[PATCH v4 00/26] genirq: Add support for percpu_devid IRQ affinity

[PATCH v4 00/26] genirq: Add support for percpu_devid IRQ affinity

[Marc Zyngier]

This is the fourth version of this series, originally posted at [1],
which aims at allowing percpu_devid interrupt requests on the basis of
an affinity mask. See the original submission for the details of why
this is a desirable outcome.

From v3, we have some additional tidying up, thanks to Jonathan's
review, and a bunch of tags -- see changelog for details.

FWIW, I've pushed a branch at [0].

* From v3 [3]:

  - Additional cleanups in of_irq_get_affinity() (Jonathan)

  - Rebased on 6.18-rc2

  - Collected Abs, Rbs and Tbs, with thanks (Raphael, Jonathan,
    Jinjie, Suzuki, Sven, Will)

* From v2 [2]:

  - Turned of_node_to_fwnode() usage to of_fwnode_handle() (Jonathan)

  - Added a patch to finally kill of_node_to_fwnode()

  - Tidied-up documentation, comments and formatting (Jonathan)

  - Collected ABs and Rbs, with thanks (Jonathan, Suzuki, Sven)

* From v1 [1]:

  - Fixed NMI handling by getting rid of the NMI-specific flow
    handler, which was pretty useless anyway (Will)

  - As a result, killed a metric buttload worth of GICv3 code

  - Moved irq_fwspec out of irq_fwspec_info, and passed it as a
    parameter to irq_get_fwspec_info(), renamed from irq_get_info(),
    and applied some generous sanitisation of the structure (Thomas)

  - Dropped the rather useless fwspec validity flag (Thomas)

  - Rejigged the PMU per-CPU handling to better deal with the DT/ACPI
    differences, and drop some now useless patches (Will)

  - Plenty of cosmetic rework (Raphael, Thomas)

[0] git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git irq/ppi-affinity
[1] https://lore.kernel.org/r/20250908163127.2462948-1-maz@kernel.org
[2] https://lore.kernel.org/r/20250915085702.519996-1-maz@kernel.org
[3] https://lore.kernel.org/r/20250922082833.2038905-1-maz@kernel.org

Marc Zyngier (25):
  irqdomain: Add firmware info reporting interface
  ACPI: irq: Add IRQ affinity reporting interface
  of/irq: Add IRQ affinity reporting interface
  platform: Add firmware-agnostic irq and affinity retrieval interface
  irqchip/gic-v3: Add FW info retrieval support
  irqchip/apple-aic: Add FW info retrieval support
  coresight: trbe: Convert to new IRQ affinity retrieval API
  perf: arm_pmu: Convert to new IRQ affinity retrieval API
  perf: arm_spe_pmu: Convert to new IRQ affinity retrieval API
  irqchip/gic-v3: Switch high priority PPIs over to
    handle_percpu_devid_irq()
  genirq: Kill handle_percpu_devid_fasteoi_nmi()
  genirq: Merge irqaction::{dev_id,percpu_dev_id}
  genirq: Factor-in percpu irqaction creation
  genirq: Add affinity to percpu_devid interrupt requests
  genirq: Update request_percpu_nmi() to take an affinity
  genirq: Allow per-cpu interrupt sharing for non-overlapping affinities
  genirq: Add request_percpu_irq_affinity() helper
  perf: arm_spe_pmu: Request specific affinities for percpu IRQ
  coresight: trbe: Request specific affinities for percpu IRQ
  irqchip/gic-v3: Drop support for custom PPI partitions
  irqchip/apple-aic: Drop support for custom PMU irq partitions
  irqchip: Kill irq-partition-percpu
  genirq: Kill irq_{g,s}et_percpu_devid_partition()
  irqdomain: Kill of_node_to_fwnode() helper
  perf: arm_pmu: Kill last use of per-CPU cpu_armpmu pointer

Will Deacon (1):
  perf: arm_pmu: Request specific affinities for percpu NMI/IRQ

 arch/arm64/kernel/smp.c                      |   2 +-
 drivers/acpi/irq.c                           |  19 ++
 drivers/base/platform.c                      |  60 ++++-
 drivers/hwtracing/coresight/coresight-trbe.c |   9 +-
 drivers/irqchip/Kconfig                      |   4 -
 drivers/irqchip/Makefile                     |   1 -
 drivers/irqchip/irq-apple-aic.c              |  56 +++--
 drivers/irqchip/irq-gic-v3.c                 | 224 +++++------------
 drivers/irqchip/irq-partition-percpu.c       | 241 -------------------
 drivers/of/irq.c                             |  20 ++
 drivers/perf/arm_pmu.c                       |  49 ++--
 drivers/perf/arm_pmu_acpi.c                  |   2 +-
 drivers/perf/arm_pmu_platform.c              |  20 +-
 drivers/perf/arm_pmuv3.c                     |   2 +-
 drivers/perf/arm_spe_pmu.c                   |  13 +-
 include/linux/acpi.h                         |   7 +
 include/linux/interrupt.h                    |  24 +-
 include/linux/irq.h                          |   5 -
 include/linux/irqchip/irq-partition-percpu.h |  53 ----
 include/linux/irqdesc.h                      |   1 -
 include/linux/irqdomain.h                    |  33 ++-
 include/linux/of_irq.h                       |   7 +
 include/linux/perf/arm_pmu.h                 |   6 +-
 include/linux/platform_device.h              |   2 +
 kernel/irq/chip.c                            |  33 +--
 kernel/irq/irqdesc.c                         |  24 +-
 kernel/irq/irqdomain.c                       |  32 ++-
 kernel/irq/manage.c                          | 125 +++++++---
 28 files changed, 419 insertions(+), 655 deletions(-)
 delete mode 100644 drivers/irqchip/irq-partition-percpu.c
 delete mode 100644 include/linux/irqchip/irq-partition-percpu.h

-- 
2.47.3

[PATCH v4 01/26] irqdomain: Add firmware info reporting interface

[Marc Zyngier]

Allow an irqdomain callback to report firmware-provided information
that is otherwise not available in a generic way. This is reported
using a new data structure (struct irq_fwspec_info).

This callback is optional and the only information that can be
reported currently is the affinity of an interrupt. However, the
containing structure is designed to be extensible, allowing other
potentially relevant information to be reported in the future.

Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 include/linux/irqdomain.h | 27 +++++++++++++++++++++++++++
 kernel/irq/irqdomain.c    | 32 +++++++++++++++++++++++++++-----
 2 files changed, 54 insertions(+), 5 deletions(-)

diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
index 4a86e6b915dd6..9d6a5e99394fa 100644
--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -44,6 +44,23 @@ struct irq_fwspec {
 	u32			param[IRQ_DOMAIN_IRQ_SPEC_PARAMS];
 };
 
+/**
+ * struct irq_fwspec_info - firmware provided IRQ information structure
+ *
+ * @flags:		Information validity flags
+ * @cpumask:		Affinity mask for this interrupt
+ *
+ * This structure reports firmware-specific information about an
+ * interrupt. The only significant information is the affinity of a
+ * per-CPU interrupt, but this is designed to be extended as required.
+ */
+struct irq_fwspec_info {
+	unsigned long		flags;
+	const struct cpumask	*affinity;
+};
+
+#define IRQ_FWSPEC_INFO_AFFINITY_VALID	BIT(0)
+
 /* Conversion function from of_phandle_args fields to fwspec  */
 void of_phandle_args_to_fwspec(struct device_node *np, const u32 *args,
 			       unsigned int count, struct irq_fwspec *fwspec);
@@ -69,6 +86,9 @@ void of_phandle_args_to_fwspec(struct device_node *np, const u32 *args,
  * @translate:	Given @fwspec, decode the hardware irq number (@out_hwirq) and
  *		linux irq type value (@out_type). This is a generalised @xlate
  *		(over struct irq_fwspec) and is preferred if provided.
+ * @get_fwspec_info:
+ *		Given @fwspec, report additional firmware-provided information in
+ *		@info. Optional.
  * @debug_show:	For domains to show specific data for an interrupt in debugfs.
  *
  * Functions below are provided by the driver and called whenever a new mapping
@@ -96,6 +116,7 @@ struct irq_domain_ops {
 	void	(*deactivate)(struct irq_domain *d, struct irq_data *irq_data);
 	int	(*translate)(struct irq_domain *d, struct irq_fwspec *fwspec,
 			     unsigned long *out_hwirq, unsigned int *out_type);
+	int	(*get_fwspec_info)(struct irq_fwspec *fwspec, struct irq_fwspec_info *info);
 #endif
 #ifdef CONFIG_GENERIC_IRQ_DEBUGFS
 	void	(*debug_show)(struct seq_file *m, struct irq_domain *d,
@@ -602,6 +623,8 @@ void irq_domain_free_irqs_parent(struct irq_domain *domain, unsigned int irq_bas
 
 int irq_domain_disconnect_hierarchy(struct irq_domain *domain, unsigned int virq);
 
+int irq_populate_fwspec_info(struct irq_fwspec *fwspec, struct irq_fwspec_info *info);
+
 static inline bool irq_domain_is_hierarchy(struct irq_domain *domain)
 {
 	return domain->flags & IRQ_DOMAIN_FLAG_HIERARCHY;
@@ -685,6 +708,10 @@ static inline bool irq_domain_is_msi_device(struct irq_domain *domain)
 	return false;
 }
 
+static inline int irq_populate_fwspec_info(struct irq_fwspec *fwspec, struct irq_fwspec_info *info)
+{
+	return -EINVAL;
+}
 #endif	/* CONFIG_IRQ_DOMAIN_HIERARCHY */
 
 #ifdef CONFIG_GENERIC_MSI_IRQ
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index dc473faadcc81..2652c4cfd877f 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -867,13 +867,9 @@ void of_phandle_args_to_fwspec(struct device_node *np, const u32 *args,
 }
 EXPORT_SYMBOL_GPL(of_phandle_args_to_fwspec);
 
-unsigned int irq_create_fwspec_mapping(struct irq_fwspec *fwspec)
+static struct irq_domain *fwspec_to_domain(struct irq_fwspec *fwspec)
 {
 	struct irq_domain *domain;
-	struct irq_data *irq_data;
-	irq_hw_number_t hwirq;
-	unsigned int type = IRQ_TYPE_NONE;
-	int virq;
 
 	if (fwspec->fwnode) {
 		domain = irq_find_matching_fwspec(fwspec, DOMAIN_BUS_WIRED);
@@ -883,6 +879,32 @@ unsigned int irq_create_fwspec_mapping(struct irq_fwspec *fwspec)
 		domain = irq_default_domain;
 	}
 
+	return domain;
+}
+
+#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
+int irq_populate_fwspec_info(struct irq_fwspec *fwspec, struct irq_fwspec_info *info)
+{
+	struct irq_domain *domain = fwspec_to_domain(fwspec);
+
+	memset(info, 0, sizeof(*info));
+
+	if (!domain || !domain->ops->get_fwspec_info)
+		return 0;
+
+	return domain->ops->get_fwspec_info(fwspec, info);
+}
+#endif
+
+unsigned int irq_create_fwspec_mapping(struct irq_fwspec *fwspec)
+{
+	unsigned int type = IRQ_TYPE_NONE;
+	struct irq_domain *domain;
+	struct irq_data *irq_data;
+	irq_hw_number_t hwirq;
+	int virq;
+
+	domain = fwspec_to_domain(fwspec);
 	if (!domain) {
 		pr_warn("no irq domain found for %s !\n",
 			of_node_full_name(to_of_node(fwspec->fwnode)));
-- 
2.47.3

[PATCH v4 02/26] ACPI: irq: Add IRQ affinity reporting interface

[Marc Zyngier]

Plug the irq_populate_fwspec_info() helper into the ACPI layer
to offer an IRQ affinity reporting function. This is currently
only supported for the CONFIG_ACPI_GENERIC_GSI configurations,
but could later be extended to legacy architectures if necessary.

Acked-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/acpi/irq.c   | 19 +++++++++++++++++++
 include/linux/acpi.h |  7 +++++++
 2 files changed, 26 insertions(+)

diff --git a/drivers/acpi/irq.c b/drivers/acpi/irq.c
index 76a856c32c4d0..d1595156c86a4 100644
--- a/drivers/acpi/irq.c
+++ b/drivers/acpi/irq.c
@@ -300,6 +300,25 @@ int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res)
 }
 EXPORT_SYMBOL_GPL(acpi_irq_get);
 
+const struct cpumask *acpi_irq_get_affinity(acpi_handle handle,
+					    unsigned int index)
+{
+	struct irq_fwspec_info info;
+	struct irq_fwspec fwspec;
+	unsigned long flags;
+
+	if (acpi_irq_parse_one(handle, index, &fwspec, &flags))
+		return NULL;
+
+	if (irq_populate_fwspec_info(&fwspec, &info))
+		return NULL;
+
+	if (!(info.flags & IRQ_FWSPEC_INFO_AFFINITY_VALID))
+		return NULL;
+
+	return info.affinity;
+}
+
 /**
  * acpi_set_irq_model - Setup the GSI irqdomain information
  * @model: the value assigned to acpi_irq_model
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 5ff5d99f6ead5..607db773b6721 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -1509,12 +1509,19 @@ static inline int acpi_parse_spcr(bool enable_earlycon, bool enable_console)
 
 #if IS_ENABLED(CONFIG_ACPI_GENERIC_GSI)
 int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res);
+const struct cpumask *acpi_irq_get_affinity(acpi_handle handle,
+					    unsigned int index);
 #else
 static inline
 int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res)
 {
 	return -EINVAL;
 }
+static inline const struct cpumask *acpi_irq_get_affinity(acpi_handle handle,
+							  unsigned int index)
+{
+	return NULL;
+}
 #endif
 
 #ifdef CONFIG_ACPI_LPIT
-- 
2.47.3

[PATCH v4 03/26] of/irq: Add IRQ affinity reporting interface

[Marc Zyngier]

Plug the irq_populate_fwspec_info() helper into the OF layer
to offer an IRQ affinity reporting function.

Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/of/irq.c       | 20 ++++++++++++++++++++
 include/linux/of_irq.h |  7 +++++++
 2 files changed, 27 insertions(+)

diff --git a/drivers/of/irq.c b/drivers/of/irq.c
index 65c3c23255b74..168fde921bd27 100644
--- a/drivers/of/irq.c
+++ b/drivers/of/irq.c
@@ -479,6 +479,26 @@ int of_irq_get(struct device_node *dev, int index)
 }
 EXPORT_SYMBOL_GPL(of_irq_get);
 
+const struct cpumask *of_irq_get_affinity(struct device_node *dev, int index)
+{
+	struct of_phandle_args oirq;
+	struct irq_fwspec_info info;
+	struct irq_fwspec fwspec;
+	int rc;
+
+	rc = of_irq_parse_one(dev, index, &oirq);
+	if (rc)
+		return NULL;
+
+	of_phandle_args_to_fwspec(oirq.np, oirq.args, oirq.args_count,
+				  &fwspec);
+
+	if (irq_populate_fwspec_info(&fwspec, &info))
+		return NULL;
+
+	return info.affinity;
+}
+
 /**
  * of_irq_get_byname - Decode a node's IRQ and return it as a Linux IRQ number
  * @dev: pointer to device tree node
diff --git a/include/linux/of_irq.h b/include/linux/of_irq.h
index 1db8543dfc8a6..1c2bc02818071 100644
--- a/include/linux/of_irq.h
+++ b/include/linux/of_irq.h
@@ -43,6 +43,8 @@ extern int of_irq_parse_one(struct device_node *device, int index,
 			  struct of_phandle_args *out_irq);
 extern int of_irq_count(struct device_node *dev);
 extern int of_irq_get(struct device_node *dev, int index);
+extern const struct cpumask *of_irq_get_affinity(struct device_node *dev,
+						      int index);
 extern int of_irq_get_byname(struct device_node *dev, const char *name);
 extern int of_irq_to_resource_table(struct device_node *dev,
 		struct resource *res, int nr_irqs);
@@ -76,6 +78,11 @@ static inline int of_irq_get_byname(struct device_node *dev, const char *name)
 {
 	return 0;
 }
+static inline const struct cpumask *of_irq_get_affinity(struct device_node *dev,
+							int index)
+{
+	return NULL;
+}
 static inline int of_irq_to_resource_table(struct device_node *dev,
 					   struct resource *res, int nr_irqs)
 {
-- 
2.47.3

[PATCH v4 04/26] platform: Add firmware-agnostic irq and affinity retrieval interface

[Marc Zyngier]

Expand platform_get_irq_optional() to also return an affinity if
available, renaming it to platform_get_irq_affinity() in the
process.

platform_get_irq_optional() is preserved with its current semantics
by calling into the new helper with a NULL affinity pointer.

Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/base/platform.c         | 60 +++++++++++++++++++++++++++------
 include/linux/platform_device.h |  2 ++
 2 files changed, 52 insertions(+), 10 deletions(-)

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index 09450349cf323..3a058f63ef0d3 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -150,25 +150,37 @@ devm_platform_ioremap_resource_byname(struct platform_device *pdev,
 EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource_byname);
 #endif /* CONFIG_HAS_IOMEM */
 
+static const struct cpumask *get_irq_affinity(struct platform_device *dev,
+					      unsigned int num)
+{
+	const struct cpumask *mask = NULL;
+#ifndef CONFIG_SPARC
+	struct fwnode_handle *fwnode = dev_fwnode(&dev->dev);
+
+	if (is_of_node(fwnode))
+		mask = of_irq_get_affinity(to_of_node(fwnode), num);
+	else if (is_acpi_device_node(fwnode))
+		mask = acpi_irq_get_affinity(ACPI_HANDLE_FWNODE(fwnode), num);
+#endif
+
+	return mask ?: cpu_possible_mask;
+}
+
 /**
- * platform_get_irq_optional - get an optional IRQ for a device
+ * platform_get_irq_affinity - get an optional IRQ and its affinity for a device
  * @dev: platform device
  * @num: IRQ number index
+ * @affinity: optional cpumask pointer to get the affinity of a per-cpu IRQ
  *
  * Gets an IRQ for a platform device. Device drivers should check the return
  * value for errors so as to not pass a negative integer value to the
- * request_irq() APIs. This is the same as platform_get_irq(), except that it
- * does not print an error message if an IRQ can not be obtained.
- *
- * For example::
- *
- *		int irq = platform_get_irq_optional(pdev, 0);
- *		if (irq < 0)
- *			return irq;
+ * request_irq() APIs. Optional affinity information is provided in the
+ * affinity pointer if available, and NULL otherwise.
  *
  * Return: non-zero IRQ number on success, negative error number on failure.
  */
-int platform_get_irq_optional(struct platform_device *dev, unsigned int num)
+int platform_get_irq_affinity(struct platform_device *dev, unsigned int num,
+			      const struct cpumask **affinity)
 {
 	int ret;
 #ifdef CONFIG_SPARC
@@ -236,8 +248,36 @@ int platform_get_irq_optional(struct platform_device *dev, unsigned int num)
 out:
 	if (WARN(!ret, "0 is an invalid IRQ number\n"))
 		return -EINVAL;
+
+	if (ret > 0 && affinity)
+		*affinity = get_irq_affinity(dev, num);
+
 	return ret;
 }
+EXPORT_SYMBOL_GPL(platform_get_irq_affinity);
+
+/**
+ * platform_get_irq_optional - get an optional IRQ for a device
+ * @dev: platform device
+ * @num: IRQ number index
+ *
+ * Gets an IRQ for a platform device. Device drivers should check the return
+ * value for errors so as to not pass a negative integer value to the
+ * request_irq() APIs. This is the same as platform_get_irq(), except that it
+ * does not print an error message if an IRQ can not be obtained.
+ *
+ * For example::
+ *
+ *		int irq = platform_get_irq_optional(pdev, 0);
+ *		if (irq < 0)
+ *			return irq;
+ *
+ * Return: non-zero IRQ number on success, negative error number on failure.
+ */
+int platform_get_irq_optional(struct platform_device *dev, unsigned int num)
+{
+	return platform_get_irq_affinity(dev, num, NULL);
+}
 EXPORT_SYMBOL_GPL(platform_get_irq_optional);
 
 /**
diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h
index 074754c23d330..ad66333ce85ce 100644
--- a/include/linux/platform_device.h
+++ b/include/linux/platform_device.h
@@ -102,6 +102,8 @@ devm_platform_ioremap_resource_byname(struct platform_device *pdev,
 
 extern int platform_get_irq(struct platform_device *, unsigned int);
 extern int platform_get_irq_optional(struct platform_device *, unsigned int);
+extern int platform_get_irq_affinity(struct platform_device *, unsigned int,
+				     const struct cpumask **);
 extern int platform_irq_count(struct platform_device *);
 extern int devm_platform_get_irqs_affinity(struct platform_device *dev,
 					   struct irq_affinity *affd,
-- 
2.47.3

[PATCH v4 05/26] irqchip/gic-v3: Add FW info retrieval support

[Marc Zyngier]

Plug the new .get_fwspec_info() callback into the GICv3 core driver,
using some of the existing PPI affinity handling infrastructure.

Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/irqchip/irq-gic-v3.c | 53 ++++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index 3de351e66ee84..cf0ba83c6eda6 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -69,6 +69,8 @@ struct gic_chip_data {
 	bool			has_rss;
 	unsigned int		ppi_nr;
 	struct partition_desc	**ppi_descs;
+	struct partition_affinity *parts;
+	unsigned int		nr_parts;
 };
 
 #define T241_CHIPS_MAX		4
@@ -1797,11 +1799,58 @@ static int gic_irq_domain_select(struct irq_domain *d,
 	return d == partition_get_domain(gic_data.ppi_descs[ppi_idx]);
 }
 
+static int gic_irq_get_fwspec_info(struct irq_fwspec *fwspec, struct irq_fwspec_info *info)
+{
+	const struct cpumask *mask = NULL;
+
+	info->flags = 0;
+	info->affinity = NULL;
+
+	/* ACPI is not capable of describing PPI affinity -- yet */
+	if (!is_of_node(fwspec->fwnode))
+		return 0;
+
+	/* If the specifier provides an affinity, use it */
+	if (fwspec->param_count == 4 && fwspec->param[3]) {
+		struct fwnode_handle *fw;
+
+		switch (fwspec->param[0]) {
+		case 1:			/* PPI */
+		case 3:			/* EPPI */
+			break;
+		default:
+			return 0;
+		}
+
+		fw = of_fwnode_handle(of_find_node_by_phandle(fwspec->param[3]));
+		if (!fw)
+			return -ENOENT;
+
+		for (int i = 0; i < gic_data.nr_parts; i++) {
+			if (gic_data.parts[i].partition_id == fw) {
+				mask = &gic_data.parts[i].mask;
+				break;
+			}
+		}
+
+		if (!mask)
+			return -ENOENT;
+	} else {
+		mask = cpu_possible_mask;
+	}
+
+	info->affinity = mask;
+	info->flags = IRQ_FWSPEC_INFO_AFFINITY_VALID;
+
+	return 0;
+}
+
 static const struct irq_domain_ops gic_irq_domain_ops = {
 	.translate = gic_irq_domain_translate,
 	.alloc = gic_irq_domain_alloc,
 	.free = gic_irq_domain_free,
 	.select = gic_irq_domain_select,
+	.get_fwspec_info = gic_irq_get_fwspec_info,
 };
 
 static int partition_domain_translate(struct irq_domain *d,
@@ -1840,6 +1889,7 @@ static int partition_domain_translate(struct irq_domain *d,
 static const struct irq_domain_ops partition_domain_ops = {
 	.translate = partition_domain_translate,
 	.select = gic_irq_domain_select,
+	.get_fwspec_info = gic_irq_get_fwspec_info,
 };
 
 static bool gic_enable_quirk_msm8996(void *data)
@@ -2232,6 +2282,9 @@ static void __init gic_populate_ppi_partitions(struct device_node *gic_node)
 		part_idx++;
 	}
 
+	gic_data.parts = parts;
+	gic_data.nr_parts = nr_parts;
+
 	for (i = 0; i < gic_data.ppi_nr; i++) {
 		unsigned int irq;
 		struct partition_desc *desc;
-- 
2.47.3

[PATCH v4 06/26] irqchip/apple-aic: Add FW info retrieval support

[Marc Zyngier]

Plug the new .get_fwspec_info() callback into the Apple AIC driver,
using some of the existing FIQ affinity handling infrastructure.

Acked-by: Sven Peter <sven@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/irqchip/irq-apple-aic.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/drivers/irqchip/irq-apple-aic.c b/drivers/irqchip/irq-apple-aic.c
index 032d66dceb8ec..cb8b6f40ce8d3 100644
--- a/drivers/irqchip/irq-apple-aic.c
+++ b/drivers/irqchip/irq-apple-aic.c
@@ -651,6 +651,33 @@ static int aic_irq_domain_map(struct irq_domain *id, unsigned int irq,
 	return 0;
 }
 
+static int aic_irq_get_fwspec_info(struct irq_fwspec *fwspec, struct irq_fwspec_info *info)
+{
+	const struct cpumask *mask;
+	u32 intid;
+
+	info->flags = 0;
+	info->affinity = NULL;
+
+	if (fwspec->param[0] != AIC_FIQ)
+		return 0;
+
+	if (fwspec->param_count == 3)
+		intid = fwspec->param[1];
+	else
+		intid = fwspec->param[2];
+
+	if (aic_irqc->fiq_aff[intid])
+		mask = &aic_irqc->fiq_aff[intid]->aff;
+	else
+		mask = cpu_possible_mask;
+
+	info->affinity = mask;
+	info->flags = IRQ_FWSPEC_INFO_AFFINITY_VALID;
+
+	return 0;
+}
+
 static int aic_irq_domain_translate(struct irq_domain *id,
 				    struct irq_fwspec *fwspec,
 				    unsigned long *hwirq,
@@ -753,6 +780,7 @@ static const struct irq_domain_ops aic_irq_domain_ops = {
 	.translate	= aic_irq_domain_translate,
 	.alloc		= aic_irq_domain_alloc,
 	.free		= aic_irq_domain_free,
+	.get_fwspec_info = aic_irq_get_fwspec_info,
 };
 
 /*
-- 
2.47.3

[PATCH v4 07/26] coresight: trbe: Convert to new IRQ affinity retrieval API

[Marc Zyngier]

Now that the relevant interrupt controllers are equipped with
a callback returning the affinity of per-CPU interrupts, switch
the TRBE driver over to this new method.

Acked-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/hwtracing/coresight/coresight-trbe.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c
index 43643d2c5bdd0..8f17160fec442 100644
--- a/drivers/hwtracing/coresight/coresight-trbe.c
+++ b/drivers/hwtracing/coresight/coresight-trbe.c
@@ -1474,9 +1474,10 @@ static void arm_trbe_remove_cpuhp(struct trbe_drvdata *drvdata)
 static int arm_trbe_probe_irq(struct platform_device *pdev,
 			      struct trbe_drvdata *drvdata)
 {
+	const struct cpumask *affinity;
 	int ret;
 
-	drvdata->irq = platform_get_irq(pdev, 0);
+	drvdata->irq = platform_get_irq_affinity(pdev, 0, &affinity);
 	if (drvdata->irq < 0) {
 		pr_err("IRQ not found for the platform device\n");
 		return drvdata->irq;
@@ -1487,8 +1488,7 @@ static int arm_trbe_probe_irq(struct platform_device *pdev,
 		return -EINVAL;
 	}
 
-	if (irq_get_percpu_devid_partition(drvdata->irq, &drvdata->supported_cpus))
-		return -EINVAL;
+	cpumask_copy(&drvdata->supported_cpus, affinity);
 
 	drvdata->handle = alloc_percpu(struct perf_output_handle *);
 	if (!drvdata->handle)
-- 
2.47.3

[PATCH v4 08/26] perf: arm_pmu: Convert to new IRQ affinity retrieval API

[Marc Zyngier]

Now that the relevant interrupt controllers are equipped with
a callback returning the affinity of per-CPU interrupts, switch
the OF side of the ARM PMU driver over to this new method.

Reviewed-by: Jinjie Ruan <ruanjinjie@huawei.com>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/perf/arm_pmu_platform.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/perf/arm_pmu_platform.c b/drivers/perf/arm_pmu_platform.c
index 118170a5cedef..9c0494d8a867a 100644
--- a/drivers/perf/arm_pmu_platform.c
+++ b/drivers/perf/arm_pmu_platform.c
@@ -42,14 +42,13 @@ static int probe_current_pmu(struct arm_pmu *pmu,
 	return ret;
 }
 
-static int pmu_parse_percpu_irq(struct arm_pmu *pmu, int irq)
+static int pmu_parse_percpu_irq(struct arm_pmu *pmu, int irq,
+				const struct cpumask *affinity)
 {
-	int cpu, ret;
 	struct pmu_hw_events __percpu *hw_events = pmu->hw_events;
+	int cpu;
 
-	ret = irq_get_percpu_devid_partition(irq, &pmu->supported_cpus);
-	if (ret)
-		return ret;
+	cpumask_copy(&pmu->supported_cpus, affinity);
 
 	for_each_cpu(cpu, &pmu->supported_cpus)
 		per_cpu(hw_events->irq, cpu) = irq;
@@ -115,9 +114,12 @@ static int pmu_parse_irqs(struct arm_pmu *pmu)
 	}
 
 	if (num_irqs == 1) {
-		int irq = platform_get_irq(pdev, 0);
+		const struct cpumask *affinity;
+		int irq;
+
+		irq = platform_get_irq_affinity(pdev, 0, &affinity);
 		if ((irq > 0) && irq_is_percpu_devid(irq))
-			return pmu_parse_percpu_irq(pmu, irq);
+			return pmu_parse_percpu_irq(pmu, irq, affinity);
 	}
 
 	if (nr_cpu_ids != 1 && !pmu_has_irq_affinity(dev->of_node))
-- 
2.47.3

[PATCH v4 09/26] perf: arm_spe_pmu: Convert to new IRQ affinity retrieval API

[Marc Zyngier]

Now that the relevant interrupt controllers are equipped with
a callback returning the affinity of per-CPU interrupts, switch
the ARM SPE driver over to this new method.

Reviewed-by: Jinjie Ruan <ruanjinjie@huawei.com>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/perf/arm_spe_pmu.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/perf/arm_spe_pmu.c b/drivers/perf/arm_spe_pmu.c
index fa50645feddad..1460b02d20e8b 100644
--- a/drivers/perf/arm_spe_pmu.c
+++ b/drivers/perf/arm_spe_pmu.c
@@ -1287,8 +1287,10 @@ static void arm_spe_pmu_dev_teardown(struct arm_spe_pmu *spe_pmu)
 static int arm_spe_pmu_irq_probe(struct arm_spe_pmu *spe_pmu)
 {
 	struct platform_device *pdev = spe_pmu->pdev;
-	int irq = platform_get_irq(pdev, 0);
+	const struct cpumask *affinity;
+	int irq;
 
+	irq = platform_get_irq_affinity(pdev, 0, &affinity);
 	if (irq < 0)
 		return -ENXIO;
 
@@ -1297,10 +1299,7 @@ static int arm_spe_pmu_irq_probe(struct arm_spe_pmu *spe_pmu)
 		return -EINVAL;
 	}
 
-	if (irq_get_percpu_devid_partition(irq, &spe_pmu->supported_cpus)) {
-		dev_err(&pdev->dev, "failed to get PPI partition (%d)\n", irq);
-		return -EINVAL;
-	}
+	cpumask_copy(&spe_pmu->supported_cpus, affinity);
 
 	spe_pmu->irq = irq;
 	return 0;
-- 
2.47.3

[PATCH v4 10/26] irqchip/gic-v3: Switch high priority PPIs over to handle_percpu_devid_irq()

[Marc Zyngier]

It so appears that handle_percpu_devid_irq() is extremely similar to
handle_percpu_devid_fasteoi_nmi(), and that the differences do no
justify the horrid machinery we have in the GICv3 driver to handle
the flow handler switch.

Let's stick with the standard flow handler, even for NMIs.

Suggested-by: Will Deacon <will@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/irqchip/irq-gic-v3.c | 54 ++----------------------------------
 1 file changed, 2 insertions(+), 52 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index cf0ba83c6eda6..dd2d6d722fc5e 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -230,9 +230,6 @@ static void __init gic_prio_init(void)
 		!cpus_have_group0);
 }
 
-/* rdist_nmi_refs[n] == number of cpus having the rdist interrupt n set as NMI */
-static refcount_t *rdist_nmi_refs;
-
 static struct gic_kvm_info gic_v3_kvm_info __initdata;
 static DEFINE_PER_CPU(bool, has_rss);
 
@@ -608,24 +605,6 @@ static u32 __gic_get_ppi_index(irq_hw_number_t hwirq)
 	}
 }
 
-static u32 __gic_get_rdist_index(irq_hw_number_t hwirq)
-{
-	switch (__get_intid_range(hwirq)) {
-	case SGI_RANGE:
-	case PPI_RANGE:
-		return hwirq;
-	case EPPI_RANGE:
-		return hwirq - EPPI_BASE_INTID + 32;
-	default:
-		unreachable();
-	}
-}
-
-static u32 gic_get_rdist_index(struct irq_data *d)
-{
-	return __gic_get_rdist_index(d->hwirq);
-}
-
 static int gic_irq_nmi_setup(struct irq_data *d)
 {
 	struct irq_desc *desc = irq_to_desc(d->irq);
@@ -646,20 +625,8 @@ static int gic_irq_nmi_setup(struct irq_data *d)
 		return -EINVAL;
 
 	/* desc lock should already be held */
-	if (gic_irq_in_rdist(d)) {
-		u32 idx = gic_get_rdist_index(d);
-
-		/*
-		 * Setting up a percpu interrupt as NMI, only switch handler
-		 * for first NMI
-		 */
-		if (!refcount_inc_not_zero(&rdist_nmi_refs[idx])) {
-			refcount_set(&rdist_nmi_refs[idx], 1);
-			desc->handle_irq = handle_percpu_devid_fasteoi_nmi;
-		}
-	} else {
+	if (!gic_irq_in_rdist(d))
 		desc->handle_irq = handle_fasteoi_nmi;
-	}
 
 	gic_irq_set_prio(d, dist_prio_nmi);
 
@@ -686,15 +653,8 @@ static void gic_irq_nmi_teardown(struct irq_data *d)
 		return;
 
 	/* desc lock should already be held */
-	if (gic_irq_in_rdist(d)) {
-		u32 idx = gic_get_rdist_index(d);
-
-		/* Tearing down NMI, only switch handler for last NMI */
-		if (refcount_dec_and_test(&rdist_nmi_refs[idx]))
-			desc->handle_irq = handle_percpu_devid_irq;
-	} else {
+	if (!gic_irq_in_rdist(d))
 		desc->handle_irq = handle_fasteoi_irq;
-	}
 
 	gic_irq_set_prio(d, dist_prio_irq);
 }
@@ -2080,19 +2040,9 @@ static const struct gic_quirk gic_quirks[] = {
 
 static void gic_enable_nmi_support(void)
 {
-	int i;
-
 	if (!gic_prio_masking_enabled() || nmi_support_forbidden)
 		return;
 
-	rdist_nmi_refs = kcalloc(gic_data.ppi_nr + SGI_NR,
-				 sizeof(*rdist_nmi_refs), GFP_KERNEL);
-	if (!rdist_nmi_refs)
-		return;
-
-	for (i = 0; i < gic_data.ppi_nr + SGI_NR; i++)
-		refcount_set(&rdist_nmi_refs[i], 0);
-
 	pr_info("Pseudo-NMIs enabled using %s ICC_PMR_EL1 synchronisation\n",
 		gic_has_relaxed_pmr_sync() ? "relaxed" : "forced");
 
-- 
2.47.3

[PATCH v4 11/26] genirq: Kill handle_percpu_devid_fasteoi_nmi()

[Marc Zyngier]

There is no in-tree user of this flow handler anymore, so simply
remove it.

Suggested-by: Will Deacon <will@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 include/linux/irq.h |  1 -
 kernel/irq/chip.c   | 25 -------------------------
 2 files changed, 26 deletions(-)

diff --git a/include/linux/irq.h b/include/linux/irq.h
index c67e76fbcc077..b728c18f6ded7 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -655,7 +655,6 @@ extern void handle_bad_irq(struct irq_desc *desc);
 extern void handle_nested_irq(unsigned int irq);
 
 extern void handle_fasteoi_nmi(struct irq_desc *desc);
-extern void handle_percpu_devid_fasteoi_nmi(struct irq_desc *desc);
 
 extern int irq_chip_compose_msi_msg(struct irq_data *data, struct msi_msg *msg);
 extern int irq_chip_pm_get(struct irq_data *data);
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 3ffa0d80ddd19..633e1f67bb6f4 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -929,31 +929,6 @@ void handle_percpu_devid_irq(struct irq_desc *desc)
 		chip->irq_eoi(&desc->irq_data);
 }
 
-/**
- * handle_percpu_devid_fasteoi_nmi - Per CPU local NMI handler with per cpu
- *				     dev ids
- * @desc:	the interrupt description structure for this irq
- *
- * Similar to handle_fasteoi_nmi, but handling the dev_id cookie
- * as a percpu pointer.
- */
-void handle_percpu_devid_fasteoi_nmi(struct irq_desc *desc)
-{
-	struct irq_chip *chip = irq_desc_get_chip(desc);
-	struct irqaction *action = desc->action;
-	unsigned int irq = irq_desc_get_irq(desc);
-	irqreturn_t res;
-
-	__kstat_incr_irqs_this_cpu(desc);
-
-	trace_irq_handler_entry(irq, action);
-	res = action->handler(irq, raw_cpu_ptr(action->percpu_dev_id));
-	trace_irq_handler_exit(irq, action, res);
-
-	if (chip->irq_eoi)
-		chip->irq_eoi(&desc->irq_data);
-}
-
 static void
 __irq_do_set_handler(struct irq_desc *desc, irq_flow_handler_t handle,
 		     int is_chained, const char *name)
-- 
2.47.3

[PATCH v4 12/26] genirq: Merge irqaction::{dev_id,percpu_dev_id}

[Marc Zyngier]

When irqaction::percpu_dev_id was introduced, it was hoped that it
could be part of an anonymous union with dev_id, as the two fields
are mutually exclusive.

However, toolchains used at the time were often showing terrible
support for anonymous unions, breaking the build on a number of
architectures. It was therefore decided to keep the two fields separate
and address this down the line.

14 years later, the compiler dark age is over, and there is universal
support for anonymous unions. Let's get a whole pointer back that can
immediately be spent on something else.

Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 include/linux/interrupt.h | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 51b6484c04934..0ec1a71ab4e84 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -121,8 +121,10 @@ typedef irqreturn_t (*irq_handler_t)(int, void *);
  */
 struct irqaction {
 	irq_handler_t		handler;
-	void			*dev_id;
-	void __percpu		*percpu_dev_id;
+	union {
+		void		*dev_id;
+		void __percpu	*percpu_dev_id;
+	};
 	struct irqaction	*next;
 	irq_handler_t		thread_fn;
 	struct task_struct	*thread;
-- 
2.47.3

[PATCH v4 13/26] genirq: Factor-in percpu irqaction creation

[Marc Zyngier]

Move the code creating a per-cpu irqaction into its own helper, so that
future changes to this code can be kept localised.

At the same time, fix the documentation which appears to say the wrong
thing when it comes to interrupts being automatically enabled
(percpu_devid interrupts never are).

Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 kernel/irq/manage.c | 40 ++++++++++++++++++++++++----------------
 1 file changed, 24 insertions(+), 16 deletions(-)

diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index c94837382037e..d9ddc30678b5d 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -2442,6 +2442,24 @@ int setup_percpu_irq(unsigned int irq, struct irqaction *act)
 	return retval;
 }
 
+static
+struct irqaction *create_percpu_irqaction(irq_handler_t handler, unsigned long flags,
+					  const char *devname, void __percpu *dev_id)
+{
+	struct irqaction *action;
+
+	action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
+	if (!action)
+		return NULL;
+
+	action->handler = handler;
+	action->flags = flags | IRQF_PERCPU | IRQF_NO_SUSPEND;
+	action->name = devname;
+	action->percpu_dev_id = dev_id;
+
+	return action;
+}
+
 /**
  * __request_percpu_irq - allocate a percpu interrupt line
  * @irq:	Interrupt line to allocate
@@ -2450,9 +2468,9 @@ int setup_percpu_irq(unsigned int irq, struct irqaction *act)
  * @devname:	An ascii name for the claiming device
  * @dev_id:	A percpu cookie passed back to the handler function
  *
- * This call allocates interrupt resources and enables the interrupt on the
- * local CPU. If the interrupt is supposed to be enabled on other CPUs, it
- * has to be done on each CPU using enable_percpu_irq().
+ * This call allocates interrupt resources, but doesn't enable the interrupt
+ * on any CPU, as all percpu-devid interrupts are flagged with IRQ_NOAUTOEN.
+ * It has to be done on each CPU using enable_percpu_irq().
  *
  * @dev_id must be globally unique. It is a per-cpu variable, and
  * the handler gets called with the interrupted CPU's instance of
@@ -2477,15 +2495,10 @@ int __request_percpu_irq(unsigned int irq, irq_handler_t handler,
 	if (flags && flags != IRQF_TIMER)
 		return -EINVAL;
 
-	action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
+	action = create_percpu_irqaction(handler, flags, devname, dev_id);
 	if (!action)
 		return -ENOMEM;
 
-	action->handler = handler;
-	action->flags = flags | IRQF_PERCPU | IRQF_NO_SUSPEND;
-	action->name = devname;
-	action->percpu_dev_id = dev_id;
-
 	retval = irq_chip_pm_get(&desc->irq_data);
 	if (retval < 0) {
 		kfree(action);
@@ -2546,16 +2559,11 @@ int request_percpu_nmi(unsigned int irq, irq_handler_t handler,
 	if (irq_is_nmi(desc))
 		return -EINVAL;
 
-	action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
+	action = create_percpu_irqaction(handler, IRQF_NO_THREAD | IRQF_NOBALANCING,
+					 name, dev_id);
 	if (!action)
 		return -ENOMEM;
 
-	action->handler = handler;
-	action->flags = IRQF_PERCPU | IRQF_NO_SUSPEND | IRQF_NO_THREAD
-		| IRQF_NOBALANCING;
-	action->name = name;
-	action->percpu_dev_id = dev_id;
-
 	retval = irq_chip_pm_get(&desc->irq_data);
 	if (retval < 0)
 		goto err_out;
-- 
2.47.3

[PATCH v4 14/26] genirq: Add affinity to percpu_devid interrupt requests

[Marc Zyngier]

Add an affinity field to both the irqaction structure and the interrupt
request primitives. Nothing is making use of it yet, and the only value
used it NULL, which is used as a shorthand for cpu_possible_mask.

This will shortly get used with actual affinities.

Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 include/linux/interrupt.h |  5 +++--
 kernel/irq/manage.c       | 14 ++++++++++----
 2 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 0ec1a71ab4e84..52147d5f432b3 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -125,6 +125,7 @@ struct irqaction {
 		void		*dev_id;
 		void __percpu	*percpu_dev_id;
 	};
+	const struct cpumask	*affinity;
 	struct irqaction	*next;
 	irq_handler_t		thread_fn;
 	struct task_struct	*thread;
@@ -181,7 +182,7 @@ request_any_context_irq(unsigned int irq, irq_handler_t handler,
 extern int __must_check
 __request_percpu_irq(unsigned int irq, irq_handler_t handler,
 		     unsigned long flags, const char *devname,
-		     void __percpu *percpu_dev_id);
+		     const cpumask_t *affinity, void __percpu *percpu_dev_id);
 
 extern int __must_check
 request_nmi(unsigned int irq, irq_handler_t handler, unsigned long flags,
@@ -192,7 +193,7 @@ request_percpu_irq(unsigned int irq, irq_handler_t handler,
 		   const char *devname, void __percpu *percpu_dev_id)
 {
 	return __request_percpu_irq(irq, handler, 0,
-				    devname, percpu_dev_id);
+				    devname, NULL, percpu_dev_id);
 }
 
 extern int __must_check
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index d9ddc30678b5d..5f4c651677436 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -2444,10 +2444,14 @@ int setup_percpu_irq(unsigned int irq, struct irqaction *act)
 
 static
 struct irqaction *create_percpu_irqaction(irq_handler_t handler, unsigned long flags,
-					  const char *devname, void __percpu *dev_id)
+					  const char *devname, const cpumask_t *affinity,
+					  void __percpu *dev_id)
 {
 	struct irqaction *action;
 
+	if (!affinity)
+		affinity = cpu_possible_mask;
+
 	action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
 	if (!action)
 		return NULL;
@@ -2456,6 +2460,7 @@ struct irqaction *create_percpu_irqaction(irq_handler_t handler, unsigned long f
 	action->flags = flags | IRQF_PERCPU | IRQF_NO_SUSPEND;
 	action->name = devname;
 	action->percpu_dev_id = dev_id;
+	action->affinity = affinity;
 
 	return action;
 }
@@ -2466,6 +2471,7 @@ struct irqaction *create_percpu_irqaction(irq_handler_t handler, unsigned long f
  * @handler:	Function to be called when the IRQ occurs.
  * @flags:	Interrupt type flags (IRQF_TIMER only)
  * @devname:	An ascii name for the claiming device
+ * @affinity:	A cpumask describing the target CPUs for this interrupt
  * @dev_id:	A percpu cookie passed back to the handler function
  *
  * This call allocates interrupt resources, but doesn't enable the interrupt
@@ -2478,7 +2484,7 @@ struct irqaction *create_percpu_irqaction(irq_handler_t handler, unsigned long f
  */
 int __request_percpu_irq(unsigned int irq, irq_handler_t handler,
 			 unsigned long flags, const char *devname,
-			 void __percpu *dev_id)
+			 const cpumask_t *affinity, void __percpu *dev_id)
 {
 	struct irqaction *action;
 	struct irq_desc *desc;
@@ -2495,7 +2501,7 @@ int __request_percpu_irq(unsigned int irq, irq_handler_t handler,
 	if (flags && flags != IRQF_TIMER)
 		return -EINVAL;
 
-	action = create_percpu_irqaction(handler, flags, devname, dev_id);
+	action = create_percpu_irqaction(handler, flags, devname, affinity, dev_id);
 	if (!action)
 		return -ENOMEM;
 
@@ -2560,7 +2566,7 @@ int request_percpu_nmi(unsigned int irq, irq_handler_t handler,
 		return -EINVAL;
 
 	action = create_percpu_irqaction(handler, IRQF_NO_THREAD | IRQF_NOBALANCING,
-					 name, dev_id);
+					 name, NULL, dev_id);
 	if (!action)
 		return -ENOMEM;
 
-- 
2.47.3

[PATCH v4 15/26] genirq: Update request_percpu_nmi() to take an affinity

[Marc Zyngier]

Continue spreading the notion of affinity to the percpu interrupt
request code by updating the call sites that use request_percpu_nmi()
(all two of them) to take an affinity pointer. This pointer is
firmly NULL for now.

Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 arch/arm64/kernel/smp.c   |  2 +-
 drivers/perf/arm_pmu.c    |  2 +-
 include/linux/interrupt.h |  4 ++--
 kernel/irq/manage.c       | 12 +++++++-----
 4 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 68cea3a4a35ca..6fb838eee2e7d 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -1094,7 +1094,7 @@ static void ipi_setup_sgi(int ipi)
 	irq = ipi_irq_base + ipi;
 
 	if (ipi_should_be_nmi(ipi)) {
-		err = request_percpu_nmi(irq, ipi_handler, "IPI", &irq_stat);
+		err = request_percpu_nmi(irq, ipi_handler, "IPI", NULL, &irq_stat);
 		WARN(err, "Could not request IRQ %d as NMI, err=%d\n", irq, err);
 	} else {
 		err = request_percpu_irq(irq, ipi_handler, "IPI", &irq_stat);
diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
index 5c310e803dd78..22c601b46c858 100644
--- a/drivers/perf/arm_pmu.c
+++ b/drivers/perf/arm_pmu.c
@@ -659,7 +659,7 @@ int armpmu_request_irq(int irq, int cpu)
 			irq_ops = &pmunmi_ops;
 		}
 	} else if (armpmu_count_irq_users(irq) == 0) {
-		err = request_percpu_nmi(irq, handler, "arm-pmu", &cpu_armpmu);
+		err = request_percpu_nmi(irq, handler, "arm-pmu", NULL, &cpu_armpmu);
 
 		/* If cannot get an NMI, get a normal interrupt */
 		if (err) {
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 52147d5f432b3..81506ab759b81 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -197,8 +197,8 @@ request_percpu_irq(unsigned int irq, irq_handler_t handler,
 }
 
 extern int __must_check
-request_percpu_nmi(unsigned int irq, irq_handler_t handler,
-		   const char *devname, void __percpu *dev);
+request_percpu_nmi(unsigned int irq, irq_handler_t handler, const char *name,
+		   const struct cpumask *affinity, void __percpu *dev_id);
 
 extern const void *free_irq(unsigned int, void *);
 extern void free_percpu_irq(unsigned int, void __percpu *);
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 5f4c651677436..b1a3140e5f3c9 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -2527,6 +2527,7 @@ EXPORT_SYMBOL_GPL(__request_percpu_irq);
  * @irq:	Interrupt line to allocate
  * @handler:	Function to be called when the IRQ occurs.
  * @name:	An ascii name for the claiming device
+ * @affinity:	A cpumask describing the target CPUs for this interrupt
  * @dev_id:	A percpu cookie passed back to the handler function
  *
  * This call allocates interrupt resources for a per CPU NMI. Per CPU NMIs
@@ -2543,8 +2544,8 @@ EXPORT_SYMBOL_GPL(__request_percpu_irq);
  * If the interrupt line cannot be used to deliver NMIs, function
  * will fail returning a negative value.
  */
-int request_percpu_nmi(unsigned int irq, irq_handler_t handler,
-		       const char *name, void __percpu *dev_id)
+int request_percpu_nmi(unsigned int irq, irq_handler_t handler, const char *name,
+		       const struct cpumask *affinity, void __percpu *dev_id)
 {
 	struct irqaction *action;
 	struct irq_desc *desc;
@@ -2561,12 +2562,13 @@ int request_percpu_nmi(unsigned int irq, irq_handler_t handler,
 	    !irq_supports_nmi(desc))
 		return -EINVAL;
 
-	/* The line cannot already be NMI */
-	if (irq_is_nmi(desc))
+	/* The line cannot be NMI already if the new request covers all CPUs */
+	if (irq_is_nmi(desc) &&
+	    (!affinity || cpumask_equal(affinity, cpu_possible_mask)))
 		return -EINVAL;
 
 	action = create_percpu_irqaction(handler, IRQF_NO_THREAD | IRQF_NOBALANCING,
-					 name, NULL, dev_id);
+					 name, affinity, dev_id);
 	if (!action)
 		return -ENOMEM;
 
-- 
2.47.3

[PATCH v4 16/26] genirq: Allow per-cpu interrupt sharing for non-overlapping affinities

[Marc Zyngier]

Interrupt sharing for percpu-devid interrupts is forbidden, and
for good reasons. These are interrupts generated *from* a CPU and
handled by itself (timer, for example). Nobody in their right mind
would put two devices on the same pin (and if they have, they get to
keep the pieces...).

But this also prevents more benign cases, where devices are connected
to groups of CPUs, and for which the affinities are not overlapping.
Effectively, the only thing they share is the interrupt number, and
nothing else.

Let's tweak the definition of IRQF_SHARED applied to percpu_devid
interrupts to allow this particular case. This results in extra
validation at the point of the interrupt being setup and freed,
as well as a tiny bit of extra complexity for interrupts at handling
time (to pick the correct irqaction).

Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 kernel/irq/chip.c   |  8 ++++--
 kernel/irq/manage.c | 67 +++++++++++++++++++++++++++++++++++++--------
 2 files changed, 61 insertions(+), 14 deletions(-)

diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 633e1f67bb6f4..19e0a87a2663e 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -897,8 +897,9 @@ void handle_percpu_irq(struct irq_desc *desc)
 void handle_percpu_devid_irq(struct irq_desc *desc)
 {
 	struct irq_chip *chip = irq_desc_get_chip(desc);
-	struct irqaction *action = desc->action;
 	unsigned int irq = irq_desc_get_irq(desc);
+	unsigned int cpu = smp_processor_id();
+	struct irqaction *action;
 	irqreturn_t res;
 
 	/*
@@ -910,12 +911,15 @@ void handle_percpu_devid_irq(struct irq_desc *desc)
 	if (chip->irq_ack)
 		chip->irq_ack(&desc->irq_data);
 
+	for (action = desc->action; action; action = action->next)
+		if (cpumask_test_cpu(cpu, action->affinity))
+			break;
+
 	if (likely(action)) {
 		trace_irq_handler_entry(irq, action);
 		res = action->handler(irq, raw_cpu_ptr(action->percpu_dev_id));
 		trace_irq_handler_exit(irq, action, res);
 	} else {
-		unsigned int cpu = smp_processor_id();
 		bool enabled = cpumask_test_cpu(cpu, desc->percpu_enabled);
 
 		if (enabled)
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index b1a3140e5f3c9..ea3dbf6fee194 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -1418,6 +1418,19 @@ setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
 	return 0;
 }
 
+static bool valid_percpu_irqaction(struct irqaction *old, struct irqaction *new)
+{
+	do {
+		if (cpumask_intersects(old->affinity, new->affinity) ||
+		    old->percpu_dev_id == new->percpu_dev_id)
+			return false;
+
+		old = old->next;
+	} while (old);
+
+	return true;
+}
+
 /*
  * Internal function to register an irqaction - typically used to
  * allocate special interrupts that are part of the architecture.
@@ -1438,6 +1451,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 	struct irqaction *old, **old_ptr;
 	unsigned long flags, thread_mask = 0;
 	int ret, nested, shared = 0;
+	bool per_cpu_devid;
 
 	if (!desc)
 		return -EINVAL;
@@ -1447,6 +1461,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 	if (!try_module_get(desc->owner))
 		return -ENODEV;
 
+	per_cpu_devid = irq_settings_is_per_cpu_devid(desc);
+
 	new->irq = irq;
 
 	/*
@@ -1554,13 +1570,20 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 		 */
 		unsigned int oldtype;
 
-		if (irq_is_nmi(desc)) {
+		if (irq_is_nmi(desc) && !per_cpu_devid) {
 			pr_err("Invalid attempt to share NMI for %s (irq %d) on irqchip %s.\n",
 				new->name, irq, desc->irq_data.chip->name);
 			ret = -EINVAL;
 			goto out_unlock;
 		}
 
+		if (per_cpu_devid && !valid_percpu_irqaction(old, new)) {
+			pr_err("Overlapping affinities for %s (irq %d) on irqchip %s.\n",
+				new->name, irq, desc->irq_data.chip->name);
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+
 		/*
 		 * If nobody did set the configuration before, inherit
 		 * the one provided by the requester.
@@ -1711,7 +1734,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 		if (!(new->flags & IRQF_NO_AUTOEN) &&
 		    irq_settings_can_autoenable(desc)) {
 			irq_startup(desc, IRQ_RESEND, IRQ_START_COND);
-		} else {
+		} else if (!per_cpu_devid) {
 			/*
 			 * Shared interrupts do not go well with disabling
 			 * auto enable. The sharing interrupt might request
@@ -2346,7 +2369,7 @@ void disable_percpu_nmi(unsigned int irq)
 static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_id)
 {
 	struct irq_desc *desc = irq_to_desc(irq);
-	struct irqaction *action;
+	struct irqaction *action, **action_ptr;
 
 	WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
 
@@ -2354,21 +2377,33 @@ static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_
 		return NULL;
 
 	scoped_guard(raw_spinlock_irqsave, &desc->lock) {
-		action = desc->action;
-		if (!action || action->percpu_dev_id != dev_id) {
-			WARN(1, "Trying to free already-free IRQ %d\n", irq);
-			return NULL;
+		action_ptr = &desc->action;
+		for (;;) {
+			action = *action_ptr;
+
+			if (!action) {
+				WARN(1, "Trying to free already-free IRQ %d\n", irq);
+				return NULL;
+			}
+
+			if (action->percpu_dev_id == dev_id)
+				break;
+
+			action_ptr = &action->next;
 		}
 
-		if (!cpumask_empty(desc->percpu_enabled)) {
-			WARN(1, "percpu IRQ %d still enabled on CPU%d!\n",
-			     irq, cpumask_first(desc->percpu_enabled));
+		if (cpumask_intersects(desc->percpu_enabled, action->affinity)) {
+			WARN(1, "percpu IRQ %d still enabled on CPU%d!\n", irq,
+			     cpumask_first_and(desc->percpu_enabled, action->affinity));
 			return NULL;
 		}
 
 		/* Found it - now remove it from the list of entries: */
-		desc->action = NULL;
-		desc->istate &= ~IRQS_NMI;
+		*action_ptr = action->next;
+
+		/* Demote from NMI if we killed the last action */
+		if (!desc->action)
+			desc->istate &= ~IRQS_NMI;
 	}
 
 	unregister_handler_proc(irq, action);
@@ -2462,6 +2497,14 @@ struct irqaction *create_percpu_irqaction(irq_handler_t handler, unsigned long f
 	action->percpu_dev_id = dev_id;
 	action->affinity = affinity;
 
+	/*
+	 * We allow some form of sharing for non-overlapping affinity
+	 * masks. Obviously, covering all CPUs prevents any sharing
+	 * the first place.
+	 */
+	if (!cpumask_equal(affinity, cpu_possible_mask))
+		action->flags |= IRQF_SHARED;
+
 	return action;
 }
 
-- 
2.47.3

[PATCH v4 17/26] genirq: Add request_percpu_irq_affinity() helper

[Marc Zyngier]

While it would be nice to simply make request_percpu_irq() take
an affinity mask, the churn is likely to be on the irritating side
given that most drivers do not give a damn about affinities.

So take the more innocuous path to provide a helper that parallels
request_percpu_irq(), with an affinity as a bonus argument.

Yes, request_percpu_irq_affinity() is a bit of a mouthful.

Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 include/linux/interrupt.h | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 81506ab759b81..fa62ab556ee32 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -196,6 +196,15 @@ request_percpu_irq(unsigned int irq, irq_handler_t handler,
 				    devname, NULL, percpu_dev_id);
 }
 
+static inline int __must_check
+request_percpu_irq_affinity(unsigned int irq, irq_handler_t handler,
+			    const char *devname, const cpumask_t *affinity,
+			    void __percpu *percpu_dev_id)
+{
+	return __request_percpu_irq(irq, handler, 0,
+				    devname, affinity, percpu_dev_id);
+}
+
 extern int __must_check
 request_percpu_nmi(unsigned int irq, irq_handler_t handler, const char *name,
 		   const struct cpumask *affinity, void __percpu *dev_id);
-- 
2.47.3

[PATCH v4 18/26] perf: arm_pmu: Request specific affinities for percpu NMI/IRQ

[Marc Zyngier]

From: Will Deacon <will@kernel.org>

Let the PMU driver request both NMI and normal IRQs with an affinity
mask matching the PMU affinity.

Signed-off-by: Will Deacon <will@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/perf/arm_pmu.c          | 44 +++++++++++++++++++--------------
 drivers/perf/arm_pmu_acpi.c     |  2 +-
 drivers/perf/arm_pmu_platform.c |  4 +--
 include/linux/perf/arm_pmu.h    |  4 +--
 4 files changed, 31 insertions(+), 23 deletions(-)

diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
index 22c601b46c858..959ceb3d1f556 100644
--- a/drivers/perf/arm_pmu.c
+++ b/drivers/perf/arm_pmu.c
@@ -26,7 +26,8 @@
 
 #include <asm/irq_regs.h>
 
-static int armpmu_count_irq_users(const int irq);
+static int armpmu_count_irq_users(const struct cpumask *affinity,
+				  const int irq);
 
 struct pmu_irq_ops {
 	void (*enable_pmuirq)(unsigned int irq);
@@ -64,7 +65,9 @@ static void armpmu_enable_percpu_pmuirq(unsigned int irq)
 static void armpmu_free_percpu_pmuirq(unsigned int irq, int cpu,
 				   void __percpu *devid)
 {
-	if (armpmu_count_irq_users(irq) == 1)
+	struct arm_pmu *armpmu = *per_cpu_ptr((void * __percpu *)devid, cpu);
+
+	if (armpmu_count_irq_users(&armpmu->supported_cpus, irq) == 1)
 		free_percpu_irq(irq, devid);
 }
 
@@ -89,7 +92,9 @@ static void armpmu_disable_percpu_pmunmi(unsigned int irq)
 static void armpmu_free_percpu_pmunmi(unsigned int irq, int cpu,
 				      void __percpu *devid)
 {
-	if (armpmu_count_irq_users(irq) == 1)
+	struct arm_pmu *armpmu = *per_cpu_ptr((void * __percpu *)devid, cpu);
+
+	if (armpmu_count_irq_users(&armpmu->supported_cpus, irq) == 1)
 		free_percpu_nmi(irq, devid);
 }
 
@@ -580,11 +585,11 @@ static const struct attribute_group armpmu_common_attr_group = {
 	.attrs = armpmu_common_attrs,
 };
 
-static int armpmu_count_irq_users(const int irq)
+static int armpmu_count_irq_users(const struct cpumask *affinity, const int irq)
 {
 	int cpu, count = 0;
 
-	for_each_possible_cpu(cpu) {
+	for_each_cpu(cpu, affinity) {
 		if (per_cpu(cpu_irq, cpu) == irq)
 			count++;
 	}
@@ -592,12 +597,13 @@ static int armpmu_count_irq_users(const int irq)
 	return count;
 }
 
-static const struct pmu_irq_ops *armpmu_find_irq_ops(int irq)
+static const struct pmu_irq_ops *
+armpmu_find_irq_ops(const struct cpumask *affinity, int irq)
 {
 	const struct pmu_irq_ops *ops = NULL;
 	int cpu;
 
-	for_each_possible_cpu(cpu) {
+	for_each_cpu(cpu, affinity) {
 		if (per_cpu(cpu_irq, cpu) != irq)
 			continue;
 
@@ -609,22 +615,25 @@ static const struct pmu_irq_ops *armpmu_find_irq_ops(int irq)
 	return ops;
 }
 
-void armpmu_free_irq(int irq, int cpu)
+void armpmu_free_irq(struct arm_pmu * __percpu *armpmu, int irq, int cpu)
 {
 	if (per_cpu(cpu_irq, cpu) == 0)
 		return;
 	if (WARN_ON(irq != per_cpu(cpu_irq, cpu)))
 		return;
 
-	per_cpu(cpu_irq_ops, cpu)->free_pmuirq(irq, cpu, &cpu_armpmu);
+	per_cpu(cpu_irq_ops, cpu)->free_pmuirq(irq, cpu, armpmu);
 
 	per_cpu(cpu_irq, cpu) = 0;
 	per_cpu(cpu_irq_ops, cpu) = NULL;
 }
 
-int armpmu_request_irq(int irq, int cpu)
+int armpmu_request_irq(struct arm_pmu * __percpu *pcpu_armpmu, int irq, int cpu)
 {
 	int err = 0;
+	struct arm_pmu **armpmu = per_cpu_ptr(pcpu_armpmu, cpu);
+	const struct cpumask *affinity = *armpmu ? &(*armpmu)->supported_cpus :
+						   cpu_possible_mask; /* ACPI */
 	const irq_handler_t handler = armpmu_dispatch_irq;
 	const struct pmu_irq_ops *irq_ops;
 
@@ -646,25 +655,24 @@ int armpmu_request_irq(int irq, int cpu)
 			    IRQF_NOBALANCING | IRQF_NO_AUTOEN |
 			    IRQF_NO_THREAD;
 
-		err = request_nmi(irq, handler, irq_flags, "arm-pmu",
-				  per_cpu_ptr(&cpu_armpmu, cpu));
+		err = request_nmi(irq, handler, irq_flags, "arm-pmu", armpmu);
 
 		/* If cannot get an NMI, get a normal interrupt */
 		if (err) {
 			err = request_irq(irq, handler, irq_flags, "arm-pmu",
-					  per_cpu_ptr(&cpu_armpmu, cpu));
+					  armpmu);
 			irq_ops = &pmuirq_ops;
 		} else {
 			has_nmi = true;
 			irq_ops = &pmunmi_ops;
 		}
-	} else if (armpmu_count_irq_users(irq) == 0) {
-		err = request_percpu_nmi(irq, handler, "arm-pmu", NULL, &cpu_armpmu);
+	} else if (armpmu_count_irq_users(affinity, irq) == 0) {
+		err = request_percpu_nmi(irq, handler, "arm-pmu", affinity, pcpu_armpmu);
 
 		/* If cannot get an NMI, get a normal interrupt */
 		if (err) {
-			err = request_percpu_irq(irq, handler, "arm-pmu",
-						 &cpu_armpmu);
+			err = request_percpu_irq_affinity(irq, handler, "arm-pmu",
+							  affinity, pcpu_armpmu);
 			irq_ops = &percpu_pmuirq_ops;
 		} else {
 			has_nmi = true;
@@ -672,7 +680,7 @@ int armpmu_request_irq(int irq, int cpu)
 		}
 	} else {
 		/* Per cpudevid irq was already requested by another CPU */
-		irq_ops = armpmu_find_irq_ops(irq);
+		irq_ops = armpmu_find_irq_ops(affinity, irq);
 
 		if (WARN_ON(!irq_ops))
 			err = -EINVAL;
diff --git a/drivers/perf/arm_pmu_acpi.c b/drivers/perf/arm_pmu_acpi.c
index 05dda19c5359a..e80f76d95e68b 100644
--- a/drivers/perf/arm_pmu_acpi.c
+++ b/drivers/perf/arm_pmu_acpi.c
@@ -218,7 +218,7 @@ static int arm_pmu_acpi_parse_irqs(void)
 		 * them with their PMUs.
 		 */
 		per_cpu(pmu_irqs, cpu) = irq;
-		err = armpmu_request_irq(irq, cpu);
+		err = armpmu_request_irq(&probed_pmus, irq, cpu);
 		if (err)
 			goto out_err;
 	}
diff --git a/drivers/perf/arm_pmu_platform.c b/drivers/perf/arm_pmu_platform.c
index 9c0494d8a867a..1c9e50a132015 100644
--- a/drivers/perf/arm_pmu_platform.c
+++ b/drivers/perf/arm_pmu_platform.c
@@ -165,7 +165,7 @@ static int armpmu_request_irqs(struct arm_pmu *armpmu)
 		if (!irq)
 			continue;
 
-		err = armpmu_request_irq(irq, cpu);
+		err = armpmu_request_irq(&hw_events->percpu_pmu, irq, cpu);
 		if (err)
 			break;
 	}
@@ -181,7 +181,7 @@ static void armpmu_free_irqs(struct arm_pmu *armpmu)
 	for_each_cpu(cpu, &armpmu->supported_cpus) {
 		int irq = per_cpu(hw_events->irq, cpu);
 
-		armpmu_free_irq(irq, cpu);
+		armpmu_free_irq(&hw_events->percpu_pmu, irq, cpu);
 	}
 }
 
diff --git a/include/linux/perf/arm_pmu.h b/include/linux/perf/arm_pmu.h
index 93c9a26492fcf..6690bd77aa4ee 100644
--- a/include/linux/perf/arm_pmu.h
+++ b/include/linux/perf/arm_pmu.h
@@ -190,8 +190,8 @@ bool arm_pmu_irq_is_nmi(void);
 struct arm_pmu *armpmu_alloc(void);
 void armpmu_free(struct arm_pmu *pmu);
 int armpmu_register(struct arm_pmu *pmu);
-int armpmu_request_irq(int irq, int cpu);
-void armpmu_free_irq(int irq, int cpu);
+int armpmu_request_irq(struct arm_pmu * __percpu *armpmu, int irq, int cpu);
+void armpmu_free_irq(struct arm_pmu * __percpu *armpmu, int irq, int cpu);
 
 #define ARMV8_PMU_PDEV_NAME "armv8-pmu"
 
-- 
2.47.3

[PATCH v4 19/26] perf: arm_spe_pmu: Request specific affinities for percpu IRQ

[Marc Zyngier]

Let the SPE driver request IRQs with an affinity mask matching
the SPE implementation affinity.

Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/perf/arm_spe_pmu.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/perf/arm_spe_pmu.c b/drivers/perf/arm_spe_pmu.c
index 1460b02d20e8b..87908f0712c0c 100644
--- a/drivers/perf/arm_spe_pmu.c
+++ b/drivers/perf/arm_spe_pmu.c
@@ -1259,8 +1259,8 @@ static int arm_spe_pmu_dev_init(struct arm_spe_pmu *spe_pmu)
 		return -ENXIO;
 
 	/* Request our PPIs (note that the IRQ is still disabled) */
-	ret = request_percpu_irq(spe_pmu->irq, arm_spe_pmu_irq_handler, DRVNAME,
-				 spe_pmu->handle);
+	ret = request_percpu_irq_affinity(spe_pmu->irq, arm_spe_pmu_irq_handler,
+					  DRVNAME, mask, spe_pmu->handle);
 	if (ret)
 		return ret;
 
-- 
2.47.3

[PATCH v4 20/26] coresight: trbe: Request specific affinities for percpu IRQ

[Marc Zyngier]

Let the TRBE driver request IRQs with an affinity mask matching
the TRBE implementation affinity.

Acked-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/hwtracing/coresight/coresight-trbe.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c
index 8f17160fec442..9f64f463339d6 100644
--- a/drivers/hwtracing/coresight/coresight-trbe.c
+++ b/drivers/hwtracing/coresight/coresight-trbe.c
@@ -1494,7 +1494,8 @@ static int arm_trbe_probe_irq(struct platform_device *pdev,
 	if (!drvdata->handle)
 		return -ENOMEM;
 
-	ret = request_percpu_irq(drvdata->irq, arm_trbe_irq_handler, DRVNAME, drvdata->handle);
+	ret = request_percpu_irq_affinity(drvdata->irq, arm_trbe_irq_handler, DRVNAME,
+					  affinity, drvdata->handle);
 	if (ret) {
 		free_percpu(drvdata->handle);
 		return ret;
-- 
2.47.3

[PATCH v4 21/26] irqchip/gic-v3: Drop support for custom PPI partitions

[Marc Zyngier]

The only thing getting in the way of correctly handling PPIs the way
they were intended is the GICv3 hack that deals with PPI partitions.

Remove that code, allowing the common code to kick in.

Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/irqchip/Kconfig      |   1 -
 drivers/irqchip/irq-gic-v3.c | 133 +++--------------------------------
 2 files changed, 8 insertions(+), 126 deletions(-)

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index a61c6dc63c29c..648b3618fc784 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -36,7 +36,6 @@ config GIC_NON_BANKED
 config ARM_GIC_V3
 	bool
 	select IRQ_DOMAIN_HIERARCHY
-	select PARTITION_PERCPU
 	select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
 	select HAVE_ARM_SMCCC_DISCOVERY
 	select IRQ_MSI_IOMMU
diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index dd2d6d722fc5e..6607ab58f72e6 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -26,7 +26,6 @@
 #include <linux/irqchip/arm-gic-common.h>
 #include <linux/irqchip/arm-gic-v3.h>
 #include <linux/irqchip/arm-gic-v3-prio.h>
-#include <linux/irqchip/irq-partition-percpu.h>
 #include <linux/bitfield.h>
 #include <linux/bits.h>
 #include <linux/arm-smccc.h>
@@ -46,8 +45,6 @@ static u8 dist_prio_nmi __ro_after_init = GICV3_PRIO_NMI;
 #define FLAGS_WORKAROUND_ASR_ERRATUM_8601001	(1ULL << 2)
 #define FLAGS_WORKAROUND_INSECURE		(1ULL << 3)
 
-#define GIC_IRQ_TYPE_PARTITION	(GIC_IRQ_TYPE_LPI + 1)
-
 static struct cpumask broken_rdists __read_mostly __maybe_unused;
 
 struct redist_region {
@@ -68,11 +65,15 @@ struct gic_chip_data {
 	u64			flags;
 	bool			has_rss;
 	unsigned int		ppi_nr;
-	struct partition_desc	**ppi_descs;
 	struct partition_affinity *parts;
 	unsigned int		nr_parts;
 };
 
+struct partition_affinity {
+	cpumask_t			mask;
+	struct fwnode_handle		*partition_id;
+};
+
 #define T241_CHIPS_MAX		4
 static void __iomem *t241_dist_base_alias[T241_CHIPS_MAX] __read_mostly;
 static DEFINE_STATIC_KEY_FALSE(gic_nvidia_t241_erratum);
@@ -593,18 +594,6 @@ static void gic_irq_set_prio(struct irq_data *d, u8 prio)
 	writeb_relaxed(prio, base + offset + index);
 }
 
-static u32 __gic_get_ppi_index(irq_hw_number_t hwirq)
-{
-	switch (__get_intid_range(hwirq)) {
-	case PPI_RANGE:
-		return hwirq - 16;
-	case EPPI_RANGE:
-		return hwirq - EPPI_BASE_INTID + 16;
-	default:
-		unreachable();
-	}
-}
-
 static int gic_irq_nmi_setup(struct irq_data *d)
 {
 	struct irq_desc *desc = irq_to_desc(d->irq);
@@ -1628,13 +1617,6 @@ static int gic_irq_domain_translate(struct irq_domain *d,
 		case GIC_IRQ_TYPE_LPI:	/* LPI */
 			*hwirq = fwspec->param[1];
 			break;
-		case GIC_IRQ_TYPE_PARTITION:
-			*hwirq = fwspec->param[1];
-			if (fwspec->param[1] >= 16)
-				*hwirq += EPPI_BASE_INTID - 16;
-			else
-				*hwirq += 16;
-			break;
 		default:
 			return -EINVAL;
 		}
@@ -1643,10 +1625,8 @@ static int gic_irq_domain_translate(struct irq_domain *d,
 
 		/*
 		 * Make it clear that broken DTs are... broken.
-		 * Partitioned PPIs are an unfortunate exception.
 		 */
-		WARN_ON(*type == IRQ_TYPE_NONE &&
-			fwspec->param[0] != GIC_IRQ_TYPE_PARTITION);
+		WARN_ON(*type == IRQ_TYPE_NONE);
 		return 0;
 	}
 
@@ -1703,33 +1683,12 @@ static void gic_irq_domain_free(struct irq_domain *domain, unsigned int virq,
 	}
 }
 
-static bool fwspec_is_partitioned_ppi(struct irq_fwspec *fwspec,
-				      irq_hw_number_t hwirq)
-{
-	enum gic_intid_range range;
-
-	if (!gic_data.ppi_descs)
-		return false;
-
-	if (!is_of_node(fwspec->fwnode))
-		return false;
-
-	if (fwspec->param_count < 4 || !fwspec->param[3])
-		return false;
-
-	range = __get_intid_range(hwirq);
-	if (range != PPI_RANGE && range != EPPI_RANGE)
-		return false;
-
-	return true;
-}
-
 static int gic_irq_domain_select(struct irq_domain *d,
 				 struct irq_fwspec *fwspec,
 				 enum irq_domain_bus_token bus_token)
 {
-	unsigned int type, ppi_idx;
 	irq_hw_number_t hwirq;
+	unsigned int type;
 	int ret;
 
 	/* Not for us */
@@ -1748,15 +1707,7 @@ static int gic_irq_domain_select(struct irq_domain *d,
 	if (WARN_ON_ONCE(ret))
 		return 0;
 
-	if (!fwspec_is_partitioned_ppi(fwspec, hwirq))
-		return d == gic_data.domain;
-
-	/*
-	 * If this is a PPI and we have a 4th (non-null) parameter,
-	 * then we need to match the partition domain.
-	 */
-	ppi_idx = __gic_get_ppi_index(hwirq);
-	return d == partition_get_domain(gic_data.ppi_descs[ppi_idx]);
+	return d == gic_data.domain;
 }
 
 static int gic_irq_get_fwspec_info(struct irq_fwspec *fwspec, struct irq_fwspec_info *info)
@@ -1813,45 +1764,6 @@ static const struct irq_domain_ops gic_irq_domain_ops = {
 	.get_fwspec_info = gic_irq_get_fwspec_info,
 };
 
-static int partition_domain_translate(struct irq_domain *d,
-				      struct irq_fwspec *fwspec,
-				      unsigned long *hwirq,
-				      unsigned int *type)
-{
-	unsigned long ppi_intid;
-	struct device_node *np;
-	unsigned int ppi_idx;
-	int ret;
-
-	if (!gic_data.ppi_descs)
-		return -ENOMEM;
-
-	np = of_find_node_by_phandle(fwspec->param[3]);
-	if (WARN_ON(!np))
-		return -EINVAL;
-
-	ret = gic_irq_domain_translate(d, fwspec, &ppi_intid, type);
-	if (WARN_ON_ONCE(ret))
-		return 0;
-
-	ppi_idx = __gic_get_ppi_index(ppi_intid);
-	ret = partition_translate_id(gic_data.ppi_descs[ppi_idx],
-				     of_fwnode_handle(np));
-	if (ret < 0)
-		return ret;
-
-	*hwirq = ret;
-	*type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
-
-	return 0;
-}
-
-static const struct irq_domain_ops partition_domain_ops = {
-	.translate = partition_domain_translate,
-	.select = gic_irq_domain_select,
-	.get_fwspec_info = gic_irq_get_fwspec_info,
-};
-
 static bool gic_enable_quirk_msm8996(void *data)
 {
 	struct gic_chip_data *d = data;
@@ -2174,12 +2086,7 @@ static void __init gic_populate_ppi_partitions(struct device_node *gic_node)
 	if (!parts_node)
 		return;
 
-	gic_data.ppi_descs = kcalloc(gic_data.ppi_nr, sizeof(*gic_data.ppi_descs), GFP_KERNEL);
-	if (!gic_data.ppi_descs)
-		goto out_put_node;
-
 	nr_parts = of_get_child_count(parts_node);
-
 	if (!nr_parts)
 		goto out_put_node;
 
@@ -2235,30 +2142,6 @@ static void __init gic_populate_ppi_partitions(struct device_node *gic_node)
 	gic_data.parts = parts;
 	gic_data.nr_parts = nr_parts;
 
-	for (i = 0; i < gic_data.ppi_nr; i++) {
-		unsigned int irq;
-		struct partition_desc *desc;
-		struct irq_fwspec ppi_fwspec = {
-			.fwnode		= gic_data.fwnode,
-			.param_count	= 3,
-			.param		= {
-				[0]	= GIC_IRQ_TYPE_PARTITION,
-				[1]	= i,
-				[2]	= IRQ_TYPE_NONE,
-			},
-		};
-
-		irq = irq_create_fwspec_mapping(&ppi_fwspec);
-		if (WARN_ON(!irq))
-			continue;
-		desc = partition_create_desc(gic_data.fwnode, parts, nr_parts,
-					     irq, &partition_domain_ops);
-		if (WARN_ON(!desc))
-			continue;
-
-		gic_data.ppi_descs[i] = desc;
-	}
-
 out_put_node:
 	of_node_put(parts_node);
 }
-- 
2.47.3

[PATCH v4 22/26] irqchip/apple-aic: Drop support for custom PMU irq partitions

[Marc Zyngier]

Similarly to what has been done for GICv3, drop the irq partitioning
support from the AIC driver, effectively merging the two per-cpu
interrupts for the PMU.

Reviewed-by: Sven Peter <sven@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/irqchip/irq-apple-aic.c | 28 +++++++---------------------
 1 file changed, 7 insertions(+), 21 deletions(-)

diff --git a/drivers/irqchip/irq-apple-aic.c b/drivers/irqchip/irq-apple-aic.c
index cb8b6f40ce8d3..6305d25b9e77b 100644
--- a/drivers/irqchip/irq-apple-aic.c
+++ b/drivers/irqchip/irq-apple-aic.c
@@ -578,16 +578,9 @@ static void __exception_irq_entry aic_handle_fiq(struct pt_regs *regs)
 	}
 
 	if ((read_sysreg_s(SYS_IMP_APL_PMCR0_EL1) & (PMCR0_IMODE | PMCR0_IACT)) ==
-			(FIELD_PREP(PMCR0_IMODE, PMCR0_IMODE_FIQ) | PMCR0_IACT)) {
-		int irq;
-		if (cpumask_test_cpu(smp_processor_id(),
-				     &aic_irqc->fiq_aff[AIC_CPU_PMU_P]->aff))
-			irq = AIC_CPU_PMU_P;
-		else
-			irq = AIC_CPU_PMU_E;
+			(FIELD_PREP(PMCR0_IMODE, PMCR0_IMODE_FIQ) | PMCR0_IACT))
 		generic_handle_domain_irq(aic_irqc->hw_domain,
-					  AIC_FIQ_HWIRQ(irq));
-	}
+					  AIC_FIQ_HWIRQ(AIC_CPU_PMU_P));
 
 	if (static_branch_likely(&use_fast_ipi) &&
 	    (FIELD_GET(UPMCR0_IMODE, read_sysreg_s(SYS_IMP_APL_UPMCR0_EL1)) == UPMCR0_IMODE_FIQ) &&
@@ -632,18 +625,7 @@ static int aic_irq_domain_map(struct irq_domain *id, unsigned int irq,
 				    handle_fasteoi_irq, NULL, NULL);
 		irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(irq)));
 	} else {
-		int fiq = FIELD_GET(AIC_EVENT_NUM, hw);
-
-		switch (fiq) {
-		case AIC_CPU_PMU_P:
-		case AIC_CPU_PMU_E:
-			irq_set_percpu_devid_partition(irq, &ic->fiq_aff[fiq]->aff);
-			break;
-		default:
-			irq_set_percpu_devid(irq);
-			break;
-		}
-
+		irq_set_percpu_devid(irq);
 		irq_domain_set_info(id, irq, hw, &fiq_chip, id->host_data,
 				    handle_percpu_devid_irq, NULL, NULL);
 	}
@@ -732,6 +714,10 @@ static int aic_irq_domain_translate(struct irq_domain *id,
 				break;
 			}
 		}
+
+		/* Merge the two PMUs on a single interrupt */
+		if (*hwirq == AIC_CPU_PMU_E)
+			*hwirq = AIC_CPU_PMU_P;
 		break;
 	default:
 		return -EINVAL;
-- 
2.47.3

[PATCH v4 23/26] irqchip: Kill irq-partition-percpu

[Marc Zyngier]

This code is now completely unused, and nobody will ever miss it.

Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/irqchip/Kconfig                      |   3 -
 drivers/irqchip/Makefile                     |   1 -
 drivers/irqchip/irq-partition-percpu.c       | 241 -------------------
 include/linux/irqchip/irq-partition-percpu.h |  53 ----
 4 files changed, 298 deletions(-)
 delete mode 100644 drivers/irqchip/irq-partition-percpu.c
 delete mode 100644 include/linux/irqchip/irq-partition-percpu.h

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 648b3618fc784..5dddb4c9442ad 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -450,9 +450,6 @@ config LS_SCFG_MSI
 	depends on PCI_MSI
 	select IRQ_MSI_LIB
 
-config PARTITION_PERCPU
-	bool
-
 config STM32MP_EXTI
 	tristate "STM32MP extended interrupts and event controller"
 	depends on (ARCH_STM32 && !ARM_SINGLE_ARMV7M) || COMPILE_TEST
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 3de083f5484cc..6a229443efe08 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -36,7 +36,6 @@ obj-$(CONFIG_ARM_GIC_V3)		+= irq-gic-v3.o irq-gic-v3-mbi.o irq-gic-common.o
 obj-$(CONFIG_ARM_GIC_ITS_PARENT)	+= irq-gic-its-msi-parent.o
 obj-$(CONFIG_ARM_GIC_V3_ITS)		+= irq-gic-v3-its.o irq-gic-v4.o
 obj-$(CONFIG_ARM_GIC_V3_ITS_FSL_MC)	+= irq-gic-v3-its-fsl-mc-msi.o
-obj-$(CONFIG_PARTITION_PERCPU)		+= irq-partition-percpu.o
 obj-$(CONFIG_ARM_GIC_V5)		+= irq-gic-v5.o irq-gic-v5-irs.o irq-gic-v5-its.o \
 					   irq-gic-v5-iwb.o
 obj-$(CONFIG_HISILICON_IRQ_MBIGEN)	+= irq-mbigen.o
diff --git a/drivers/irqchip/irq-partition-percpu.c b/drivers/irqchip/irq-partition-percpu.c
deleted file mode 100644
index 4441ffe149ea0..0000000000000
--- a/drivers/irqchip/irq-partition-percpu.c
+++ /dev/null
@@ -1,241 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Copyright (C) 2016 ARM Limited, All Rights Reserved.
- * Author: Marc Zyngier <marc.zyngier@arm.com>
- */
-
-#include <linux/bitops.h>
-#include <linux/interrupt.h>
-#include <linux/irqchip.h>
-#include <linux/irqchip/chained_irq.h>
-#include <linux/irqchip/irq-partition-percpu.h>
-#include <linux/irqdomain.h>
-#include <linux/seq_file.h>
-#include <linux/slab.h>
-
-struct partition_desc {
-	int				nr_parts;
-	struct partition_affinity	*parts;
-	struct irq_domain		*domain;
-	struct irq_desc			*chained_desc;
-	unsigned long			*bitmap;
-	struct irq_domain_ops		ops;
-};
-
-static bool partition_check_cpu(struct partition_desc *part,
-				unsigned int cpu, unsigned int hwirq)
-{
-	return cpumask_test_cpu(cpu, &part->parts[hwirq].mask);
-}
-
-static void partition_irq_mask(struct irq_data *d)
-{
-	struct partition_desc *part = irq_data_get_irq_chip_data(d);
-	struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
-	struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
-
-	if (partition_check_cpu(part, smp_processor_id(), d->hwirq) &&
-	    chip->irq_mask)
-		chip->irq_mask(data);
-}
-
-static void partition_irq_unmask(struct irq_data *d)
-{
-	struct partition_desc *part = irq_data_get_irq_chip_data(d);
-	struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
-	struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
-
-	if (partition_check_cpu(part, smp_processor_id(), d->hwirq) &&
-	    chip->irq_unmask)
-		chip->irq_unmask(data);
-}
-
-static int partition_irq_set_irqchip_state(struct irq_data *d,
-					   enum irqchip_irq_state which,
-					   bool val)
-{
-	struct partition_desc *part = irq_data_get_irq_chip_data(d);
-	struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
-	struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
-
-	if (partition_check_cpu(part, smp_processor_id(), d->hwirq) &&
-	    chip->irq_set_irqchip_state)
-		return chip->irq_set_irqchip_state(data, which, val);
-
-	return -EINVAL;
-}
-
-static int partition_irq_get_irqchip_state(struct irq_data *d,
-					   enum irqchip_irq_state which,
-					   bool *val)
-{
-	struct partition_desc *part = irq_data_get_irq_chip_data(d);
-	struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
-	struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
-
-	if (partition_check_cpu(part, smp_processor_id(), d->hwirq) &&
-	    chip->irq_get_irqchip_state)
-		return chip->irq_get_irqchip_state(data, which, val);
-
-	return -EINVAL;
-}
-
-static int partition_irq_set_type(struct irq_data *d, unsigned int type)
-{
-	struct partition_desc *part = irq_data_get_irq_chip_data(d);
-	struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
-	struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
-
-	if (chip->irq_set_type)
-		return chip->irq_set_type(data, type);
-
-	return -EINVAL;
-}
-
-static void partition_irq_print_chip(struct irq_data *d, struct seq_file *p)
-{
-	struct partition_desc *part = irq_data_get_irq_chip_data(d);
-	struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
-	struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
-
-	seq_printf(p, "%5s-%lu", chip->name, data->hwirq);
-}
-
-static struct irq_chip partition_irq_chip = {
-	.irq_mask		= partition_irq_mask,
-	.irq_unmask		= partition_irq_unmask,
-	.irq_set_type		= partition_irq_set_type,
-	.irq_get_irqchip_state	= partition_irq_get_irqchip_state,
-	.irq_set_irqchip_state	= partition_irq_set_irqchip_state,
-	.irq_print_chip		= partition_irq_print_chip,
-};
-
-static void partition_handle_irq(struct irq_desc *desc)
-{
-	struct partition_desc *part = irq_desc_get_handler_data(desc);
-	struct irq_chip *chip = irq_desc_get_chip(desc);
-	int cpu = smp_processor_id();
-	int hwirq;
-
-	chained_irq_enter(chip, desc);
-
-	for_each_set_bit(hwirq, part->bitmap, part->nr_parts) {
-		if (partition_check_cpu(part, cpu, hwirq))
-			break;
-	}
-
-	if (unlikely(hwirq == part->nr_parts))
-		handle_bad_irq(desc);
-	else
-		generic_handle_domain_irq(part->domain, hwirq);
-
-	chained_irq_exit(chip, desc);
-}
-
-static int partition_domain_alloc(struct irq_domain *domain, unsigned int virq,
-				  unsigned int nr_irqs, void *arg)
-{
-	int ret;
-	irq_hw_number_t hwirq;
-	unsigned int type;
-	struct irq_fwspec *fwspec = arg;
-	struct partition_desc *part;
-
-	BUG_ON(nr_irqs != 1);
-	ret = domain->ops->translate(domain, fwspec, &hwirq, &type);
-	if (ret)
-		return ret;
-
-	part = domain->host_data;
-
-	set_bit(hwirq, part->bitmap);
-	irq_set_chained_handler_and_data(irq_desc_get_irq(part->chained_desc),
-					 partition_handle_irq, part);
-	irq_set_percpu_devid_partition(virq, &part->parts[hwirq].mask);
-	irq_domain_set_info(domain, virq, hwirq, &partition_irq_chip, part,
-			    handle_percpu_devid_irq, NULL, NULL);
-	irq_set_status_flags(virq, IRQ_NOAUTOEN);
-
-	return 0;
-}
-
-static void partition_domain_free(struct irq_domain *domain, unsigned int virq,
-				  unsigned int nr_irqs)
-{
-	struct irq_data *d;
-
-	BUG_ON(nr_irqs != 1);
-
-	d = irq_domain_get_irq_data(domain, virq);
-	irq_set_handler(virq, NULL);
-	irq_domain_reset_irq_data(d);
-}
-
-int partition_translate_id(struct partition_desc *desc, void *partition_id)
-{
-	struct partition_affinity *part = NULL;
-	int i;
-
-	for (i = 0; i < desc->nr_parts; i++) {
-		if (desc->parts[i].partition_id == partition_id) {
-			part = &desc->parts[i];
-			break;
-		}
-	}
-
-	if (WARN_ON(!part)) {
-		pr_err("Failed to find partition\n");
-		return -EINVAL;
-	}
-
-	return i;
-}
-
-struct partition_desc *partition_create_desc(struct fwnode_handle *fwnode,
-					     struct partition_affinity *parts,
-					     int nr_parts,
-					     int chained_irq,
-					     const struct irq_domain_ops *ops)
-{
-	struct partition_desc *desc;
-	struct irq_domain *d;
-
-	BUG_ON(!ops->select || !ops->translate);
-
-	desc = kzalloc(sizeof(*desc), GFP_KERNEL);
-	if (!desc)
-		return NULL;
-
-	desc->ops = *ops;
-	desc->ops.free = partition_domain_free;
-	desc->ops.alloc = partition_domain_alloc;
-
-	d = irq_domain_create_linear(fwnode, nr_parts, &desc->ops, desc);
-	if (!d)
-		goto out;
-	desc->domain = d;
-
-	desc->bitmap = bitmap_zalloc(nr_parts, GFP_KERNEL);
-	if (WARN_ON(!desc->bitmap))
-		goto out;
-
-	desc->chained_desc = irq_to_desc(chained_irq);
-	desc->nr_parts = nr_parts;
-	desc->parts = parts;
-
-	return desc;
-out:
-	if (d)
-		irq_domain_remove(d);
-	kfree(desc);
-
-	return NULL;
-}
-
-struct irq_domain *partition_get_domain(struct partition_desc *dsc)
-{
-	if (dsc)
-		return dsc->domain;
-
-	return NULL;
-}
diff --git a/include/linux/irqchip/irq-partition-percpu.h b/include/linux/irqchip/irq-partition-percpu.h
deleted file mode 100644
index b35ee22c278f8..0000000000000
--- a/include/linux/irqchip/irq-partition-percpu.h
+++ /dev/null
@@ -1,53 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copyright (C) 2016 ARM Limited, All Rights Reserved.
- * Author: Marc Zyngier <marc.zyngier@arm.com>
- */
-
-#ifndef __LINUX_IRQCHIP_IRQ_PARTITION_PERCPU_H
-#define __LINUX_IRQCHIP_IRQ_PARTITION_PERCPU_H
-
-#include <linux/fwnode.h>
-#include <linux/cpumask_types.h>
-#include <linux/irqdomain.h>
-
-struct partition_affinity {
-	cpumask_t			mask;
-	void				*partition_id;
-};
-
-struct partition_desc;
-
-#ifdef CONFIG_PARTITION_PERCPU
-int partition_translate_id(struct partition_desc *desc, void *partition_id);
-struct partition_desc *partition_create_desc(struct fwnode_handle *fwnode,
-					     struct partition_affinity *parts,
-					     int nr_parts,
-					     int chained_irq,
-					     const struct irq_domain_ops *ops);
-struct irq_domain *partition_get_domain(struct partition_desc *dsc);
-#else
-static inline int partition_translate_id(struct partition_desc *desc,
-					 void *partition_id)
-{
-	return -EINVAL;
-}
-
-static inline
-struct partition_desc *partition_create_desc(struct fwnode_handle *fwnode,
-					     struct partition_affinity *parts,
-					     int nr_parts,
-					     int chained_irq,
-					     const struct irq_domain_ops *ops)
-{
-	return NULL;
-}
-
-static inline
-struct irq_domain *partition_get_domain(struct partition_desc *dsc)
-{
-	return NULL;
-}
-#endif
-
-#endif /* __LINUX_IRQCHIP_IRQ_PARTITION_PERCPU_H */
-- 
2.47.3

[PATCH v4 24/26] genirq: Kill irq_{g,s}et_percpu_devid_partition()

[Marc Zyngier]

These two helpers do not have any user anymore, and can be removed,
together with the affinity field kept in the irqdesc structure.

Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 include/linux/irq.h     |  4 ----
 include/linux/irqdesc.h |  1 -
 kernel/irq/irqdesc.c    | 24 +-----------------------
 3 files changed, 1 insertion(+), 28 deletions(-)

diff --git a/include/linux/irq.h b/include/linux/irq.h
index b728c18f6ded7..4a9f1d7b08c39 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -718,10 +718,6 @@ static inline void irq_set_chip_and_handler(unsigned int irq,
 }
 
 extern int irq_set_percpu_devid(unsigned int irq);
-extern int irq_set_percpu_devid_partition(unsigned int irq,
-					  const struct cpumask *affinity);
-extern int irq_get_percpu_devid_partition(unsigned int irq,
-					  struct cpumask *affinity);
 
 extern void
 __irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h
index fd091c35d5721..37e0b5b5600a4 100644
--- a/include/linux/irqdesc.h
+++ b/include/linux/irqdesc.h
@@ -82,7 +82,6 @@ struct irq_desc {
 	int			threads_handled_last;
 	raw_spinlock_t		lock;
 	struct cpumask		*percpu_enabled;
-	const struct cpumask	*percpu_affinity;
 #ifdef CONFIG_SMP
 	const struct cpumask	*affinity_hint;
 	struct irq_affinity_notify *affinity_notify;
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index db714d3014b5f..6acf268f005bc 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -879,8 +879,7 @@ void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
 		chip_bus_sync_unlock(desc);
 }
 
-int irq_set_percpu_devid_partition(unsigned int irq,
-				   const struct cpumask *affinity)
+int irq_set_percpu_devid(unsigned int irq)
 {
 	struct irq_desc *desc = irq_to_desc(irq);
 
@@ -892,31 +891,10 @@ int irq_set_percpu_devid_partition(unsigned int irq,
 	if (!desc->percpu_enabled)
 		return -ENOMEM;
 
-	desc->percpu_affinity = affinity ? : cpu_possible_mask;
-
 	irq_set_percpu_devid_flags(irq);
 	return 0;
 }
 
-int irq_set_percpu_devid(unsigned int irq)
-{
-	return irq_set_percpu_devid_partition(irq, NULL);
-}
-
-int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity)
-{
-	struct irq_desc *desc = irq_to_desc(irq);
-
-	if (!desc || !desc->percpu_enabled)
-		return -EINVAL;
-
-	if (affinity)
-		cpumask_copy(affinity, desc->percpu_affinity);
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(irq_get_percpu_devid_partition);
-
 void kstat_incr_irq_this_cpu(unsigned int irq)
 {
 	kstat_incr_irqs_this_cpu(irq_to_desc(irq));
-- 
2.47.3

[PATCH v4 25/26] irqdomain: Kill of_node_to_fwnode() helper

[Marc Zyngier]

There is no in-tree users of this helper since b13b41cc3dc18 ("misc:
ti_fpc202: Switch to of_fwnode_handle()"), and is replaced with
of_fwnode_handle().

Get rid of it.

Suggested-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 include/linux/irqdomain.h | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
index 9d6a5e99394fa..5907baf6099d9 100644
--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -730,12 +730,6 @@ static inline void msi_device_domain_free_wired(struct irq_domain *domain, unsig
 }
 #endif
 
-/* Deprecated functions. Will be removed in the merge window */
-static inline struct fwnode_handle *of_node_to_fwnode(struct device_node *node)
-{
-	return node ? &node->fwnode : NULL;
-}
-
 static inline struct irq_domain *irq_domain_add_tree(struct device_node *of_node,
 						     const struct irq_domain_ops *ops,
 						     void *host_data)
-- 
2.47.3

[PATCH v4 26/26] perf: arm_pmu: Kill last use of per-CPU cpu_armpmu pointer

[Marc Zyngier]

Having removed the use of the cpu_armpmu per-CPU variable from the
interrupt handling, the only user left is the BRBE scheduler hook.

It is easy to drop the use of this variable by following the pointer
to the generic PMU structure, and get the arm_pmu structure from there.

Perform the conversion and kill cpu_armpmu altogether.

Suggested-by: Will Deacon <will@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/perf/arm_pmu.c       | 5 -----
 drivers/perf/arm_pmuv3.c     | 2 +-
 include/linux/perf/arm_pmu.h | 2 --
 3 files changed, 1 insertion(+), 8 deletions(-)

diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
index 959ceb3d1f556..f7abd13339630 100644
--- a/drivers/perf/arm_pmu.c
+++ b/drivers/perf/arm_pmu.c
@@ -104,7 +104,6 @@ static const struct pmu_irq_ops percpu_pmunmi_ops = {
 	.free_pmuirq = armpmu_free_percpu_pmunmi
 };
 
-DEFINE_PER_CPU(struct arm_pmu *, cpu_armpmu);
 static DEFINE_PER_CPU(int, cpu_irq);
 static DEFINE_PER_CPU(const struct pmu_irq_ops *, cpu_irq_ops);
 
@@ -725,8 +724,6 @@ static int arm_perf_starting_cpu(unsigned int cpu, struct hlist_node *node)
 	if (pmu->reset)
 		pmu->reset(pmu);
 
-	per_cpu(cpu_armpmu, cpu) = pmu;
-
 	irq = armpmu_get_cpu_irq(pmu, cpu);
 	if (irq)
 		per_cpu(cpu_irq_ops, cpu)->enable_pmuirq(irq);
@@ -746,8 +743,6 @@ static int arm_perf_teardown_cpu(unsigned int cpu, struct hlist_node *node)
 	if (irq)
 		per_cpu(cpu_irq_ops, cpu)->disable_pmuirq(irq);
 
-	per_cpu(cpu_armpmu, cpu) = NULL;
-
 	return 0;
 }
 
diff --git a/drivers/perf/arm_pmuv3.c b/drivers/perf/arm_pmuv3.c
index 69c5cc8f56067..ca8d706d40221 100644
--- a/drivers/perf/arm_pmuv3.c
+++ b/drivers/perf/arm_pmuv3.c
@@ -1064,7 +1064,7 @@ static int armv8pmu_user_event_idx(struct perf_event *event)
 static void armv8pmu_sched_task(struct perf_event_pmu_context *pmu_ctx,
 				struct task_struct *task, bool sched_in)
 {
-	struct arm_pmu *armpmu = *this_cpu_ptr(&cpu_armpmu);
+	struct arm_pmu *armpmu = to_arm_pmu(pmu_ctx->pmu);
 	struct pmu_hw_events *hw_events = this_cpu_ptr(armpmu->hw_events);
 
 	if (!hw_events->branch_users)
diff --git a/include/linux/perf/arm_pmu.h b/include/linux/perf/arm_pmu.h
index 6690bd77aa4ee..bab26a7d79f4c 100644
--- a/include/linux/perf/arm_pmu.h
+++ b/include/linux/perf/arm_pmu.h
@@ -132,8 +132,6 @@ struct arm_pmu {
 
 #define to_arm_pmu(p) (container_of(p, struct arm_pmu, pmu))
 
-DECLARE_PER_CPU(struct arm_pmu *, cpu_armpmu);
-
 u64 armpmu_event_update(struct perf_event *event);
 
 int armpmu_event_set_period(struct perf_event *event);
-- 
2.47.3

Re: [PATCH v4 05/26] irqchip/gic-v3: Add FW info retrieval support

[Jonathan Cameron]

On Mon, 20 Oct 2025 13:29:22 +0100
Marc Zyngier <maz@kernel.org> wrote:

> Plug the new .get_fwspec_info() callback into the GICv3 core driver,
> using some of the existing PPI affinity handling infrastructure.
> 
> Tested-by: Will Deacon <will@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

Re: [PATCH v4 07/26] coresight: trbe: Convert to new IRQ affinity retrieval API

[Jonathan Cameron]

On Mon, 20 Oct 2025 13:29:24 +0100
Marc Zyngier <maz@kernel.org> wrote:

> Now that the relevant interrupt controllers are equipped with
> a callback returning the affinity of per-CPU interrupts, switch
> the TRBE driver over to this new method.
> 
> Acked-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> Tested-by: Will Deacon <will@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

Re: [PATCH v4 08/26] perf: arm_pmu: Convert to new IRQ affinity retrieval API

[Jonathan Cameron]

On Mon, 20 Oct 2025 13:29:25 +0100
Marc Zyngier <maz@kernel.org> wrote:

> Now that the relevant interrupt controllers are equipped with
> a callback returning the affinity of per-CPU interrupts, switch
> the OF side of the ARM PMU driver over to this new method.
> 
> Reviewed-by: Jinjie Ruan <ruanjinjie@huawei.com>
> Tested-by: Will Deacon <will@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

Re: [PATCH v4 09/26] perf: arm_spe_pmu: Convert to new IRQ affinity retrieval API

[Jonathan Cameron]

On Mon, 20 Oct 2025 13:29:26 +0100
Marc Zyngier <maz@kernel.org> wrote:

> Now that the relevant interrupt controllers are equipped with
> a callback returning the affinity of per-CPU interrupts, switch
> the ARM SPE driver over to this new method.
> 
> Reviewed-by: Jinjie Ruan <ruanjinjie@huawei.com>
> Tested-by: Will Deacon <will@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

Re: [PATCH v4 10/26] irqchip/gic-v3: Switch high priority PPIs over to handle_percpu_devid_irq()

[Jonathan Cameron]

On Mon, 20 Oct 2025 13:29:27 +0100
Marc Zyngier <maz@kernel.org> wrote:

> It so appears that handle_percpu_devid_irq() is extremely similar to
> handle_percpu_devid_fasteoi_nmi(), and that the differences do no
> justify the horrid machinery we have in the GICv3 driver to handle
> the flow handler switch.
> 
> Let's stick with the standard flow handler, even for NMIs.
> 
> Suggested-by: Will Deacon <will@kernel.org>
> Tested-by: Will Deacon <will@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
LGTM and who doesn't like those diff stats ;)
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
> ---
>  drivers/irqchip/irq-gic-v3.c | 54 ++----------------------------------
>  1 file changed, 2 insertions(+), 52 deletions(-)

Re: [PATCH v4 11/26] genirq: Kill handle_percpu_devid_fasteoi_nmi()

[Jonathan Cameron]

On Mon, 20 Oct 2025 13:29:28 +0100
Marc Zyngier <maz@kernel.org> wrote:

> There is no in-tree user of this flow handler anymore, so simply
> remove it.
> 
> Suggested-by: Will Deacon <will@kernel.org>
> Tested-by: Will Deacon <will@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

Re: [PATCH v4 12/26] genirq: Merge irqaction::{dev_id,percpu_dev_id}

[Jonathan Cameron]

On Mon, 20 Oct 2025 13:29:29 +0100
Marc Zyngier <maz@kernel.org> wrote:

> When irqaction::percpu_dev_id was introduced, it was hoped that it
> could be part of an anonymous union with dev_id, as the two fields
> are mutually exclusive.
> 
> However, toolchains used at the time were often showing terrible
> support for anonymous unions, breaking the build on a number of
> architectures. It was therefore decided to keep the two fields separate
> and address this down the line.
> 
> 14 years later, the compiler dark age is over, and there is universal
> support for anonymous unions. Let's get a whole pointer back that can
> immediately be spent on something else.
> 
> Tested-by: Will Deacon <will@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
I'm glad I either never saw that anon union problem or have blanked it from
my mind.

Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

Re: [PATCH v4 14/26] genirq: Add affinity to percpu_devid interrupt requests

[Jonathan Cameron]

On Mon, 20 Oct 2025 13:29:31 +0100
Marc Zyngier <maz@kernel.org> wrote:

> Add an affinity field to both the irqaction structure and the interrupt
> request primitives. Nothing is making use of it yet, and the only value
> used it NULL, which is used as a shorthand for cpu_possible_mask.

used is NULL

> 
> This will shortly get used with actual affinities.
> 
> Tested-by: Will Deacon <will@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>

With trivial bit of documentation added
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

> ---
>  include/linux/interrupt.h |  5 +++--
>  kernel/irq/manage.c       | 14 ++++++++++----
>  2 files changed, 13 insertions(+), 6 deletions(-)
> 
> diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
> index 0ec1a71ab4e84..52147d5f432b3 100644
> --- a/include/linux/interrupt.h
> +++ b/include/linux/interrupt.h
> @@ -125,6 +125,7 @@ struct irqaction {
>  		void		*dev_id;
>  		void __percpu	*percpu_dev_id;
>  	};
> +	const struct cpumask	*affinity;

This structure has kernel-doc that needs an update.

>  	struct irqaction	*next;
>  	irq_handler_t		thread_fn;
>  	struct task_struct	*thread;

Re: [PATCH v4 15/26] genirq: Update request_percpu_nmi() to take an affinity

[Jonathan Cameron]

On Mon, 20 Oct 2025 13:29:32 +0100
Marc Zyngier <maz@kernel.org> wrote:

> Continue spreading the notion of affinity to the percpu interrupt
> request code by updating the call sites that use request_percpu_nmi()
> (all two of them) to take an affinity pointer. This pointer is
> firmly NULL for now.
> 
> Tested-by: Will Deacon <will@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>

Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

Re: [PATCH v4 16/26] genirq: Allow per-cpu interrupt sharing for non-overlapping affinities

[Jonathan Cameron]

On Mon, 20 Oct 2025 13:29:33 +0100
Marc Zyngier <maz@kernel.org> wrote:

> Interrupt sharing for percpu-devid interrupts is forbidden, and
> for good reasons. These are interrupts generated *from* a CPU and
> handled by itself (timer, for example). Nobody in their right mind
> would put two devices on the same pin (and if they have, they get to
> keep the pieces...).
> 
> But this also prevents more benign cases, where devices are connected
> to groups of CPUs, and for which the affinities are not overlapping.
> Effectively, the only thing they share is the interrupt number, and
> nothing else.
> 
> Let's tweak the definition of IRQF_SHARED applied to percpu_devid
> interrupts to allow this particular case. This results in extra
> validation at the point of the interrupt being setup and freed,
> as well as a tiny bit of extra complexity for interrupts at handling
> time (to pick the correct irqaction).
> 
> Tested-by: Will Deacon <will@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

Re: [PATCH v4 17/26] genirq: Add request_percpu_irq_affinity() helper

[Jonathan Cameron]

On Mon, 20 Oct 2025 13:29:34 +0100
Marc Zyngier <maz@kernel.org> wrote:

> While it would be nice to simply make request_percpu_irq() take
> an affinity mask, the churn is likely to be on the irritating side
> given that most drivers do not give a damn about affinities.

Only 37 instances. I'd have been tempted to do it anyway :)

> 
> So take the more innocuous path to provide a helper that parallels
> request_percpu_irq(), with an affinity as a bonus argument.
> 
> Yes, request_percpu_irq_affinity() is a bit of a mouthful.
> 
> Tested-by: Will Deacon <will@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

Re: [PATCH v4 18/26] perf: arm_pmu: Request specific affinities for percpu NMI/IRQ

[Jonathan Cameron]

On Mon, 20 Oct 2025 13:29:35 +0100
Marc Zyngier <maz@kernel.org> wrote:

> From: Will Deacon <will@kernel.org>
> 
> Let the PMU driver request both NMI and normal IRQs with an affinity
> mask matching the PMU affinity.
> 
> Signed-off-by: Will Deacon <will@kernel.org>
> Tested-by: Will Deacon <will@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>

Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

Re: [PATCH v4 19/26] perf: arm_spe_pmu: Request specific affinities for percpu IRQ

[Jonathan Cameron]

On Mon, 20 Oct 2025 13:29:36 +0100
Marc Zyngier <maz@kernel.org> wrote:

> Let the SPE driver request IRQs with an affinity mask matching
> the SPE implementation affinity.
> 
> Tested-by: Will Deacon <will@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

> ---
>  drivers/perf/arm_spe_pmu.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/perf/arm_spe_pmu.c b/drivers/perf/arm_spe_pmu.c
> index 1460b02d20e8b..87908f0712c0c 100644
> --- a/drivers/perf/arm_spe_pmu.c
> +++ b/drivers/perf/arm_spe_pmu.c
> @@ -1259,8 +1259,8 @@ static int arm_spe_pmu_dev_init(struct arm_spe_pmu *spe_pmu)
>  		return -ENXIO;
>  
>  	/* Request our PPIs (note that the IRQ is still disabled) */
> -	ret = request_percpu_irq(spe_pmu->irq, arm_spe_pmu_irq_handler, DRVNAME,
> -				 spe_pmu->handle);
> +	ret = request_percpu_irq_affinity(spe_pmu->irq, arm_spe_pmu_irq_handler,
> +					  DRVNAME, mask, spe_pmu->handle);
>  	if (ret)
>  		return ret;
>  

Re: [PATCH v4 20/26] coresight: trbe: Request specific affinities for percpu IRQ

[Jonathan Cameron]

On Mon, 20 Oct 2025 13:29:37 +0100
Marc Zyngier <maz@kernel.org> wrote:

> Let the TRBE driver request IRQs with an affinity mask matching
> the TRBE implementation affinity.
> 
> Acked-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> Tested-by: Will Deacon <will@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
FWIW given how simple this is.
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

Re: [PATCH v4 25/26] irqdomain: Kill of_node_to_fwnode() helper

[Jonathan Cameron]

On Mon, 20 Oct 2025 13:29:42 +0100
Marc Zyngier <maz@kernel.org> wrote:

> There is no in-tree users of this helper since b13b41cc3dc18 ("misc:
> ti_fpc202: Switch to of_fwnode_handle()"), and is replaced with
> of_fwnode_handle().
> 
> Get rid of it.
> 
> Suggested-by: Jonathan Cameron <jonathan.cameron@huawei.com>
> Tested-by: Will Deacon <will@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>

Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
I didn't bother checking all the other removal patches but didn't see
anything wrong with them!  Ripping code out is (usually) uncontroversial.


> ---
>  include/linux/irqdomain.h | 6 ------
>  1 file changed, 6 deletions(-)
> 
> diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
> index 9d6a5e99394fa..5907baf6099d9 100644
> --- a/include/linux/irqdomain.h
> +++ b/include/linux/irqdomain.h
> @@ -730,12 +730,6 @@ static inline void msi_device_domain_free_wired(struct irq_domain *domain, unsig
>  }
>  #endif
>  
> -/* Deprecated functions. Will be removed in the merge window */
> -static inline struct fwnode_handle *of_node_to_fwnode(struct device_node *node)
> -{
> -	return node ? &node->fwnode : NULL;
> -}
> -
>  static inline struct irq_domain *irq_domain_add_tree(struct device_node *of_node,
>  						     const struct irq_domain_ops *ops,
>  						     void *host_data)

Re: [PATCH v4 14/26] genirq: Add affinity to percpu_devid interrupt requests

[Marc Zyngier]

On Wed, 12 Nov 2025 18:13:18 +0000,
Jonathan Cameron <jonathan.cameron@huawei.com> wrote:
> 
> On Mon, 20 Oct 2025 13:29:31 +0100
> Marc Zyngier <maz@kernel.org> wrote:
> 
> > Add an affinity field to both the irqaction structure and the interrupt
> > request primitives. Nothing is making use of it yet, and the only value
> > used it NULL, which is used as a shorthand for cpu_possible_mask.
> 
> used is NULL
> 
> > 
> > This will shortly get used with actual affinities.
> > 
> > Tested-by: Will Deacon <will@kernel.org>
> > Signed-off-by: Marc Zyngier <maz@kernel.org>
> 
> With trivial bit of documentation added
> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
> 
> > ---
> >  include/linux/interrupt.h |  5 +++--
> >  kernel/irq/manage.c       | 14 ++++++++++----
> >  2 files changed, 13 insertions(+), 6 deletions(-)
> > 
> > diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
> > index 0ec1a71ab4e84..52147d5f432b3 100644
> > --- a/include/linux/interrupt.h
> > +++ b/include/linux/interrupt.h
> > @@ -125,6 +125,7 @@ struct irqaction {
> >  		void		*dev_id;
> >  		void __percpu	*percpu_dev_id;
> >  	};
> > +	const struct cpumask	*affinity;
> 
> This structure has kernel-doc that needs an update.
> 
> >  	struct irqaction	*next;
> >  	irq_handler_t		thread_fn;
> >  	struct task_struct	*thread;

See 68c4c159a0db4 ("genirq: Fix percpu_devid irq affinity
documentation") in -next for the merged fix.

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.

Re: [PATCH v4 17/26] genirq: Add request_percpu_irq_affinity() helper

[Marc Zyngier]

On Wed, 12 Nov 2025 18:27:35 +0000,
Jonathan Cameron <jonathan.cameron@huawei.com> wrote:
> 
> On Mon, 20 Oct 2025 13:29:34 +0100
> Marc Zyngier <maz@kernel.org> wrote:
> 
> > While it would be nice to simply make request_percpu_irq() take
> > an affinity mask, the churn is likely to be on the irritating side
> > given that most drivers do not give a damn about affinities.
> 
> Only 37 instances. I'd have been tempted to do it anyway :)

I'm leaving this as an exercise for people who enjoy cross-subsystem
patch series!

> 
> > 
> > So take the more innocuous path to provide a helper that parallels
> > request_percpu_irq(), with an affinity as a bonus argument.
> > 
> > Yes, request_percpu_irq_affinity() is a bit of a mouthful.
> > 
> > Tested-by: Will Deacon <will@kernel.org>
> > Signed-off-by: Marc Zyngier <maz@kernel.org>
> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.

Re: [PATCH v4 16/26] genirq: Allow per-cpu interrupt sharing for non-overlapping affinities

[Daniel Thompson]

On Mon, Oct 20, 2025 at 01:29:33PM +0100, Marc Zyngier wrote:
> Interrupt sharing for percpu-devid interrupts is forbidden, and
> for good reasons. These are interrupts generated *from* a CPU and
> handled by itself (timer, for example). Nobody in their right mind
> would put two devices on the same pin (and if they have, they get to
> keep the pieces...).
>
> But this also prevents more benign cases, where devices are connected
> to groups of CPUs, and for which the affinities are not overlapping.
> Effectively, the only thing they share is the interrupt number, and
> nothing else.
>
> Let's tweak the definition of IRQF_SHARED applied to percpu_devid
> interrupts to allow this particular case. This results in extra
> validation at the point of the interrupt being setup and freed,
> as well as a tiny bit of extra complexity for interrupts at handling
> time (to pick the correct irqaction).
>
> Tested-by: Will Deacon <will@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>

I picked up this patch via linux-next and it appears be causing boot
regressions on MIPS/qemu. This patch was identified with a bisect and
a git revert of this patch from the linux-next tip resolves the problem
(specifically, next-20251204 with git revert bdf4e2ac295f).

I'm running the code as part of the kgdb test suite but the system
doesn't survive long enough for kgdb to be involved. In fact I was able
to reduce things to the following reproduction with all the kgdb pieces
removed:

    make malta_kvm_defconfig generic/64r6.config
    ../scripts/config \
        --enable WERROR --enable CPU_MIPS64_R6 --enable MIPS_CPS \
	--enable BLK_DEV_INITRD --set-val FRAME_WARN 2048
    make olddefconfig
    make -j$(nproc) all
    qemu-system-mips64el -cpu I6400 -M malta -m 1G -smp 2 \
        -kernel vmlinux -nographic \
	-append " console=ttyS0,115200 clk_ignore_unused"

The stack dumps continually so I have to abridge the logs but the logs
to second stack trace are:

~~~
Linux version 6.18.0-next-20251204 (drt@wychelm) (mips64el-linux-gcc.br_real (Buildroot 2025.02.8) 14.3.0, GNU ld (GNU Binutils) 2.44) #20 SMP Thu Dec  4 10:37:28 GMT 2025
earlycon: uart8250 at I/O port 0x3f8 (options '38400n8')
printk: legacy bootconsole [uart8250] enabled
CPU0 revision is: 0001a900 (MIPS I6400)
FPU revision is: 20f30300
MSA revision is: 00000300
MIPS: machine is mti,malta
Software DMA cache coherency enabled
Initial ramdisk at: 0x900000000fc40000 (3818338 bytes)
OF: reserved mem: Reserved memory: No reserved-memory node in the DT
VP topology {2} total 2
Primary instruction cache 64kB, VIPT, 4-way, linesize 64 bytes.
Primary data cache 64kB, 4-way, PIPT, no aliases, linesize 64 bytes
Zone ranges:
  DMA      [mem 0x0000000000000000-0x0000000000ffffff]
  DMA32    [mem 0x0000000001000000-0x00000000ffffffff]
  Normal   empty
Movable zone start for each node
Early memory node ranges
  node   0: [mem 0x0000000000000000-0x000000000fffffff]
  node   0: [mem 0x0000000090000000-0x00000000bfffffff]
Initmem setup node 0 [mem 0x0000000000000000-0x00000000bfffffff]
On node 0, zone DMA32: 131072 pages in unavailable ranges
random: crng init done
percpu: Embedded 7 pages/cpu s69728 r8192 d36768 u114688
Kernel command line: rd_start=0xffffffff8fc40000 rd_size=3818338  console=ttyS0,115200 kgdboc=ttyS0 clk_ignore_unused
Unknown kernel command line parameters "kgdboc=ttyS0", will be passed to user space.
printk: log buffer data + meta data: 32768 + 114688 = 147456 bytes
Dentry cache hash table entries: 131072 (order: 6, 1048576 bytes, linear)
Inode-cache hash table entries: 65536 (order: 5, 524288 bytes, linear)
Cache parity protection disabled
MAAR configuration:
  [0]: 0x0000000000000000-0x000000000fffffff speculate
  [1]: 0x0000000090000000-0x00000000bfffffff speculate
  [2]: disabled
  [3]: disabled
  [4]: disabled
  [5]: disabled
  [6]: disabled
  [7]: disabled
Built 1 zonelists, mobility grouping on.  Total pages: 65536
mem auto-init: stack:all(zero), heap alloc:off, heap free:off
SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=2, Nodes=1
rcu: Hierarchical RCU implementation.
rcu: 	RCU event tracing is enabled.
	Tracing variant of Tasks RCU enabled.
rcu: RCU calculated value of scheduler-enlistment delay is 10 jiffies.
RCU Tasks Trace: Setting shift to 1 and lim to 1 rcu_task_cb_adjust=1 rcu_task_cpu_ids=2.
NR_IRQS: 256
rcu: srcu_init: Setting srcu_struct sizes based on contention.
CPU frequency 320.00 MHz
GIC frequency 100.00 MHz
clocksource: GIC: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19113045595 ns
sched_clock: 32 bits at 100MHz, resolution 10ns, wraps every 21475332090ns
clocksource: MIPS: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 11945377117 ns
Console: colour dummy device 80x25
Calibrating delay loop...
CPU 0 Unable to handle kernel paging request at virtual address 0000000000000000, epc == ffffffff801c2398, ra == ffffffff801bab00
Oops[#1]:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.18.0-next-20251204 #20 NONE
Hardware name: mti,malta
$ 0   : 0000000000000000 0000000000000001 0000000000000000 0000000000000000
$ 4   : 0000000000000001 a8000000020e8008 0000000000000000 ffffffff80c23b80
$ 8   : 0000000000000004 0000000000000000 0000000000000000 000000000000002f
$12   : a8000000020f4000 0000000000003ff0 0000000000003000 0000000000000003
$16   : ffffffff80d095c0 ffffffff80ceb410 0000000000000019 ffffffff80c378c0
$20   : ffffffff80c4bec8 0000000000000000 ffffffff80e00000 ffffffff80de0000
$24   : 0000000000000000 0000000000000010
$28   : ffffffff80c20000 a8000000020f7ec0 a800000000e12fcd ffffffff801bab00
epc   : ffffffff801c2398 handle_percpu_devid_irq+0xb8/0x250
ra    : ffffffff801bab00 handle_irq_desc+0x48/0x88
Status: 1400a4e2	KX SX UX KERNEL EXL
Cause : 00800408 (ExcCode 02)
BadVA : 0000000000000000
PrId  : 0001a900 (MIPS I6400)
Modules linked in:
Process swapper/0 (pid: 0, threadinfo=(____ptrval____), task=(____ptrval____), tls=0000000000000000)
Stack : ffffffff80c35a2c 0000000000000002 ffffffff80e00000 0fffffffffffffff
        ffffffff80c50000 0000000000000001 0000000000000003 ffffffff801bab00
        0000000000000000 ffffffff805d82a8 0000000000000000 0000000000000008
        0000000000000000 0000000000000000 0000000000000000 5189d95a7a4f4800
        a800000002014300 0000000000000002 0000000000000001 000000000000001f
        ffffffff80e00000 0000000000000004 0000000000000000 ffffffff801bab00
        0000000000000000 ffffffff809ec128 0000000000000001 fffffffffffffffb
        0000000000000001 ffffffff805d7ebc 0000000000000000 0000000000000000
        ffffffff80c23c80 ffffffff80c50000 ffffffff80de0000 ffffffff80db0000
        0000000000000000 ffffffff80112f10 ffffffff80c23c80 0000000000000000
Call Trace:
[<ffffffff801c2398>] handle_percpu_devid_irq+0xb8/0x250
[<ffffffff801bab00>] handle_irq_desc+0x48/0x88
[<ffffffff805d82a8>] gic_irq_dispatch+0xc0/0x288
[<ffffffff801bab00>] handle_irq_desc+0x48/0x88
[<ffffffff809ec128>] do_domain_IRQ+0x28/0x40
[<ffffffff805d7ebc>] plat_irq_dispatch+0x64/0xe8
[<ffffffff80112f10>] handle_int+0x134/0x140
[<ffffffff80110dc8>] calibrate_delay+0x158/0x290
[<ffffffff80d58e48>] start_kernel+0x754/0x7a4

Code: da000048  de020010  0043102d <dc420000> 00c21016  30420001  d85ffff8  00000000  00000000

CPU 0 Unable to handle kernel paging request at virtual address 0000000000000000, epc == ffffffff801c2398, ra == ffffffff801bab00
Oops[#2]:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G      D             6.18.0-next-20251204 #20 NONE
Tainted: [D]=DIE
Hardware name: mti,malta
$ 0   : 0000000000000000 0000000000000001 0000000000000000 0000000000000000
$ 4   : 0000000000000002 a8000000020e8008 0000000000000000 a8000000020f7ae0
$ 8   : 0000000000000004 0000000000000000 0000000000000000 0000000000000000
$12   : a8000000020f4000 a8000000020f4000 0000000000003000 0000000000000000
$16   : ffffffff80d095c0 ffffffff80ceb410 0000000000000019 ffffffff80c378c0
$20   : ffffffff80c4bec8 0000000000000000 ffffffff80e00000 0000000000000001
$24   : 0000000000000000 ffffffffffffffff
$28   : ffffffff80c20000 a8000000020f7ab0 a800000000e12fcd ffffffff801bab00
epc   : ffffffff801c2398 handle_percpu_devid_irq+0xb8/0x250
ra    : ffffffff801bab00 handle_irq_desc+0x48/0x88
Status: 1400a4e2	KX SX UX KERNEL EXL
Cause : 00800408 (ExcCode 02)
BadVA : 0000000000000000
PrId  : 0001a900 (MIPS I6400)
Modules linked in:
Process swapper/0 (pid: 0, threadinfo=(____ptrval____), task=(____ptrval____), tls=0000000000000000)
Stack : ffffffff80c50000 0000000000000002 ffffffff80e00000 0fffffffffffffff
        ffffffff80c50000 0000000000000001 0000000000000003 ffffffff801bab00
        0000000000000000 ffffffff805d82a8 a8000000020f7bd8 ffffffff801b94f4
        0000000000000000 0000000000000000 ffffffff80c4bc10 5189d95a7a4f4800
        a800000002014300 0000000000000002 0000000000000001 000000000000001f
        ffffffff80e00000 0000000000000004 0000000000000000 ffffffff801bab00
        0000000000000001 ffffffff809ec128 0000000000000000 fffffffffffffffb
        0000000000000001 ffffffff805d7ebc ffffffff80c7b558 ffffffff80c23c80
        a8000000020f7be0 ffffffff80b2fcb8 ffffffff80de0000 ffffffff80c4bec8
        ffffffff80c515c0 ffffffff80112f10 0000000000000000 0000000000000001
        ...
Call Trace:
[<ffffffff801c2398>] handle_percpu_devid_irq+0xb8/0x250
[<ffffffff801bab00>] handle_irq_desc+0x48/0x88
[<ffffffff805d82a8>] gic_irq_dispatch+0xc0/0x288
[<ffffffff801bab00>] handle_irq_desc+0x48/0x88
[<ffffffff809ec128>] do_domain_IRQ+0x28/0x40
[<ffffffff805d7ebc>] plat_irq_dispatch+0x64/0xe8
[<ffffffff80112f10>] handle_int+0x134/0x140
[<ffffffff8011a730>] die+0xa8/0xf8
[<ffffffff80134680>] do_page_fault+0x530/0x540
[<ffffffff8013a1a8>] tlb_do_page_fault_0+0x108/0x110
[<ffffffff801bab00>] handle_irq_desc+0x48/0x88

Code: da000048  de020010  0043102d <dc420000> 00c21016  30420001  d85ffff8  00000000  00000000
~~~

FWIW I'm using a buildroot gcc-14 toolchain but I've seen the same problem on
gcc-13 in previous kgdbtest logs.


Daniel.

Re: [PATCH v4 16/26] genirq: Allow per-cpu interrupt sharing for non-overlapping affinities

[Marc Zyngier]

On Thu, 04 Dec 2025 10:56:13 +0000,
Daniel Thompson <danielt@kernel.org> wrote:
> 
> On Mon, Oct 20, 2025 at 01:29:33PM +0100, Marc Zyngier wrote:
> > Interrupt sharing for percpu-devid interrupts is forbidden, and
> > for good reasons. These are interrupts generated *from* a CPU and
> > handled by itself (timer, for example). Nobody in their right mind
> > would put two devices on the same pin (and if they have, they get to
> > keep the pieces...).
> >
> > But this also prevents more benign cases, where devices are connected
> > to groups of CPUs, and for which the affinities are not overlapping.
> > Effectively, the only thing they share is the interrupt number, and
> > nothing else.
> >
> > Let's tweak the definition of IRQF_SHARED applied to percpu_devid
> > interrupts to allow this particular case. This results in extra
> > validation at the point of the interrupt being setup and freed,
> > as well as a tiny bit of extra complexity for interrupts at handling
> > time (to pick the correct irqaction).
> >
> > Tested-by: Will Deacon <will@kernel.org>
> > Signed-off-by: Marc Zyngier <maz@kernel.org>
> 
> I picked up this patch via linux-next and it appears be causing boot
> regressions on MIPS/qemu. This patch was identified with a bisect and
> a git revert of this patch from the linux-next tip resolves the problem
> (specifically, next-20251204 with git revert bdf4e2ac295f).
> 
> I'm running the code as part of the kgdb test suite but the system
> doesn't survive long enough for kgdb to be involved. In fact I was able
> to reduce things to the following reproduction with all the kgdb pieces
> removed:
> 
>     make malta_kvm_defconfig generic/64r6.config
>     ../scripts/config \
>         --enable WERROR --enable CPU_MIPS64_R6 --enable MIPS_CPS \
> 	--enable BLK_DEV_INITRD --set-val FRAME_WARN 2048
>     make olddefconfig
>     make -j$(nproc) all
>     qemu-system-mips64el -cpu I6400 -M malta -m 1G -smp 2 \
>         -kernel vmlinux -nographic \
> 	-append " console=ttyS0,115200 clk_ignore_unused"

Many thanks for the minimal reproducer, that really helped a lot!

[...]

> CPU 0 Unable to handle kernel paging request at virtual address 0000000000000000, epc == ffffffff801c2398, ra == ffffffff801bab00
> Oops[#1]:
> CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.18.0-next-20251204 #20 NONE
> Hardware name: mti,malta
> $ 0   : 0000000000000000 0000000000000001 0000000000000000 0000000000000000
> $ 4   : 0000000000000001 a8000000020e8008 0000000000000000 ffffffff80c23b80
> $ 8   : 0000000000000004 0000000000000000 0000000000000000 000000000000002f
> $12   : a8000000020f4000 0000000000003ff0 0000000000003000 0000000000000003
> $16   : ffffffff80d095c0 ffffffff80ceb410 0000000000000019 ffffffff80c378c0
> $20   : ffffffff80c4bec8 0000000000000000 ffffffff80e00000 ffffffff80de0000
> $24   : 0000000000000000 0000000000000010
> $28   : ffffffff80c20000 a8000000020f7ec0 a800000000e12fcd ffffffff801bab00
> epc   : ffffffff801c2398 handle_percpu_devid_irq+0xb8/0x250
> ra    : ffffffff801bab00 handle_irq_desc+0x48/0x88
> Status: 1400a4e2	KX SX UX KERNEL EXL
> Cause : 00800408 (ExcCode 02)
> BadVA : 0000000000000000
> PrId  : 0001a900 (MIPS I6400)
> Modules linked in:
> Process swapper/0 (pid: 0, threadinfo=(____ptrval____), task=(____ptrval____), tls=0000000000000000)
> Stack : ffffffff80c35a2c 0000000000000002 ffffffff80e00000 0fffffffffffffff
>         ffffffff80c50000 0000000000000001 0000000000000003 ffffffff801bab00
>         0000000000000000 ffffffff805d82a8 0000000000000000 0000000000000008
>         0000000000000000 0000000000000000 0000000000000000 5189d95a7a4f4800
>         a800000002014300 0000000000000002 0000000000000001 000000000000001f
>         ffffffff80e00000 0000000000000004 0000000000000000 ffffffff801bab00
>         0000000000000000 ffffffff809ec128 0000000000000001 fffffffffffffffb
>         0000000000000001 ffffffff805d7ebc 0000000000000000 0000000000000000
>         ffffffff80c23c80 ffffffff80c50000 ffffffff80de0000 ffffffff80db0000
>         0000000000000000 ffffffff80112f10 ffffffff80c23c80 0000000000000000
> Call Trace:
> [<ffffffff801c2398>] handle_percpu_devid_irq+0xb8/0x250
> [<ffffffff801bab00>] handle_irq_desc+0x48/0x88
> [<ffffffff805d82a8>] gic_irq_dispatch+0xc0/0x288
> [<ffffffff801bab00>] handle_irq_desc+0x48/0x88
> [<ffffffff809ec128>] do_domain_IRQ+0x28/0x40
> [<ffffffff805d7ebc>] plat_irq_dispatch+0x64/0xe8
> [<ffffffff80112f10>] handle_int+0x134/0x140
> [<ffffffff80110dc8>] calibrate_delay+0x158/0x290
> [<ffffffff80d58e48>] start_kernel+0x754/0x7a4

This hack fixes it for me, but really, mips needs to grow up and stop
using these antiquated APIs.

Can please you give it a go?

Thanks,

	M.

diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 0bb29316b4362..8b1b4c8a4f54c 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -2470,6 +2470,9 @@ int setup_percpu_irq(unsigned int irq, struct irqaction *act)
 	if (retval < 0)
 		return retval;
 
+	if (!act->affinity)
+		act->affinity = cpu_online_mask;
+
 	retval = __setup_irq(irq, desc, act);
 
 	if (retval)

-- 
Without deviation from the norm, progress is not possible.

Re: [PATCH v4 16/26] genirq: Allow per-cpu interrupt sharing for non-overlapping affinities

[Daniel Thompson]

On Thu, Dec 04, 2025 at 02:21:51PM +0000, Marc Zyngier wrote:
> On Thu, 04 Dec 2025 10:56:13 +0000,
> Daniel Thompson <danielt@kernel.org> wrote:
> > CPU 0 Unable to handle kernel paging request at virtual address 0000000000000000, epc == ffffffff801c2398, ra == ffffffff801bab00
> > Oops[#1]:
> > CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.18.0-next-20251204 #20 NONE
> > Hardware name: mti,malta
> > $ 0   : 0000000000000000 0000000000000001 0000000000000000 0000000000000000
> > $ 4   : 0000000000000001 a8000000020e8008 0000000000000000 ffffffff80c23b80
> > $ 8   : 0000000000000004 0000000000000000 0000000000000000 000000000000002f
> > $12   : a8000000020f4000 0000000000003ff0 0000000000003000 0000000000000003
> > $16   : ffffffff80d095c0 ffffffff80ceb410 0000000000000019 ffffffff80c378c0
> > $20   : ffffffff80c4bec8 0000000000000000 ffffffff80e00000 ffffffff80de0000
> > $24   : 0000000000000000 0000000000000010
> > $28   : ffffffff80c20000 a8000000020f7ec0 a800000000e12fcd ffffffff801bab00
> > epc   : ffffffff801c2398 handle_percpu_devid_irq+0xb8/0x250
> > ra    : ffffffff801bab00 handle_irq_desc+0x48/0x88
> > Status: 1400a4e2	KX SX UX KERNEL EXL
> > Cause : 00800408 (ExcCode 02)
> > BadVA : 0000000000000000
> > PrId  : 0001a900 (MIPS I6400)
> > Modules linked in:
> > Process swapper/0 (pid: 0, threadinfo=(____ptrval____), task=(____ptrval____), tls=0000000000000000)
> > Stack : ffffffff80c35a2c 0000000000000002 ffffffff80e00000 0fffffffffffffff
> >         ffffffff80c50000 0000000000000001 0000000000000003 ffffffff801bab00
> >         0000000000000000 ffffffff805d82a8 0000000000000000 0000000000000008
> >         0000000000000000 0000000000000000 0000000000000000 5189d95a7a4f4800
> >         a800000002014300 0000000000000002 0000000000000001 000000000000001f
> >         ffffffff80e00000 0000000000000004 0000000000000000 ffffffff801bab00
> >         0000000000000000 ffffffff809ec128 0000000000000001 fffffffffffffffb
> >         0000000000000001 ffffffff805d7ebc 0000000000000000 0000000000000000
> >         ffffffff80c23c80 ffffffff80c50000 ffffffff80de0000 ffffffff80db0000
> >         0000000000000000 ffffffff80112f10 ffffffff80c23c80 0000000000000000
> > Call Trace:
> > [<ffffffff801c2398>] handle_percpu_devid_irq+0xb8/0x250
> > [<ffffffff801bab00>] handle_irq_desc+0x48/0x88
> > [<ffffffff805d82a8>] gic_irq_dispatch+0xc0/0x288
> > [<ffffffff801bab00>] handle_irq_desc+0x48/0x88
> > [<ffffffff809ec128>] do_domain_IRQ+0x28/0x40
> > [<ffffffff805d7ebc>] plat_irq_dispatch+0x64/0xe8
> > [<ffffffff80112f10>] handle_int+0x134/0x140
> > [<ffffffff80110dc8>] calibrate_delay+0x158/0x290
> > [<ffffffff80d58e48>] start_kernel+0x754/0x7a4
>
> This hack fixes it for me, but really, mips needs to grow up and stop
> using these antiquated APIs.

I can't comment on that. Literally the only thing I ever do on MIPS is
test kgdb ;-) .


> Can please you give it a go?

Looks good to me.

Local testing on MIPS worked nicely and I got a successful build back
for the kgdb tests:
https://gitlab.com/daniel-thompson/linux/-/pipelines/2196473049


Daniel.