[PATCH V3 2/5] genirq/affinity: store irq set vectors in 'struct irq_affinity'

Ming Lei
2019-02-13T10:51:10Z

Currently the array of irq set vectors is provided by driver.

irq_create_affinity_masks() can be simplied a bit by treating the
non-irq-set case as single irq set.

So move this array into 'struct irq_affinity', and pre-define the max
set number as 4, which should be enough for normal cases.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
drivers/nvme/host/pci.c | 5 ++---
include/linux/interrupt.h | 6 ++++--
kernel/irq/affinity.c | 18 +++++++++++-------
3 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 022ea1ee63f8..0086bdf80ea1 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -2081,12 +2081,11 @@ static void nvme_calc_io_queues(struct nvme_dev *dev, unsigned int irq_queues)
static int nvme_setup_irqs(struct nvme_dev *dev, unsigned int nr_io_queues)
{
struct pci_dev *pdev = to_pci_dev(dev->dev);
- int irq_sets[2];
struct irq_affinity affd = {
.pre_vectors = 1,
- .nr_sets = ARRAY_SIZE(irq_sets),
- .sets = irq_sets,
+ .nr_sets = 2,
};
+ int *irq_sets = affd.set_vectors;
int result = 0;
unsigned int irq_queues, this_p_queues;

diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 1ed1014c9684..a20150627a32 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -259,6 +259,8 @@ struct irq_affinity_notify {
void (*release)(struct kref *ref);
};

+#define IRQ_MAX_SETS 4
+
/**
* struct irq_affinity - Description for automatic irq affinity assignements
* @pre_vectors: Don't apply affinity to @pre_vectors at beginning of
@@ -266,13 +268,13 @@ struct irq_affinity_notify {
* @post_vectors: Don't apply affinity to @post_vectors at end of
* the MSI(-X) vector space
* @nr_sets: Length of passed in *sets array
- * @sets: Number of affinitized sets
+ * @set_vectors: Number of affinitized sets
*/
struct irq_affinity {
int pre_vectors;
int post_vectors;
int nr_sets;
- int *sets;
+ int set_vectors[IRQ_MAX_SETS];
};

/**
diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c
index 9200d3b26f7d..b868b9d3df7f 100644
--- a/kernel/irq/affinity.c
+++ b/kernel/irq/affinity.c
@@ -244,7 +244,7 @@ irq_create_affinity_masks(int nvecs, struct irq_affinity *affd)
int affvecs = nvecs - affd->pre_vectors - affd->post_vectors;
int curvec, usedvecs;
struct irq_affinity_desc *masks = NULL;
- int i, nr_sets;
+ int i;

/*
* If there aren't any vectors left after applying the pre/post
@@ -253,6 +253,9 @@ irq_create_affinity_masks(int nvecs, struct irq_affinity *affd)
if (nvecs == affd->pre_vectors + affd->post_vectors)
return NULL;

+ if (affd->nr_sets > IRQ_MAX_SETS)
+ return NULL;
+
masks = kcalloc(nvecs, sizeof(*masks), GFP_KERNEL);
if (!masks)
return NULL;
@@ -264,12 +267,13 @@ irq_create_affinity_masks(int nvecs, struct irq_affinity *affd)
* Spread on present CPUs starting from affd->pre_vectors. If we
* have multiple sets, build each sets affinity mask separately.
*/
- nr_sets = affd->nr_sets;
- if (!nr_sets)
- nr_sets = 1;
+ if (!affd->nr_sets) {
+ affd->nr_sets = 1;
+ affd->set_vectors[0] = affvecs;
+ }

- for (i = 0, usedvecs = 0; i < nr_sets; i++) {
- int this_vecs = affd->sets ? affd->sets[i] : affvecs;
+ for (i = 0, usedvecs = 0; i < affd->nr_sets; i++) {
+ int this_vecs = affd->set_vectors[i];
int ret;

ret = irq_build_affinity_masks(affd, curvec, this_vecs,
@@ -316,7 +320,7 @@ int irq_calc_affinity_vectors(int minvec, int maxvec, const struct irq_affinity
int i;

for (i = 0, set_vecs = 0; i < affd->nr_sets; i++)
- set_vecs += affd->sets[i];
+ set_vecs += affd->set_vectors[i];
} else {
get_online_cpus();
set_vecs = cpumask_weight(cpu_possible_mask);
--
2.9.5