[PATCH] drivers/perf: Change WARN_ON() to dev_err() on irq_set_affinity() failure

[Yicong Yang]

From: Yicong Yang <yangyicong@xxxxxxxxxxxxx>

The WARN_ON() on irq_set_affinity() failure is misused according to the [1]
and may crash people's box unintentionally. This may also be redundant since
in the failure case we may also trigger the WARN and dump the stack in the
perf core[2] for a second time.

So change the WARN_ON() to dev_err() to just print the failure message.

[1] https://github.com/torvalds/linux/blob/master/include/asm-generic/bug.h#L74
[2] https://github.com/torvalds/linux/blob/master/kernel/events/core.c#L313

Suggested-by: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>
[https://lore.kernel.org/lkml/YuOi3i0XHV++z1YI@xxxxxxxxx/]
Signed-off-by: Yicong Yang <yangyicong@xxxxxxxxxxxxx>
---
 drivers/perf/arm-ccn.c                   | 5 +++--
 drivers/perf/arm_dmc620_pmu.c            | 3 ++-
 drivers/perf/arm_smmuv3_pmu.c            | 6 ++++--
 drivers/perf/fsl_imx8_ddr_perf.c         | 3 ++-
 drivers/perf/hisilicon/hisi_pcie_pmu.c   | 6 ++++--
 drivers/perf/hisilicon/hisi_uncore_pmu.c | 6 ++++--
 drivers/perf/qcom_l2_pmu.c               | 8 ++++++--
 drivers/perf/xgene_pmu.c                 | 6 ++++--
 8 files changed, 29 insertions(+), 14 deletions(-)

diff --git a/drivers/perf/arm-ccn.c b/drivers/perf/arm-ccn.c
index 728d13d8e98a..83abd909ba49 100644
--- a/drivers/perf/arm-ccn.c
+++ b/drivers/perf/arm-ccn.c
@@ -1210,8 +1210,9 @@ static int arm_ccn_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
 		return 0;
 	perf_pmu_migrate_context(&dt->pmu, cpu, target);
 	dt->cpu = target;
-	if (ccn->irq)
-		WARN_ON(irq_set_affinity(ccn->irq, cpumask_of(dt->cpu)));
+	if (ccn->irq && irq_set_affinity(ccn->irq, cpumask_of(dt->cpu)))
+		dev_err(ccn->dev, "Failed to set interrupt affinity\n");
+
 	return 0;
 }
 
diff --git a/drivers/perf/arm_dmc620_pmu.c b/drivers/perf/arm_dmc620_pmu.c
index 280a6ae3e27c..b59d3d9eb779 100644
--- a/drivers/perf/arm_dmc620_pmu.c
+++ b/drivers/perf/arm_dmc620_pmu.c
@@ -621,7 +621,8 @@ static int dmc620_pmu_cpu_teardown(unsigned int cpu,
 		perf_pmu_migrate_context(&dmc620_pmu->pmu, irq->cpu, target);
 	mutex_unlock(&dmc620_pmu_irqs_lock);
 
-	WARN_ON(irq_set_affinity(irq->irq_num, cpumask_of(target)));
+	if (irq_set_affinity(irq->irq_num, cpumask_of(target)))
+		dev_err(dmc620_pmu->pmu.dev, "Failed to set interrupt affinity\n");
 	irq->cpu = target;
 
 	return 0;
diff --git a/drivers/perf/arm_smmuv3_pmu.c b/drivers/perf/arm_smmuv3_pmu.c
index 00d4c45a8017..05e1b3e274d7 100644
--- a/drivers/perf/arm_smmuv3_pmu.c
+++ b/drivers/perf/arm_smmuv3_pmu.c
@@ -646,7 +646,8 @@ static int smmu_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
 
 	perf_pmu_migrate_context(&smmu_pmu->pmu, cpu, target);
 	smmu_pmu->on_cpu = target;
-	WARN_ON(irq_set_affinity(smmu_pmu->irq, cpumask_of(target)));
+	if (irq_set_affinity(smmu_pmu->irq, cpumask_of(target)))
+		dev_err(smmu_pmu->dev, "Failed to set interrupt affinity\n");
 
 	return 0;
 }
@@ -892,7 +893,8 @@ static int smmu_pmu_probe(struct platform_device *pdev)
 
 	/* Pick one CPU to be the preferred one to use */
 	smmu_pmu->on_cpu = raw_smp_processor_id();
-	WARN_ON(irq_set_affinity(smmu_pmu->irq, cpumask_of(smmu_pmu->on_cpu)));
+	if (irq_set_affinity(smmu_pmu->irq, cpumask_of(smmu_pmu->on_cpu)))
+		dev_err(dev, "Failed to set interrupt affinity\n");
 
 	err = cpuhp_state_add_instance_nocalls(cpuhp_state_num,
 					       &smmu_pmu->node);
diff --git a/drivers/perf/fsl_imx8_ddr_perf.c b/drivers/perf/fsl_imx8_ddr_perf.c
index 8e058e08fe81..c44192e2d9db 100644
--- a/drivers/perf/fsl_imx8_ddr_perf.c
+++ b/drivers/perf/fsl_imx8_ddr_perf.c
@@ -671,7 +671,8 @@ static int ddr_perf_offline_cpu(unsigned int cpu, struct hlist_node *node)
 	perf_pmu_migrate_context(&pmu->pmu, cpu, target);
 	pmu->cpu = target;
 
-	WARN_ON(irq_set_affinity(pmu->irq, cpumask_of(pmu->cpu)));
+	if (irq_set_affinity(pmu->irq, cpumask_of(pmu->cpu)))
+		dev_err(pmu->dev, "Failed to set interrupt affinity\n");
 
 	return 0;
 }
diff --git a/drivers/perf/hisilicon/hisi_pcie_pmu.c b/drivers/perf/hisilicon/hisi_pcie_pmu.c
index 21771708597d..90aed9e51396 100644
--- a/drivers/perf/hisilicon/hisi_pcie_pmu.c
+++ b/drivers/perf/hisilicon/hisi_pcie_pmu.c
@@ -655,7 +655,8 @@ static int hisi_pcie_pmu_online_cpu(unsigned int cpu, struct hlist_node *node)
 
 	if (pcie_pmu->on_cpu == -1) {
 		pcie_pmu->on_cpu = cpu;
-		WARN_ON(irq_set_affinity(pcie_pmu->irq, cpumask_of(cpu)));
+		if (irq_set_affinity(pcie_pmu->irq, cpumask_of(cpu)))
+			pci_err(pcie_pmu->pdev, "Failed to set interrupt affinity\n");
 	}
 
 	return 0;
@@ -681,7 +682,8 @@ static int hisi_pcie_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
 	perf_pmu_migrate_context(&pcie_pmu->pmu, cpu, target);
 	/* Use this CPU for event counting */
 	pcie_pmu->on_cpu = target;
-	WARN_ON(irq_set_affinity(pcie_pmu->irq, cpumask_of(target)));
+	if (irq_set_affinity(pcie_pmu->irq, cpumask_of(target)))
+		pci_err(pcie_pmu->pdev, "Failed to set interrupt affinity\n");
 
 	return 0;
 }
diff --git a/drivers/perf/hisilicon/hisi_uncore_pmu.c b/drivers/perf/hisilicon/hisi_uncore_pmu.c
index fbc8a93d5eac..74397b5ec889 100644
--- a/drivers/perf/hisilicon/hisi_uncore_pmu.c
+++ b/drivers/perf/hisilicon/hisi_uncore_pmu.c
@@ -492,7 +492,8 @@ int hisi_uncore_pmu_online_cpu(unsigned int cpu, struct hlist_node *node)
 	hisi_pmu->on_cpu = cpu;
 
 	/* Overflow interrupt also should use the same CPU */
-	WARN_ON(irq_set_affinity(hisi_pmu->irq, cpumask_of(cpu)));
+	if (irq_set_affinity(hisi_pmu->irq, cpumask_of(cpu)))
+		dev_err(hisi_pmu->dev, "Failed to set interrupt affinity\n");
 
 	return 0;
 }
@@ -525,7 +526,8 @@ int hisi_uncore_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
 	perf_pmu_migrate_context(&hisi_pmu->pmu, cpu, target);
 	/* Use this CPU for event counting */
 	hisi_pmu->on_cpu = target;
-	WARN_ON(irq_set_affinity(hisi_pmu->irq, cpumask_of(target)));
+	if (irq_set_affinity(hisi_pmu->irq, cpumask_of(target)))
+		dev_err(hisi_pmu->dev, "Failed to set interrupt affinity\n");
 
 	return 0;
 }
diff --git a/drivers/perf/qcom_l2_pmu.c b/drivers/perf/qcom_l2_pmu.c
index 30234c261b05..c6fe01c7e637 100644
--- a/drivers/perf/qcom_l2_pmu.c
+++ b/drivers/perf/qcom_l2_pmu.c
@@ -793,7 +793,9 @@ static int l2cache_pmu_online_cpu(unsigned int cpu, struct hlist_node *node)
 	cpumask_set_cpu(cpu, &l2cache_pmu->cpumask);
 	cluster_pmu_reset();
 
-	WARN_ON(irq_set_affinity(cluster->irq, cpumask_of(cpu)));
+	if (irq_set_affinity(cluster->irq, cpumask_of(cpu)))
+		dev_err(&l2cache_pmu->pdev->dev,
+			"Failed to set interrupt affinity\n");
 	enable_irq(cluster->irq);
 
 	return 0;
@@ -831,7 +833,9 @@ static int l2cache_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
 	perf_pmu_migrate_context(&l2cache_pmu->pmu, cpu, target);
 	cluster->on_cpu = target;
 	cpumask_set_cpu(target, &l2cache_pmu->cpumask);
-	WARN_ON(irq_set_affinity(cluster->irq, cpumask_of(target)));
+	if (irq_set_affinity(cluster->irq, cpumask_of(target)))
+		dev_err(&l2cache_pmu->pdev->dev,
+			"Failed to set interrupt affinity\n");
 
 	return 0;
 }
diff --git a/drivers/perf/xgene_pmu.c b/drivers/perf/xgene_pmu.c
index 0c32dffc7ede..f31e678fdb69 100644
--- a/drivers/perf/xgene_pmu.c
+++ b/drivers/perf/xgene_pmu.c
@@ -1790,7 +1790,8 @@ static int xgene_pmu_online_cpu(unsigned int cpu, struct hlist_node *node)
 		cpumask_set_cpu(cpu, &xgene_pmu->cpu);
 
 	/* Overflow interrupt also should use the same CPU */
-	WARN_ON(irq_set_affinity(xgene_pmu->irq, &xgene_pmu->cpu));
+	if (irq_set_affinity(xgene_pmu->irq, &xgene_pmu->cpu))
+		dev_err(xgene_pmu->dev, "Failed to set interrupt affinity\n");
 
 	return 0;
 }
@@ -1823,7 +1824,8 @@ static int xgene_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
 
 	cpumask_set_cpu(target, &xgene_pmu->cpu);
 	/* Overflow interrupt also should use the same CPU */
-	WARN_ON(irq_set_affinity(xgene_pmu->irq, &xgene_pmu->cpu));
+	if (irq_set_affinity(xgene_pmu->irq, &xgene_pmu->cpu))
+		dev_err(xgene_pmu->dev, "Failed to set interrupt affinity\n");
 
 	return 0;
 }
-- 
2.24.0