:11 ` [PATCH v2 00/59] KVM: iommu: Overhaul device posted IRQs support Paolo Bonzini
2025-06-09 12:20 ` Sairaj Kodilkar
2025-06-09 14:34   ` [PATCH " Sean Christopherson
2025-06-12 11:03     ` Sairaj Kodilkar

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=20250523010004.3240643-58-seanjc@google.com \
    --to=seanjc@google.com \
    --cc=baolu.lu@linux.intel.com \
    --cc=dmatlack@google.com \
    --cc=dwmw2@infradead.org \
    --cc=francescolavra.fl@gmail.com \
    --cc=iommu@lists.linux.dev \
    --cc=joao.m.martins@oracle.com \
    --cc=joro@8bytes.org \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mlevitsk@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=sarunkod@amd.com \
    --cc=vasant.hegde@amd.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