pci/msi: Retrieve affinity for a vector

Add a helper to get the affinity mask for a given PCI irq vector.  For MSI or
MSI-X vectors these are stored by the IRQ core, while for legacy interrupts
we will always return cpu_possible_map.

[hch: updated to follow the style of pci_irq_vector()]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: axboe@fb.com
Cc: keith.busch@intel.com
Cc: agordeev@redhat.com
Cc: linux-block@vger.kernel.org
Link: http://lkml.kernel.org/r/1473862739-15032-6-git-send-email-hch@lst.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Thomas Gleixner 2016-09-14 16:18:51 +02:00
parent 44082fd670
commit ee8d41e53e
2 changed files with 37 additions and 0 deletions

View File

@ -1270,6 +1270,37 @@ int pci_irq_vector(struct pci_dev *dev, unsigned int nr)
}
EXPORT_SYMBOL(pci_irq_vector);
/**
* pci_irq_get_affinity - return the affinity of a particular msi vector
* @dev: PCI device to operate on
* @nr: device-relative interrupt vector index (0-based).
*/
const struct cpumask *pci_irq_get_affinity(struct pci_dev *dev, int nr)
{
if (dev->msix_enabled) {
struct msi_desc *entry;
int i = 0;
for_each_pci_msi_entry(entry, dev) {
if (i == nr)
return entry->affinity;
i++;
}
WARN_ON_ONCE(1);
return NULL;
} else if (dev->msi_enabled) {
struct msi_desc *entry = first_pci_msi_entry(dev);
if (WARN_ON_ONCE(!entry || nr >= entry->nvec_used))
return NULL;
return &entry->affinity[nr];
} else {
return cpu_possible_mask;
}
}
EXPORT_SYMBOL(pci_irq_get_affinity);
struct pci_dev *msi_desc_to_pci_dev(struct msi_desc *desc)
{
return to_pci_dev(desc->dev);

View File

@ -1300,6 +1300,7 @@ int pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
unsigned int max_vecs, unsigned int flags);
void pci_free_irq_vectors(struct pci_dev *dev);
int pci_irq_vector(struct pci_dev *dev, unsigned int nr);
const struct cpumask *pci_irq_get_affinity(struct pci_dev *pdev, int vec);
#else
static inline int pci_msi_vec_count(struct pci_dev *dev) { return -ENOSYS; }
@ -1342,6 +1343,11 @@ static inline int pci_irq_vector(struct pci_dev *dev, unsigned int nr)
return -EINVAL;
return dev->irq;
}
static inline const struct cpumask *pci_irq_get_affinity(struct pci_dev *pdev,
int vec)
{
return cpu_possible_mask;
}
#endif
#ifdef CONFIG_PCIEPORTBUS