[PATCH] perf/x86/intel: Limit the period on Haswell

[PATCH] perf/x86/intel: Limit the period on Haswell

[kan.liang]

From: Kan Liang <kan.liang@linux.intel.com>

Running the ltp test cve-2015-3290 concurrently reports the following
warnings.

perfevents: irq loop stuck!
  WARNING: CPU: 31 PID: 32438 at arch/x86/events/intel/core.c:3174
  intel_pmu_handle_irq+0x285/0x370
  Call Trace:
   <NMI>
   ? __warn+0xa4/0x220
   ? intel_pmu_handle_irq+0x285/0x370
   ? __report_bug+0x123/0x130
   ? intel_pmu_handle_irq+0x285/0x370
   ? __report_bug+0x123/0x130
   ? intel_pmu_handle_irq+0x285/0x370
   ? report_bug+0x3e/0xa0
   ? handle_bug+0x3c/0x70
   ? exc_invalid_op+0x18/0x50
   ? asm_exc_invalid_op+0x1a/0x20
   ? irq_work_claim+0x1e/0x40
   ? intel_pmu_handle_irq+0x285/0x370
   perf_event_nmi_handler+0x3d/0x60
   nmi_handle+0x104/0x330

Thanks to Thomas Gleixner's analysis, the issue is caused by the low
initial period (1) of the frequency estimation algorithm, which triggers
the defects of the HW, specifically erratum HSW11 and HSW143. (For the
details, please refer https://lore.kernel.org/lkml/87plq9l5d2.ffs@tglx/)

The HSW11 requires a period larger than 100 for the INST_RETIRED.ALL
event, but the initial period in the freq mode is 1. The erratum is the
same as the BDM11, which has been supported in the kernel. A minimum
period of 128 is enforced as well on HSW.

HSW143 is regarding that the fixed counter 1 may overcount 32 with the
Hyper-Threading is enabled. However, based on the test, the hardware
has more issues than it tells. Besides the fixed counter 1, the message
'interrupt took too long' can be observed on any counter which was armed
with a period < 32 and two events expired in the same NMI. A minimum
period of 32 is enforced for the rest of the events.
The recommended workaround code of the HSW143 is not implemented.
Because it only addresses the issue for the fixed counter. It brings
extra overhead through extra MSR writing. No related overcounting issue
has been reported so far.

Fixes: 3a632cb229bf ("perf/x86/intel: Add simple Haswell PMU support")
Reported-by: Li Huafei <lihuafei1@huawei.com>
Closes: https://lore.kernel.org/lkml/20240729223328.327835-1-lihuafei1@huawei.com/
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: stable@vger.kernel.org
---
 arch/x86/events/intel/core.c | 23 +++++++++++++++++++++--
 1 file changed, 21 insertions(+), 2 deletions(-)

diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index e8bd45556c30..605ed19043ed 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -4634,6 +4634,25 @@ static enum hybrid_cpu_type adl_get_hybrid_cpu_type(void)
 	return HYBRID_INTEL_CORE;
 }
 
+static inline bool erratum_hsw11(struct perf_event *event)
+{
+	return (event->hw.config & INTEL_ARCH_EVENT_MASK) ==
+		X86_CONFIG(.event=0xc0, .umask=0x01);
+}
+
+/*
+ * The HSW11 requires a period larger than 100 which is the same as the BDM11.
+ * A minimum period of 128 is enforced as well for the INST_RETIRED.ALL.
+ *
+ * The message 'interrupt took too long' can be observed on any counter which
+ * was armed with a period < 32 and two events expired in the same NMI.
+ * A minimum period of 32 is enforced for the rest of the events.
+ */
+static void hsw_limit_period(struct perf_event *event, s64 *left)
+{
+	*left = max(*left, erratum_hsw11(event) ? 128 : 32);
+}
+
 /*
  * Broadwell:
  *
@@ -4651,8 +4670,7 @@ static enum hybrid_cpu_type adl_get_hybrid_cpu_type(void)
  */
 static void bdw_limit_period(struct perf_event *event, s64 *left)
 {
-	if ((event->hw.config & INTEL_ARCH_EVENT_MASK) ==
-			X86_CONFIG(.event=0xc0, .umask=0x01)) {
+	if (erratum_hsw11(event)) {
 		if (*left < 128)
 			*left = 128;
 		*left &= ~0x3fULL;
@@ -6821,6 +6839,7 @@ __init int intel_pmu_init(void)
 
 		x86_pmu.hw_config = hsw_hw_config;
 		x86_pmu.get_event_constraints = hsw_get_event_constraints;
+		x86_pmu.limit_period = hsw_limit_period;
 		x86_pmu.lbr_double_abort = true;
 		extra_attr = boot_cpu_has(X86_FEATURE_RTM) ?
 			hsw_format_attr : nhm_format_attr;
-- 
2.38.1

[tip: perf/urgent] perf/x86/intel: Limit the period on Haswell

[tip-bot2 for Kan Liang]

The following commit has been merged into the perf/urgent branch of tip:

Commit-ID:     25dfc9e357af8aed1ca79b318a73f2c59c1f0b2b
Gitweb:        https://git.kernel.org/tip/25dfc9e357af8aed1ca79b318a73f2c59c1f0b2b
Author:        Kan Liang <kan.liang@linux.intel.com>
AuthorDate:    Mon, 19 Aug 2024 11:30:04 -07:00
Committer:     Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Sun, 25 Aug 2024 16:49:05 +02:00

perf/x86/intel: Limit the period on Haswell

Running the ltp test cve-2015-3290 concurrently reports the following
warnings.

perfevents: irq loop stuck!
  WARNING: CPU: 31 PID: 32438 at arch/x86/events/intel/core.c:3174
  intel_pmu_handle_irq+0x285/0x370
  Call Trace:
   <NMI>
   ? __warn+0xa4/0x220
   ? intel_pmu_handle_irq+0x285/0x370
   ? __report_bug+0x123/0x130
   ? intel_pmu_handle_irq+0x285/0x370
   ? __report_bug+0x123/0x130
   ? intel_pmu_handle_irq+0x285/0x370
   ? report_bug+0x3e/0xa0
   ? handle_bug+0x3c/0x70
   ? exc_invalid_op+0x18/0x50
   ? asm_exc_invalid_op+0x1a/0x20
   ? irq_work_claim+0x1e/0x40
   ? intel_pmu_handle_irq+0x285/0x370
   perf_event_nmi_handler+0x3d/0x60
   nmi_handle+0x104/0x330

Thanks to Thomas Gleixner's analysis, the issue is caused by the low
initial period (1) of the frequency estimation algorithm, which triggers
the defects of the HW, specifically erratum HSW11 and HSW143. (For the
details, please refer https://lore.kernel.org/lkml/87plq9l5d2.ffs@tglx/)

The HSW11 requires a period larger than 100 for the INST_RETIRED.ALL
event, but the initial period in the freq mode is 1. The erratum is the
same as the BDM11, which has been supported in the kernel. A minimum
period of 128 is enforced as well on HSW.

HSW143 is regarding that the fixed counter 1 may overcount 32 with the
Hyper-Threading is enabled. However, based on the test, the hardware
has more issues than it tells. Besides the fixed counter 1, the message
'interrupt took too long' can be observed on any counter which was armed
with a period < 32 and two events expired in the same NMI. A minimum
period of 32 is enforced for the rest of the events.
The recommended workaround code of the HSW143 is not implemented.
Because it only addresses the issue for the fixed counter. It brings
extra overhead through extra MSR writing. No related overcounting issue
has been reported so far.

Fixes: 3a632cb229bf ("perf/x86/intel: Add simple Haswell PMU support")
Reported-by: Li Huafei <lihuafei1@huawei.com>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240819183004.3132920-1-kan.liang@linux.intel.com
Closes: https://lore.kernel.org/lkml/20240729223328.327835-1-lihuafei1@huawei.com/
---
 arch/x86/events/intel/core.c | 23 +++++++++++++++++++++--
 1 file changed, 21 insertions(+), 2 deletions(-)

diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index 0c9c270..9e519d8 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -4589,6 +4589,25 @@ static enum hybrid_cpu_type adl_get_hybrid_cpu_type(void)
 	return HYBRID_INTEL_CORE;
 }
 
+static inline bool erratum_hsw11(struct perf_event *event)
+{
+	return (event->hw.config & INTEL_ARCH_EVENT_MASK) ==
+		X86_CONFIG(.event=0xc0, .umask=0x01);
+}
+
+/*
+ * The HSW11 requires a period larger than 100 which is the same as the BDM11.
+ * A minimum period of 128 is enforced as well for the INST_RETIRED.ALL.
+ *
+ * The message 'interrupt took too long' can be observed on any counter which
+ * was armed with a period < 32 and two events expired in the same NMI.
+ * A minimum period of 32 is enforced for the rest of the events.
+ */
+static void hsw_limit_period(struct perf_event *event, s64 *left)
+{
+	*left = max(*left, erratum_hsw11(event) ? 128 : 32);
+}
+
 /*
  * Broadwell:
  *
@@ -4606,8 +4625,7 @@ static enum hybrid_cpu_type adl_get_hybrid_cpu_type(void)
  */
 static void bdw_limit_period(struct perf_event *event, s64 *left)
 {
-	if ((event->hw.config & INTEL_ARCH_EVENT_MASK) ==
-			X86_CONFIG(.event=0xc0, .umask=0x01)) {
+	if (erratum_hsw11(event)) {
 		if (*left < 128)
 			*left = 128;
 		*left &= ~0x3fULL;
@@ -6766,6 +6784,7 @@ __init int intel_pmu_init(void)
 
 		x86_pmu.hw_config = hsw_hw_config;
 		x86_pmu.get_event_constraints = hsw_get_event_constraints;
+		x86_pmu.limit_period = hsw_limit_period;
 		x86_pmu.lbr_double_abort = true;
 		extra_attr = boot_cpu_has(X86_FEATURE_RTM) ?
 			hsw_format_attr : nhm_format_attr;