From: Dapeng Mi <dapeng1.mi@linux.intel.com>
To: Sean Christopherson <seanjc@google.com>,
Paolo Bonzini <pbonzini@redhat.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
Jim Mattson <jmattson@google.com>,
Mingwei Zhang <mizhang@google.com>,
Zide Chen <zide.chen@intel.com>,
Das Sandipan <Sandipan.Das@amd.com>,
Shukla Manali <Manali.Shukla@amd.com>,
Xiaoyao Li <xiaoyao.li@intel.com>,
Dapeng Mi <dapeng1.mi@intel.com>,
dongsheng <dongsheng.x.zhang@intel.com>,
Dapeng Mi <dapeng1.mi@linux.intel.com>,
Yi Lai <yi1.lai@intel.com>
Subject: [kvm-unit-tests patch v3 2/8] x86/pmu: Relax precise count validation for Intel overcounted platforms
Date: Wed, 3 Sep 2025 14:45:55 +0800 [thread overview]
Message-ID: <20250903064601.32131-3-dapeng1.mi@linux.intel.com> (raw)
In-Reply-To: <20250903064601.32131-1-dapeng1.mi@linux.intel.com>
From: dongsheng <dongsheng.x.zhang@intel.com>
As the VM-Exit/VM-Entry overcount issue on Intel Atom platforms,
there is no way to validate the precise count for "instructions" and
"branches" events on these overcounted Atom platforms. Thus relax the
precise count validation on these overcounted platforms.
Signed-off-by: dongsheng <dongsheng.x.zhang@intel.com>
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Tested-by: Yi Lai <yi1.lai@intel.com>
---
x86/pmu.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/x86/pmu.c b/x86/pmu.c
index 87365aff..04946d10 100644
--- a/x86/pmu.c
+++ b/x86/pmu.c
@@ -237,10 +237,15 @@ static void adjust_events_range(struct pmu_event *gp_events,
* occur while running the measured code, e.g. if the host takes IRQs.
*/
if (pmu.is_intel && this_cpu_has_perf_global_ctrl()) {
- gp_events[instruction_idx].min = LOOP_INSNS;
- gp_events[instruction_idx].max = LOOP_INSNS;
- gp_events[branch_idx].min = LOOP_BRANCHES;
- gp_events[branch_idx].max = LOOP_BRANCHES;
+ if (!(intel_inst_overcount_flags & INST_RETIRED_OVERCOUNT)) {
+ gp_events[instruction_idx].min = LOOP_INSNS;
+ gp_events[instruction_idx].max = LOOP_INSNS;
+ }
+
+ if (!(intel_inst_overcount_flags & BR_RETIRED_OVERCOUNT)) {
+ gp_events[branch_idx].min = LOOP_BRANCHES;
+ gp_events[branch_idx].max = LOOP_BRANCHES;
+ }
}
/*
--
2.34.1
next prev parent reply other threads:[~2025-09-03 6:47 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-09-03 6:45 [kvm-unit-tests patch v3 0/8] Fix pmu test errors on GNR/SRF/CWF Dapeng Mi
2025-09-03 6:45 ` [kvm-unit-tests patch v3 1/8] x86/pmu: Add helper to detect Intel overcount issues Dapeng Mi
2025-11-20 22:27 ` Sean Christopherson
2025-11-21 1:18 ` Mi, Dapeng
2025-09-03 6:45 ` Dapeng Mi [this message]
2025-09-03 6:45 ` [kvm-unit-tests patch v3 3/8] x86/pmu: Fix incorrect masking of fixed counters Dapeng Mi
2025-11-20 22:28 ` Sean Christopherson
2025-11-21 1:25 ` Mi, Dapeng
2025-09-03 6:45 ` [kvm-unit-tests patch v3 4/8] x86/pmu: Handle instruction overcount issue in overflow test Dapeng Mi
2025-09-03 6:45 ` [kvm-unit-tests patch v3 5/8] x86/pmu: Relax precise count check for emulated instructions tests Dapeng Mi
2025-11-20 22:29 ` Sean Christopherson
2025-11-21 0:53 ` Mi, Dapeng
2025-09-03 6:45 ` [kvm-unit-tests patch v3 6/8] x86/pmu: Expand "llc references" upper limit for broader compatibility Dapeng Mi
2025-09-03 6:46 ` [kvm-unit-tests patch v3 7/8] x86: pmu_pebs: Remove abundant data_cfg_match calculation Dapeng Mi
2025-09-03 6:46 ` [kvm-unit-tests patch v3 8/8] x86: pmu_pebs: Support to validate timed PEBS record on GNR/SRF Dapeng Mi
2025-11-20 22:30 ` [kvm-unit-tests patch v3 0/8] Fix pmu test errors on GNR/SRF/CWF Sean Christopherson
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=20250903064601.32131-3-dapeng1.mi@linux.intel.com \
--to=dapeng1.mi@linux.intel.com \
--cc=Manali.Shukla@amd.com \
--cc=Sandipan.Das@amd.com \
--cc=dapeng1.mi@intel.com \
--cc=dongsheng.x.zhang@intel.com \
--cc=jmattson@google.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mizhang@google.com \
--cc=pbonzini@redhat.com \
--cc=seanjc@google.com \
--cc=xiaoyao.li@intel.com \
--cc=yi1.lai@intel.com \
--cc=zide.chen@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