diff mbox series

[06/13] genirq: Add default_affinity argument to __irq_alloc_descs()

Message ID 20201005152856.974112-6-dwmw2@infradead.org (mailing list archive)
State New, archived
Headers show
Series Fix per-domain IRQ affinity, allow >255 CPUs on x86 without IRQ remapping | expand

Commit Message

David Woodhouse Oct. 5, 2020, 3:28 p.m. UTC 
From: David Woodhouse <dwmw@amazon.co.uk>

It already takes an array of affinities for each individual irq being
allocated but that's awkward to allocate and populate in the case
where they're all the same and inherited from the irqdomain, so pass
the default in separately as a simple cpumask.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
---
 include/linux/irq.h    | 10 ++++++----
 kernel/irq/devres.c    |  8 ++++++--
 kernel/irq/irqdesc.c   | 10 ++++++++--
 kernel/irq/irqdomain.c |  6 +++---
 4 files changed, 23 insertions(+), 11 deletions(-)

Comments

Thomas Gleixner Oct. 6, 2020, 9:06 p.m. UTC | #1 
On Mon, Oct 05 2020 at 16:28, David Woodhouse wrote:
> From: David Woodhouse <dwmw@amazon.co.uk>
> It already takes an array of affinities for each individual irq being
> allocated but that's awkward to allocate and populate in the case
> where they're all the same and inherited from the irqdomain, so pass
> the default in separately as a simple cpumask.

So we need another cpumask argument exposed to the world just because
it's so hard to extend struct irq_affinity_desc so it supports that use
case as well. It's not written in stone that this struct can only
support arrays.

> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
> ---
>  include/linux/irq.h    | 10 ++++++----
>  kernel/irq/devres.c    |  8 ++++++--
>  kernel/irq/irqdesc.c   | 10 ++++++++--
>  kernel/irq/irqdomain.c |  6 +++---

git grep __irq_alloc_descs() might help you to find _all_ instances ...

Thanks,

        tglx
diff mbox series

Patch

diff --git a/include/linux/irq.h b/include/linux/irq.h
index 1b7f4dfee35b..6e119594d35d 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -897,15 +897,17 @@  unsigned int arch_dynirq_lower_bound(unsigned int from);
 
 int __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
 		      struct module *owner,
-		      const struct irq_affinity_desc *affinity);
+		      const struct irq_affinity_desc *affinity,
+		      const struct cpumask *default_affinity);
 
 int __devm_irq_alloc_descs(struct device *dev, int irq, unsigned int from,
 			   unsigned int cnt, int node, struct module *owner,
-			   const struct irq_affinity_desc *affinity);
+			   const struct irq_affinity_desc *affinity,
+			   const struct cpumask *default_affinity);
 
 /* use macros to avoid needing export.h for THIS_MODULE */
 #define irq_alloc_descs(irq, from, cnt, node)	\
-	__irq_alloc_descs(irq, from, cnt, node, THIS_MODULE, NULL)
+	__irq_alloc_descs(irq, from, cnt, node, THIS_MODULE, NULL, NULL)
 
 #define irq_alloc_desc(node)			\
 	irq_alloc_descs(-1, 0, 1, node)
@@ -920,7 +922,7 @@  int __devm_irq_alloc_descs(struct device *dev, int irq, unsigned int from,
 	irq_alloc_descs(-1, from, cnt, node)
 
 #define devm_irq_alloc_descs(dev, irq, from, cnt, node)		\
-	__devm_irq_alloc_descs(dev, irq, from, cnt, node, THIS_MODULE, NULL)
+	__devm_irq_alloc_descs(dev, irq, from, cnt, node, THIS_MODULE, NULL, NULL)
 
 #define devm_irq_alloc_desc(dev, node)				\
 	devm_irq_alloc_descs(dev, -1, 0, 1, node)
diff --git a/kernel/irq/devres.c b/kernel/irq/devres.c
index f6e5515ee077..079339decc23 100644
--- a/kernel/irq/devres.c
+++ b/kernel/irq/devres.c
@@ -170,6 +170,8 @@  static void devm_irq_desc_release(struct device *dev, void *res)
  * @affinity:	Optional pointer to an irq_affinity_desc array of size @cnt
  *		which hints where the irq descriptors should be allocated
  *		and which default affinities to use
+ * @default_affinity: Optional pointer to a cpumask indicating the default
+ *              affinity to use where not specified by the @affinity array
  *
  * Returns the first irq number or error code.
  *
@@ -177,7 +179,8 @@  static void devm_irq_desc_release(struct device *dev, void *res)
  */
 int __devm_irq_alloc_descs(struct device *dev, int irq, unsigned int from,
 			   unsigned int cnt, int node, struct module *owner,
-			   const struct irq_affinity_desc *affinity)
+			   const struct irq_affinity_desc *affinity,
+			   const struct cpumask *default_affinity)
 {
 	struct irq_desc_devres *dr;
 	int base;
@@ -186,7 +189,8 @@  int __devm_irq_alloc_descs(struct device *dev, int irq, unsigned int from,
 	if (!dr)
 		return -ENOMEM;
 
-	base = __irq_alloc_descs(irq, from, cnt, node, owner, affinity);
+	base = __irq_alloc_descs(irq, from, cnt, node, owner, affinity,
+				 default_affinity);
 	if (base < 0) {
 		devres_free(dr);
 		return base;
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 4ac91b9fc618..fcc3b8a1fe01 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -770,15 +770,21 @@  EXPORT_SYMBOL_GPL(irq_free_descs);
  * @affinity:	Optional pointer to an affinity mask array of size @cnt which
  *		hints where the irq descriptors should be allocated and which
  *		default affinities to use
+ * @default_affinity: Optional pointer to a cpumask indicating the default
+ *              affinity where not specified in the @affinity array
  *
  * Returns the first irq number or error code
  */
 int __ref
 __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
-		  struct module *owner, const struct irq_affinity_desc *affinity)
+		  struct module *owner, const struct irq_affinity_desc *affinity,
+		  const struct cpumask *default_affinity)
 {
 	int start, ret;
 
+	if (!default_affinity)
+		default_affinity = irq_default_affinity;
+
 	if (!cnt)
 		return -EINVAL;
 
@@ -808,7 +814,7 @@  __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
 		if (ret)
 			goto unlock;
 	}
-	ret = alloc_descs(start, cnt, node, affinity, irq_default_affinity, owner);
+	ret = alloc_descs(start, cnt, node, affinity, default_affinity, owner);
 unlock:
 	mutex_unlock(&sparse_irq_lock);
 	return ret;
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 76cd7ebd1178..c93e00ca11d8 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -1017,16 +1017,16 @@  int irq_domain_alloc_descs(int virq, unsigned int cnt, irq_hw_number_t hwirq,
 
 	if (virq >= 0) {
 		virq = __irq_alloc_descs(virq, virq, cnt, node, THIS_MODULE,
-					 affinity);
+					 affinity, NULL);
 	} else {
 		hint = hwirq % nr_irqs;
 		if (hint == 0)
 			hint++;
 		virq = __irq_alloc_descs(-1, hint, cnt, node, THIS_MODULE,
-					 affinity);
+					 affinity, NULL);
 		if (virq <= 0 && hint > 1) {
 			virq = __irq_alloc_descs(-1, 1, cnt, node, THIS_MODULE,
-						 affinity);
+						 affinity, NULL);
 		}
 	}