* FAILED: patch "[PATCH] perf/x86/intel: Don't clear perf metrics overflow bit" failed to apply to 5.15-stable tree
@ 2025-04-21 14:03 gregkh
0 siblings, 0 replies; 2+ messages in thread
From: gregkh @ 2025-04-21 14:03 UTC (permalink / raw)
To: dapeng1.mi, kan.liang, mingo, peterz; +Cc: stable
The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x a5f5e1238f4ff919816f69e77d2537a48911767b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025042159-unison-erupt-4734@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From a5f5e1238f4ff919816f69e77d2537a48911767b Mon Sep 17 00:00:00 2001
From: Dapeng Mi <dapeng1.mi@linux.intel.com>
Date: Tue, 15 Apr 2025 10:41:34 +0000
Subject: [PATCH] perf/x86/intel: Don't clear perf metrics overflow bit
unconditionally
The below code would always unconditionally clear other status bits like
perf metrics overflow bit once PEBS buffer overflows:
status &= intel_ctrl | GLOBAL_STATUS_TRACE_TOPAPMI;
This is incorrect. Perf metrics overflow bit should be cleared only when
fixed counter 3 in PEBS counter group. Otherwise perf metrics overflow
could be missed to handle.
Closes: https://lore.kernel.org/all/20250225110012.GK31462@noisy.programming.kicks-ass.net/
Fixes: 7b2c05a15d29 ("perf/x86/intel: Generic support for hardware TopDown metrics")
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20250415104135.318169-1-dapeng1.mi@linux.intel.com
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index 09d2d66c9f21..2b70a3adde2f 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -3049,7 +3049,6 @@ static int handle_pmi_common(struct pt_regs *regs, u64 status)
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
int bit;
int handled = 0;
- u64 intel_ctrl = hybrid(cpuc->pmu, intel_ctrl);
inc_irq_stat(apic_perf_irqs);
@@ -3093,7 +3092,6 @@ static int handle_pmi_common(struct pt_regs *regs, u64 status)
handled++;
x86_pmu_handle_guest_pebs(regs, &data);
static_call(x86_pmu_drain_pebs)(regs, &data);
- status &= intel_ctrl | GLOBAL_STATUS_TRACE_TOPAPMI;
/*
* PMI throttle may be triggered, which stops the PEBS event.
@@ -3104,6 +3102,15 @@ static int handle_pmi_common(struct pt_regs *regs, u64 status)
*/
if (pebs_enabled != cpuc->pebs_enabled)
wrmsrl(MSR_IA32_PEBS_ENABLE, cpuc->pebs_enabled);
+
+ /*
+ * Above PEBS handler (PEBS counters snapshotting) has updated fixed
+ * counter 3 and perf metrics counts if they are in counter group,
+ * unnecessary to update again.
+ */
+ if (cpuc->events[INTEL_PMC_IDX_FIXED_SLOTS] &&
+ is_pebs_counter_event_group(cpuc->events[INTEL_PMC_IDX_FIXED_SLOTS]))
+ status &= ~GLOBAL_STATUS_PERF_METRICS_OVF_BIT;
}
/*
@@ -3123,6 +3130,8 @@ static int handle_pmi_common(struct pt_regs *regs, u64 status)
static_call(intel_pmu_update_topdown_event)(NULL, NULL);
}
+ status &= hybrid(cpuc->pmu, intel_ctrl);
+
/*
* Checkpointed counters can lead to 'spurious' PMIs because the
* rollback caused by the PMI will have cleared the overflow status
^ permalink raw reply related [flat|nested] 2+ messages in thread
* FAILED: patch "[PATCH] perf/x86/intel: Don't clear perf metrics overflow bit" failed to apply to 5.15-stable tree
@ 2025-04-21 14:10 gregkh
0 siblings, 0 replies; 2+ messages in thread
From: gregkh @ 2025-04-21 14:10 UTC (permalink / raw)
To: dapeng1.mi, kan.liang, mingo, peterz; +Cc: stable
The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x a5f5e1238f4ff919816f69e77d2537a48911767b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025042127-dinner-elixir-4619@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From a5f5e1238f4ff919816f69e77d2537a48911767b Mon Sep 17 00:00:00 2001
From: Dapeng Mi <dapeng1.mi@linux.intel.com>
Date: Tue, 15 Apr 2025 10:41:34 +0000
Subject: [PATCH] perf/x86/intel: Don't clear perf metrics overflow bit
unconditionally
The below code would always unconditionally clear other status bits like
perf metrics overflow bit once PEBS buffer overflows:
status &= intel_ctrl | GLOBAL_STATUS_TRACE_TOPAPMI;
This is incorrect. Perf metrics overflow bit should be cleared only when
fixed counter 3 in PEBS counter group. Otherwise perf metrics overflow
could be missed to handle.
Closes: https://lore.kernel.org/all/20250225110012.GK31462@noisy.programming.kicks-ass.net/
Fixes: 7b2c05a15d29 ("perf/x86/intel: Generic support for hardware TopDown metrics")
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20250415104135.318169-1-dapeng1.mi@linux.intel.com
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index 09d2d66c9f21..2b70a3adde2f 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -3049,7 +3049,6 @@ static int handle_pmi_common(struct pt_regs *regs, u64 status)
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
int bit;
int handled = 0;
- u64 intel_ctrl = hybrid(cpuc->pmu, intel_ctrl);
inc_irq_stat(apic_perf_irqs);
@@ -3093,7 +3092,6 @@ static int handle_pmi_common(struct pt_regs *regs, u64 status)
handled++;
x86_pmu_handle_guest_pebs(regs, &data);
static_call(x86_pmu_drain_pebs)(regs, &data);
- status &= intel_ctrl | GLOBAL_STATUS_TRACE_TOPAPMI;
/*
* PMI throttle may be triggered, which stops the PEBS event.
@@ -3104,6 +3102,15 @@ static int handle_pmi_common(struct pt_regs *regs, u64 status)
*/
if (pebs_enabled != cpuc->pebs_enabled)
wrmsrl(MSR_IA32_PEBS_ENABLE, cpuc->pebs_enabled);
+
+ /*
+ * Above PEBS handler (PEBS counters snapshotting) has updated fixed
+ * counter 3 and perf metrics counts if they are in counter group,
+ * unnecessary to update again.
+ */
+ if (cpuc->events[INTEL_PMC_IDX_FIXED_SLOTS] &&
+ is_pebs_counter_event_group(cpuc->events[INTEL_PMC_IDX_FIXED_SLOTS]))
+ status &= ~GLOBAL_STATUS_PERF_METRICS_OVF_BIT;
}
/*
@@ -3123,6 +3130,8 @@ static int handle_pmi_common(struct pt_regs *regs, u64 status)
static_call(intel_pmu_update_topdown_event)(NULL, NULL);
}
+ status &= hybrid(cpuc->pmu, intel_ctrl);
+
/*
* Checkpointed counters can lead to 'spurious' PMIs because the
* rollback caused by the PMI will have cleared the overflow status
^ permalink raw reply related [flat|nested] 2+ messages in thread
end of thread, other threads:[~2025-04-21 14:10 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-04-21 14:10 FAILED: patch "[PATCH] perf/x86/intel: Don't clear perf metrics overflow bit" failed to apply to 5.15-stable tree gregkh
-- strict thread matches above, loose matches on Subject: below --
2025-04-21 14:03 gregkh
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox