From ee8d41e53efe14bfc5ea5866e1178b06d78a7c95 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 14 Sep 2016 16:18:51 +0200 Subject: [PATCH] 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 Signed-off-by: Christoph Hellwig 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 --- drivers/pci/msi.c | 31 +++++++++++++++++++++++++++++++ include/linux/pci.h | 6 ++++++ 2 files changed, 37 insertions(+) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 06100dde0e86..9da5ecb41f0b 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -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); diff --git a/include/linux/pci.h b/include/linux/pci.h index 0ab835965669..3b0a8004f313 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -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 -- GitLab