From: Yosry Ahmed <yosry@kernel.org>
To: Sean Christopherson <seanjc@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>,
Jim Mattson <jmattson@google.com>,
Dapeng Mi <dapeng1.mi@linux.intel.com>,
Sandipan Das <sandipan.das@amd.com>,
Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@redhat.com>,
Arnaldo Carvalho de Melo <acme@kernel.org>,
Namhyung Kim <namhyung@kernel.org>,
Mark Rutland <mark.rutland@arm.com>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
Yosry Ahmed <yosry@kernel.org>
Subject: [PATCH v6 06/16] KVM: x86/pmu: Do a single atomic OR when reprogramming counters
Date: Wed, 6 May 2026 01:57:22 +0000 [thread overview]
Message-ID: <20260506015733.1671124-7-yosry@kernel.org> (raw)
In-Reply-To: <20260506015733.1671124-1-yosry@kernel.org>
Do a single atomic OR using the atomic overlay of reprogram_pmi bitmask,
instead of one atomic set_bit() call per counter.
Signed-off-by: Yosry Ahmed <yosry@kernel.org>
---
arch/x86/kvm/pmu.h | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)
diff --git a/arch/x86/kvm/pmu.h b/arch/x86/kvm/pmu.h
index f8286067722b0..0e99022168a85 100644
--- a/arch/x86/kvm/pmu.h
+++ b/arch/x86/kvm/pmu.h
@@ -213,13 +213,10 @@ static inline void kvm_pmu_request_counter_reprogram(struct kvm_pmc *pmc)
static inline void kvm_pmu_request_counters_reprogram(struct kvm_pmu *pmu,
u64 counters)
{
- int bit;
-
if (!counters)
return;
- for_each_set_bit(bit, (unsigned long *)&counters, X86_PMC_IDX_MAX)
- set_bit(bit, pmu->reprogram_pmi);
+ atomic64_or(counters, &pmu->__reprogram_pmi);
kvm_make_request(KVM_REQ_PMU, pmu_to_vcpu(pmu));
}
--
2.54.0.545.g6539524ca2-goog
next prev parent reply other threads:[~2026-05-06 1:58 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-05-06 1:57 [PATCH v6 00/16] Yosry Ahmed
2026-05-06 1:57 ` [PATCH v6 01/16] KVM: nSVM: Stop leaking single-stepping on VMRUN into L2 Yosry Ahmed
2026-05-06 1:57 ` [PATCH v6 02/16] KVM: nSVM: Bail early out of VMRUN emulation if advancing RIP fails Yosry Ahmed
2026-05-06 1:57 ` [PATCH v6 03/16] KVM: nSVM: Move VMRUN instruction retirement after entering guest mode Yosry Ahmed
2026-05-06 1:57 ` [PATCH v6 04/16] KVM: x86: Move enable_pmu/enable_mediated_pmu to pmu.h and pmu.c Yosry Ahmed
2026-05-06 1:57 ` [PATCH v6 05/16] KVM: x86/pmu: Rename reprogram_counters() to clarify usage Yosry Ahmed
2026-05-06 1:57 ` Yosry Ahmed [this message]
2026-05-06 1:57 ` [PATCH v6 07/16] KVM: x86/pmu: Check mediated PMU counter enablement before event filters Yosry Ahmed
2026-05-06 1:57 ` [PATCH v6 08/16] KVM: x86/pmu: Add support for KVM_X86_PMU_OP_OPTIONAL_RET0 Yosry Ahmed
2026-05-06 1:57 ` [PATCH v6 09/16] KVM: x86/pmu: Disable counters based on Host-Only/Guest-Only bits in SVM Yosry Ahmed
2026-05-06 1:57 ` [PATCH v6 10/16] KVM: x86/pmu: Track mediated PMU counters with mode-specific enables Yosry Ahmed
2026-05-06 1:57 ` [PATCH v6 11/16] KVM: x86/pmu: Reprogram Host/Guest-Only counters on nested transitions Yosry Ahmed
2026-05-06 1:57 ` [PATCH v6 12/16] KVM: x86/pmu: Allow Host-Only/Guest-Only bits with nSVM and mediated PMU Yosry Ahmed
2026-05-06 1:57 ` [PATCH v6 13/16] KVM: selftests: Refactor allocating guest stack into a helper Yosry Ahmed
2026-05-06 1:57 ` [PATCH v6 14/16] KVM: selftests: Allocate a dedicated guest page for x86 L2 guest stack Yosry Ahmed
2026-05-06 1:57 ` [PATCH v6 15/16] KVM: selftests: Drop L1-provided stacks for L2 guests on x86 Yosry Ahmed
2026-05-06 1:57 ` [PATCH v6 16/16] KVM: selftests: Add svm_pmu_host_guest_test for Host-Only/Guest-Only bits Yosry Ahmed
2026-05-06 2:00 ` [PATCH v6 00/16] Yosry Ahmed
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