[PATCH 3/8] genirq/affinity: factor out a irq_affinity_set helper

From: Christoph Hellwig
Date: Sat Jun 03 2017 - 10:04:37 EST


Factor out code from the x86 cpu hot plug code to program the affinity
for a vector for a hot plug / hot unplug event.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
arch/x86/kernel/irq.c | 23 ++---------------------
include/linux/interrupt.h | 1 +
kernel/irq/affinity.c | 28 ++++++++++++++++++++++++++++
3 files changed, 31 insertions(+), 21 deletions(-)

diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index f34fe7444836..a54eac5d81b3 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -437,7 +437,6 @@ void fixup_irqs(void)
struct irq_desc *desc;
struct irq_data *data;
struct irq_chip *chip;
- int ret;

for_each_irq_desc(irq, desc) {
int break_affinity = 0;
@@ -482,26 +481,8 @@ void fixup_irqs(void)
continue;
}

- if (!irqd_can_move_in_process_context(data) && chip->irq_mask)
- chip->irq_mask(data);
-
- if (chip->irq_set_affinity) {
- ret = chip->irq_set_affinity(data, affinity, true);
- if (ret == -ENOSPC)
- pr_crit("IRQ %d set affinity failed because there are no available vectors. The device assigned to this IRQ is unstable.\n", irq);
- } else {
- if (!(warned++))
- set_affinity = 0;
- }
-
- /*
- * We unmask if the irq was not marked masked by the
- * core code. That respects the lazy irq disable
- * behaviour.
- */
- if (!irqd_can_move_in_process_context(data) &&
- !irqd_irq_masked(data) && chip->irq_unmask)
- chip->irq_unmask(data);
+ if (!irq_affinity_set(irq, desc, affinity) && !warned++)
+ set_affinity = 0;

raw_spin_unlock(&desc->lock);

diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index a6fba4804672..afd3aa33e9b0 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -292,6 +292,7 @@ irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify);

struct cpumask *irq_create_affinity_masks(int nvec, const struct irq_affinity *affd);
int irq_calc_affinity_vectors(int maxvec, const struct irq_affinity *affd);
+bool irq_affinity_set(int irq, struct irq_desc *desc, const cpumask_t *mask);

#else /* CONFIG_SMP */

diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c
index e2d356dd7581..3cec0042fad2 100644
--- a/kernel/irq/affinity.c
+++ b/kernel/irq/affinity.c
@@ -1,8 +1,36 @@

#include <linux/interrupt.h>
+#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/cpu.h>
+#include "internals.h"
+
+bool irq_affinity_set(int irq, struct irq_desc *desc, const cpumask_t *mask)
+{
+ struct irq_data *data = irq_desc_get_irq_data(desc);
+ struct irq_chip *chip = irq_data_get_irq_chip(data);
+ bool ret = false;
+
+ if (!irq_can_move_pcntxt(data) && chip->irq_mask)
+ chip->irq_mask(data);
+
+ if (chip->irq_set_affinity) {
+ if (chip->irq_set_affinity(data, mask, true) == -ENOSPC)
+ pr_crit("IRQ %d set affinity failed because there are no available vectors. The device assigned to this IRQ is unstable.\n", irq);
+ ret = true;
+ }
+
+ /*
+ * We unmask if the irq was not marked masked by the core code.
+ * That respects the lazy irq disable behaviour.
+ */
+ if (!irq_can_move_pcntxt(data) &&
+ !irqd_irq_masked(data) && chip->irq_unmask)
+ chip->irq_unmask(data);
+
+ return ret;
+}

static void irq_spread_init_one(struct cpumask *irqmsk, struct cpumask *nmsk,
int cpus_per_vec)
--
2.11.0