| Message ID | 1468315218-20490-6-git-send-email-hch@lst.de |
|---|---|
| State | Accepted |
| Headers | show |
On Tue, Jul 12, 2016 at 06:20:18PM +0900, Christoph Hellwig wrote: > Set the affinity_mask in the PCI device before allocating vectors so that > the affinity can be propagated through the MSI descriptor structures to > the core IRQ code. To facilitate this new __pci_enable_msi_range and > __pci_enable_msix_range helpers are factored out of their not prefixed > variants which assigning the new irq affinity mask in the PCI device > so that the low-level interrupt code can perform the interrupt affinity > assignment and do node-local allocations. > > A new PCI_IRQ_NOAFFINITY flag is added to pci_alloc_irq_vectors so that > this function can also be used by drivers that don't wish to use the > automatic affinity assignment. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > Documentation/PCI/MSI-HOWTO.txt | 3 + > drivers/pci/msi.c | 127 ++++++++++++++++++++++++++-------------- > include/linux/pci.h | 2 + > 3 files changed, 89 insertions(+), 43 deletions(-) > > diff --git a/Documentation/PCI/MSI-HOWTO.txt b/Documentation/PCI/MSI-HOWTO.txt > index 0af91e8..16e9187 100644 > --- a/Documentation/PCI/MSI-HOWTO.txt > +++ b/Documentation/PCI/MSI-HOWTO.txt > @@ -97,6 +97,9 @@ The flags argument should normally be set to 0, but can be used to pass the > PCI_IRQ_NOMSI and PCI_IRQ_NOMSIX flag in case a device claims to support > MSI or MSI-X, but the support is broken, or to pass PCI_IRQ_NOLEGACY in > case the device does not support legacy interrupt lines. > +By default this function will spread the interrupts around the available > +CPUs, but this feature can be disabled by passing the PCI_IRQ_NOAFFINITY > +flag. > > To get the Linux IRQ numbers passed to request_irq and free_irq > and the vectors use the following function: > diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c > index 00657bf..692deff 100644 > --- a/drivers/pci/msi.c > +++ b/drivers/pci/msi.c > @@ -569,6 +569,7 @@ static struct msi_desc *msi_setup_entry(struct pci_dev *dev, int nvec) > entry->msi_attrib.multi_cap = (control & PCI_MSI_FLAGS_QMASK) >> 1; > entry->msi_attrib.multiple = ilog2(__roundup_pow_of_two(nvec)); > entry->nvec_used = nvec; > + entry->affinity = dev->irq_affinity; > > if (control & PCI_MSI_FLAGS_64BIT) > entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_64; > @@ -680,10 +681,18 @@ static void __iomem *msix_map_region(struct pci_dev *dev, unsigned nr_entries) > static int msix_setup_entries(struct pci_dev *dev, void __iomem *base, > struct msix_entry *entries, int nvec) > { > + const struct cpumask *mask = NULL; > struct msi_desc *entry; > - int i; > + int cpu = -1, i; > > for (i = 0; i < nvec; i++) { > + if (dev->irq_affinity) { > + cpu = cpumask_next(cpu, dev->irq_affinity); > + if (cpu >= nr_cpu_ids) > + cpu = cpumask_first(dev->irq_affinity); > + mask = cpumask_of(cpu); > + } > + > entry = alloc_msi_entry(&dev->dev); > if (!entry) { > if (!i) > @@ -703,6 +712,7 @@ static int msix_setup_entries(struct pci_dev *dev, void __iomem *base, > entry->msi_attrib.default_irq = dev->irq; > entry->mask_base = base; > entry->nvec_used = 1; > + entry->affinity = mask; > > list_add_tail(&entry->list, dev_to_msi_list(&dev->dev)); > } > @@ -1028,19 +1038,8 @@ int pci_msi_enabled(void) > } > EXPORT_SYMBOL(pci_msi_enabled); > > -/** > - * pci_enable_msi_range - configure device's MSI capability structure > - * @dev: device to configure > - * @minvec: minimal number of interrupts to configure > - * @maxvec: maximum number of interrupts to configure > - * > - * This function tries to allocate a maximum possible number of interrupts in a > - * range between @minvec and @maxvec. It returns a negative errno if an error > - * occurs. If it succeeds, it returns the actual number of interrupts allocated > - * and updates the @dev's irq member to the lowest new interrupt number; > - * the other interrupt numbers allocated to this device are consecutive. > - **/ > -int pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec) > +static int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec, > + unsigned int flags) > { > int nvec; > int rc; > @@ -1068,20 +1067,77 @@ int pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec) > else if (nvec > maxvec) > nvec = maxvec; > > - do { > + for (;;) { > + if (!(flags & PCI_IRQ_NOAFFINITY)) { > + dev->irq_affinity = irq_create_affinity_mask(&nvec); > + if (nvec < minvec) > + return -ENOSPC; > + } > + > rc = msi_capability_init(dev, nvec); > - if (rc < 0) { > + if (rc == 0) > + return nvec; > + > + kfree(dev->irq_affinity); > + dev->irq_affinity = NULL; > + > + if (rc < 0) > return rc; > - } else if (rc > 0) { > - if (rc < minvec) > + if (rc < minvec) > + return -ENOSPC; > + nvec = rc; > + } > +} > + > +/** > + * pci_enable_msi_range - configure device's MSI capability structure > + * @dev: device to configure > + * @minvec: minimal number of interrupts to configure > + * @maxvec: maximum number of interrupts to configure > + * > + * This function tries to allocate a maximum possible number of interrupts in a > + * range between @minvec and @maxvec. It returns a negative errno if an error > + * occurs. If it succeeds, it returns the actual number of interrupts allocated > + * and updates the @dev's irq member to the lowest new interrupt number; > + * the other interrupt numbers allocated to this device are consecutive. > + **/ > +int pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec) > +{ > + return __pci_enable_msi_range(dev, minvec, maxvec, PCI_IRQ_NOAFFINITY); > +} > +EXPORT_SYMBOL(pci_enable_msi_range); > + > +static int __pci_enable_msix_range(struct pci_dev *dev, > + struct msix_entry *entries, int minvec, int maxvec, > + unsigned int flags) > +{ > + int nvec = maxvec; > + int rc; > + > + if (maxvec < minvec) > + return -ERANGE; > + > + for (;;) { > + if (!(flags & PCI_IRQ_NOAFFINITY)) { > + dev->irq_affinity = irq_create_affinity_mask(&nvec); > + if (nvec < minvec) > return -ENOSPC; > - nvec = rc; > } > - } while (rc); > > - return nvec; > + rc = pci_enable_msix(dev, entries, nvec); > + if (rc == 0) > + return nvec; > + > + kfree(dev->irq_affinity); > + dev->irq_affinity = NULL; > + > + if (rc < 0) > + return rc; > + if (rc < minvec) > + return -ENOSPC; > + nvec = rc; > + } > } > -EXPORT_SYMBOL(pci_enable_msi_range); > > /** > * pci_enable_msix_range - configure device's MSI-X capability structure > @@ -1099,26 +1155,10 @@ EXPORT_SYMBOL(pci_enable_msi_range); > * with new allocated MSI-X interrupts. > **/ > int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries, > - int minvec, int maxvec) > + int minvec, int maxvec) > { > - int nvec = maxvec; > - int rc; > - > - if (maxvec < minvec) > - return -ERANGE; > - > - do { > - rc = pci_enable_msix(dev, entries, nvec); > - if (rc < 0) { > - return rc; > - } else if (rc > 0) { > - if (rc < minvec) > - return -ENOSPC; > - nvec = rc; > - } > - } while (rc); > - > - return nvec; > + return __pci_enable_msix_range(dev, entries, minvec, maxvec, > + PCI_IRQ_NOAFFINITY); > } > EXPORT_SYMBOL(pci_enable_msix_range); > > @@ -1145,13 +1185,14 @@ int pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs, > int vecs = -ENOSPC; > > if (!(flags & PCI_IRQ_NOMSIX)) { > - vecs = pci_enable_msix_range(dev, NULL, min_vecs, max_vecs); > + vecs = __pci_enable_msix_range(dev, NULL, min_vecs, max_vecs, > + flags); > if (vecs > 0) > return vecs; > } > > if (!(flags & PCI_IRQ_NOMSI)) { > - vecs = pci_enable_msi_range(dev, min_vecs, max_vecs); > + vecs = __pci_enable_msi_range(dev, min_vecs, max_vecs, flags); > if (vecs > 0) > return vecs; > } > diff --git a/include/linux/pci.h b/include/linux/pci.h > index 52ecd49..f140661 100644 > --- a/include/linux/pci.h > +++ b/include/linux/pci.h > @@ -320,6 +320,7 @@ struct pci_dev { > * directly, use the values stored here. They might be different! > */ > unsigned int irq; > + struct cpumask *irq_affinity; > struct resource resource[DEVICE_COUNT_RESOURCE]; /* I/O and memory regions + expansion ROMs */ > > bool match_driver; /* Skip attaching driver */ > @@ -1240,6 +1241,7 @@ int pci_set_vga_state(struct pci_dev *pdev, bool decode, > #define PCI_IRQ_NOLEGACY (1 << 0) /* don't use legacy interrupts */ > #define PCI_IRQ_NOMSI (1 << 1) /* don't use MSI interrupts */ > #define PCI_IRQ_NOMSIX (1 << 2) /* don't use MSI-X interrupts */ > +#define PCI_IRQ_NOAFFINITY (1 << 3) /* don't auto-assign affinity */ > > /* kmem_cache style wrapper around pci_alloc_consistent() */ > > -- > 2.1.4 > With, or without my -else nit: Reviewed-by: Alexander Gordeev <agordeev@redhat.com> -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/PCI/MSI-HOWTO.txt b/Documentation/PCI/MSI-HOWTO.txt index 0af91e8..16e9187 100644 --- a/Documentation/PCI/MSI-HOWTO.txt +++ b/Documentation/PCI/MSI-HOWTO.txt @@ -97,6 +97,9 @@ The flags argument should normally be set to 0, but can be used to pass the PCI_IRQ_NOMSI and PCI_IRQ_NOMSIX flag in case a device claims to support MSI or MSI-X, but the support is broken, or to pass PCI_IRQ_NOLEGACY in case the device does not support legacy interrupt lines. +By default this function will spread the interrupts around the available +CPUs, but this feature can be disabled by passing the PCI_IRQ_NOAFFINITY +flag. To get the Linux IRQ numbers passed to request_irq and free_irq and the vectors use the following function: diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 00657bf..692deff 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -569,6 +569,7 @@ static struct msi_desc *msi_setup_entry(struct pci_dev *dev, int nvec) entry->msi_attrib.multi_cap = (control & PCI_MSI_FLAGS_QMASK) >> 1; entry->msi_attrib.multiple = ilog2(__roundup_pow_of_two(nvec)); entry->nvec_used = nvec; + entry->affinity = dev->irq_affinity; if (control & PCI_MSI_FLAGS_64BIT) entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_64; @@ -680,10 +681,18 @@ static void __iomem *msix_map_region(struct pci_dev *dev, unsigned nr_entries) static int msix_setup_entries(struct pci_dev *dev, void __iomem *base, struct msix_entry *entries, int nvec) { + const struct cpumask *mask = NULL; struct msi_desc *entry; - int i; + int cpu = -1, i; for (i = 0; i < nvec; i++) { + if (dev->irq_affinity) { + cpu = cpumask_next(cpu, dev->irq_affinity); + if (cpu >= nr_cpu_ids) + cpu = cpumask_first(dev->irq_affinity); + mask = cpumask_of(cpu); + } + entry = alloc_msi_entry(&dev->dev); if (!entry) { if (!i) @@ -703,6 +712,7 @@ static int msix_setup_entries(struct pci_dev *dev, void __iomem *base, entry->msi_attrib.default_irq = dev->irq; entry->mask_base = base; entry->nvec_used = 1; + entry->affinity = mask; list_add_tail(&entry->list, dev_to_msi_list(&dev->dev)); } @@ -1028,19 +1038,8 @@ int pci_msi_enabled(void) } EXPORT_SYMBOL(pci_msi_enabled); -/** - * pci_enable_msi_range - configure device's MSI capability structure - * @dev: device to configure - * @minvec: minimal number of interrupts to configure - * @maxvec: maximum number of interrupts to configure - * - * This function tries to allocate a maximum possible number of interrupts in a - * range between @minvec and @maxvec. It returns a negative errno if an error - * occurs. If it succeeds, it returns the actual number of interrupts allocated - * and updates the @dev's irq member to the lowest new interrupt number; - * the other interrupt numbers allocated to this device are consecutive. - **/ -int pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec) +static int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec, + unsigned int flags) { int nvec; int rc; @@ -1068,20 +1067,77 @@ int pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec) else if (nvec > maxvec) nvec = maxvec; - do { + for (;;) { + if (!(flags & PCI_IRQ_NOAFFINITY)) { + dev->irq_affinity = irq_create_affinity_mask(&nvec); + if (nvec < minvec) + return -ENOSPC; + } + rc = msi_capability_init(dev, nvec); - if (rc < 0) { + if (rc == 0) + return nvec; + + kfree(dev->irq_affinity); + dev->irq_affinity = NULL; + + if (rc < 0) return rc; - } else if (rc > 0) { - if (rc < minvec) + if (rc < minvec) + return -ENOSPC; + nvec = rc; + } +} + +/** + * pci_enable_msi_range - configure device's MSI capability structure + * @dev: device to configure + * @minvec: minimal number of interrupts to configure + * @maxvec: maximum number of interrupts to configure + * + * This function tries to allocate a maximum possible number of interrupts in a + * range between @minvec and @maxvec. It returns a negative errno if an error + * occurs. If it succeeds, it returns the actual number of interrupts allocated + * and updates the @dev's irq member to the lowest new interrupt number; + * the other interrupt numbers allocated to this device are consecutive. + **/ +int pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec) +{ + return __pci_enable_msi_range(dev, minvec, maxvec, PCI_IRQ_NOAFFINITY); +} +EXPORT_SYMBOL(pci_enable_msi_range); + +static int __pci_enable_msix_range(struct pci_dev *dev, + struct msix_entry *entries, int minvec, int maxvec, + unsigned int flags) +{ + int nvec = maxvec; + int rc; + + if (maxvec < minvec) + return -ERANGE; + + for (;;) { + if (!(flags & PCI_IRQ_NOAFFINITY)) { + dev->irq_affinity = irq_create_affinity_mask(&nvec); + if (nvec < minvec) return -ENOSPC; - nvec = rc; } - } while (rc); - return nvec; + rc = pci_enable_msix(dev, entries, nvec); + if (rc == 0) + return nvec; + + kfree(dev->irq_affinity); + dev->irq_affinity = NULL; + + if (rc < 0) + return rc; + if (rc < minvec) + return -ENOSPC; + nvec = rc; + } } -EXPORT_SYMBOL(pci_enable_msi_range); /** * pci_enable_msix_range - configure device's MSI-X capability structure @@ -1099,26 +1155,10 @@ EXPORT_SYMBOL(pci_enable_msi_range); * with new allocated MSI-X interrupts. **/ int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries, - int minvec, int maxvec) + int minvec, int maxvec) { - int nvec = maxvec; - int rc; - - if (maxvec < minvec) - return -ERANGE; - - do { - rc = pci_enable_msix(dev, entries, nvec); - if (rc < 0) { - return rc; - } else if (rc > 0) { - if (rc < minvec) - return -ENOSPC; - nvec = rc; - } - } while (rc); - - return nvec; + return __pci_enable_msix_range(dev, entries, minvec, maxvec, + PCI_IRQ_NOAFFINITY); } EXPORT_SYMBOL(pci_enable_msix_range); @@ -1145,13 +1185,14 @@ int pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs, int vecs = -ENOSPC; if (!(flags & PCI_IRQ_NOMSIX)) { - vecs = pci_enable_msix_range(dev, NULL, min_vecs, max_vecs); + vecs = __pci_enable_msix_range(dev, NULL, min_vecs, max_vecs, + flags); if (vecs > 0) return vecs; } if (!(flags & PCI_IRQ_NOMSI)) { - vecs = pci_enable_msi_range(dev, min_vecs, max_vecs); + vecs = __pci_enable_msi_range(dev, min_vecs, max_vecs, flags); if (vecs > 0) return vecs; } diff --git a/include/linux/pci.h b/include/linux/pci.h index 52ecd49..f140661 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -320,6 +320,7 @@ struct pci_dev { * directly, use the values stored here. They might be different! */ unsigned int irq; + struct cpumask *irq_affinity; struct resource resource[DEVICE_COUNT_RESOURCE]; /* I/O and memory regions + expansion ROMs */ bool match_driver; /* Skip attaching driver */ @@ -1240,6 +1241,7 @@ int pci_set_vga_state(struct pci_dev *pdev, bool decode, #define PCI_IRQ_NOLEGACY (1 << 0) /* don't use legacy interrupts */ #define PCI_IRQ_NOMSI (1 << 1) /* don't use MSI interrupts */ #define PCI_IRQ_NOMSIX (1 << 2) /* don't use MSI-X interrupts */ +#define PCI_IRQ_NOAFFINITY (1 << 3) /* don't auto-assign affinity */ /* kmem_cache style wrapper around pci_alloc_consistent() */
Set the affinity_mask in the PCI device before allocating vectors so that the affinity can be propagated through the MSI descriptor structures to the core IRQ code. To facilitate this new __pci_enable_msi_range and __pci_enable_msix_range helpers are factored out of their not prefixed variants which assigning the new irq affinity mask in the PCI device so that the low-level interrupt code can perform the interrupt affinity assignment and do node-local allocations. A new PCI_IRQ_NOAFFINITY flag is added to pci_alloc_irq_vectors so that this function can also be used by drivers that don't wish to use the automatic affinity assignment. Signed-off-by: Christoph Hellwig <hch@lst.de> --- Documentation/PCI/MSI-HOWTO.txt | 3 + drivers/pci/msi.c | 127 ++++++++++++++++++++++++++-------------- include/linux/pci.h | 2 + 3 files changed, 89 insertions(+), 43 deletions(-)