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genirq/msi: Switch to new irq spreading infrastructure

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Switch MSI over to the new spreading code. If a pci device contains a valid
pointer to a cpumask, then this mask is used for spreading otherwise the
online cpu mask is used. This allows a driver to restrict the spread to a
subset of CPUs, e.g. cpus on a particular node.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: 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/1473862739-15032-4-git-send-email-hch@lst.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Thomas Gleixner 2016-09-14 16:18:49 +02:00
parent 34c3d9819f
commit e75eafb9b0
2 changed files with 86 additions and 71 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

126
drivers/pci/msi.c
View file

@ -549,15 +549,23 @@ static int populate_msi_sysfs(struct pci_dev *pdev)
return ret; return ret;
} }
static struct msi_desc *msi_setup_entry(struct pci_dev *dev, int nvec) static struct msi_desc *
msi_setup_entry(struct pci_dev *dev, int nvec, bool affinity)
{ {
u16 control; struct cpumask *masks = NULL;
struct msi_desc *entry; struct msi_desc *entry;
u16 control;
if (affinity) {
masks = irq_create_affinity_masks(dev->irq_affinity, nvec);
if (!masks)
pr_err("Unable to allocate affinity masks, ignoring\n");
}
/* MSI Entry Initialization */ /* MSI Entry Initialization */
entry = alloc_msi_entry(&dev->dev, nvec, NULL); entry = alloc_msi_entry(&dev->dev, nvec, masks);
if (!entry) if (!entry)
return NULL; goto out;
pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control); pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
@ -568,7 +576,6 @@ static struct msi_desc *msi_setup_entry(struct pci_dev *dev, int nvec)
entry->msi_attrib.default_irq = dev->irq; /* Save IOAPIC IRQ */ entry->msi_attrib.default_irq = dev->irq; /* Save IOAPIC IRQ */
entry->msi_attrib.multi_cap = (control & PCI_MSI_FLAGS_QMASK) >> 1; entry->msi_attrib.multi_cap = (control & PCI_MSI_FLAGS_QMASK) >> 1;
entry->msi_attrib.multiple = ilog2(__roundup_pow_of_two(nvec)); entry->msi_attrib.multiple = ilog2(__roundup_pow_of_two(nvec));
entry->affinity = dev->irq_affinity;
if (control & PCI_MSI_FLAGS_64BIT) if (control & PCI_MSI_FLAGS_64BIT)
entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_64; entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_64;
@ -579,6 +586,8 @@ static struct msi_desc *msi_setup_entry(struct pci_dev *dev, int nvec)
if (entry->msi_attrib.maskbit) if (entry->msi_attrib.maskbit)
pci_read_config_dword(dev, entry->mask_pos, &entry->masked); pci_read_config_dword(dev, entry->mask_pos, &entry->masked);
out:
kfree(masks);
return entry; return entry;
} }
@ -607,7 +616,7 @@ static int msi_verify_entries(struct pci_dev *dev)
* an error, and a positive return value indicates the number of interrupts * an error, and a positive return value indicates the number of interrupts
* which could have been allocated. * which could have been allocated.
*/ */
static int msi_capability_init(struct pci_dev *dev, int nvec) static int msi_capability_init(struct pci_dev *dev, int nvec, bool affinity)
{ {
struct msi_desc *entry; struct msi_desc *entry;
int ret; int ret;
@ -615,7 +624,7 @@ static int msi_capability_init(struct pci_dev *dev, int nvec)
pci_msi_set_enable(dev, 0); /* Disable MSI during set up */ pci_msi_set_enable(dev, 0); /* Disable MSI during set up */
entry = msi_setup_entry(dev, nvec); entry = msi_setup_entry(dev, nvec, affinity);
if (!entry) if (!entry)
return -ENOMEM; return -ENOMEM;
@ -678,28 +687,29 @@ 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, static int msix_setup_entries(struct pci_dev *dev, void __iomem *base,
struct msix_entry *entries, int nvec) struct msix_entry *entries, int nvec,
bool affinity)
{ {
const struct cpumask *mask = NULL; struct cpumask *curmsk, *masks = NULL;
struct msi_desc *entry; struct msi_desc *entry;
int cpu = -1, i; int ret, i;
for (i = 0; i < nvec; i++) { if (affinity) {
if (dev->irq_affinity) { masks = irq_create_affinity_masks(dev->irq_affinity, nvec);
cpu = cpumask_next(cpu, dev->irq_affinity); if (!masks)
if (cpu >= nr_cpu_ids) pr_err("Unable to allocate affinity masks, ignoring\n");
cpu = cpumask_first(dev->irq_affinity); }
mask = cpumask_of(cpu);
}
entry = alloc_msi_entry(&dev->dev, 1, NULL); for (i = 0, curmsk = masks; i < nvec; i++) {
entry = alloc_msi_entry(&dev->dev, 1, curmsk);
if (!entry) { if (!entry) {
if (!i) if (!i)
iounmap(base); iounmap(base);
else else
free_msi_irqs(dev); free_msi_irqs(dev);
/* No enough memory. Don't try again */ /* No enough memory. Don't try again */
return -ENOMEM; ret = -ENOMEM;
goto out;
} }
entry->msi_attrib.is_msix = 1; entry->msi_attrib.is_msix = 1;
@ -710,11 +720,14 @@ static int msix_setup_entries(struct pci_dev *dev, void __iomem *base,
entry->msi_attrib.entry_nr = i; entry->msi_attrib.entry_nr = i;
entry->msi_attrib.default_irq = dev->irq; entry->msi_attrib.default_irq = dev->irq;
entry->mask_base = base; entry->mask_base = base;
entry->affinity = mask;
list_add_tail(&entry->list, dev_to_msi_list(&dev->dev)); list_add_tail(&entry->list, dev_to_msi_list(&dev->dev));
if (masks)
curmsk++;
} }
ret = 0;
out:
kfree(masks);
return 0; return 0;
} }
@ -743,8 +756,8 @@ static void msix_program_entries(struct pci_dev *dev,
* single MSI-X irq. A return of zero indicates the successful setup of * single MSI-X irq. A return of zero indicates the successful setup of
* requested MSI-X entries with allocated irqs or non-zero for otherwise. * requested MSI-X entries with allocated irqs or non-zero for otherwise.
**/ **/
static int msix_capability_init(struct pci_dev *dev, static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries,
struct msix_entry *entries, int nvec) int nvec, bool affinity)
{ {
int ret; int ret;
u16 control; u16 control;
@ -759,7 +772,7 @@ static int msix_capability_init(struct pci_dev *dev,
if (!base) if (!base)
return -ENOMEM; return -ENOMEM;
ret = msix_setup_entries(dev, base, entries, nvec); ret = msix_setup_entries(dev, base, entries, nvec, affinity);
if (ret) if (ret)
return ret; return ret;
@ -939,22 +952,8 @@ int pci_msix_vec_count(struct pci_dev *dev)
} }
EXPORT_SYMBOL(pci_msix_vec_count); EXPORT_SYMBOL(pci_msix_vec_count);
/** static int __pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries,
* pci_enable_msix - configure device's MSI-X capability structure int nvec, bool affinity)
* @dev: pointer to the pci_dev data structure of MSI-X device function
* @entries: pointer to an array of MSI-X entries (optional)
* @nvec: number of MSI-X irqs requested for allocation by device driver
*
* Setup the MSI-X capability structure of device function with the number
* of requested irqs upon its software driver call to request for
* MSI-X mode enabled on its hardware device function. A return of zero
* indicates the successful configuration of MSI-X capability structure
* with new allocated MSI-X irqs. A return of < 0 indicates a failure.
* Or a return of > 0 indicates that driver request is exceeding the number
* of irqs or MSI-X vectors available. Driver should use the returned value to
* re-send its request.
**/
int pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, int nvec)
{ {
int nr_entries; int nr_entries;
int i, j; int i, j;
@ -986,7 +985,27 @@ int pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, int nvec)
dev_info(&dev->dev, "can't enable MSI-X (MSI IRQ already assigned)\n"); dev_info(&dev->dev, "can't enable MSI-X (MSI IRQ already assigned)\n");
return -EINVAL; return -EINVAL;
} }
return msix_capability_init(dev, entries, nvec); return msix_capability_init(dev, entries, nvec, affinity);
}
/**
* pci_enable_msix - configure device's MSI-X capability structure
* @dev: pointer to the pci_dev data structure of MSI-X device function
* @entries: pointer to an array of MSI-X entries (optional)
* @nvec: number of MSI-X irqs requested for allocation by device driver
*
* Setup the MSI-X capability structure of device function with the number
* of requested irqs upon its software driver call to request for
* MSI-X mode enabled on its hardware device function. A return of zero
* indicates the successful configuration of MSI-X capability structure
* with new allocated MSI-X irqs. A return of < 0 indicates a failure.
* Or a return of > 0 indicates that driver request is exceeding the number
* of irqs or MSI-X vectors available. Driver should use the returned value to
* re-send its request.
**/
int pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, int nvec)
{
return __pci_enable_msix(dev, entries, nvec, false);
} }
EXPORT_SYMBOL(pci_enable_msix); EXPORT_SYMBOL(pci_enable_msix);
@ -1039,6 +1058,7 @@ EXPORT_SYMBOL(pci_msi_enabled);
static 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) unsigned int flags)
{ {
bool affinity = flags & PCI_IRQ_AFFINITY;
int nvec; int nvec;
int rc; int rc;
@ -1067,19 +1087,17 @@ static int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec,
nvec = maxvec; nvec = maxvec;
for (;;) { for (;;) {
if (flags & PCI_IRQ_AFFINITY) { if (affinity) {
dev->irq_affinity = irq_create_affinity_mask(&nvec); nvec = irq_calc_affinity_vectors(dev->irq_affinity,
nvec);
if (nvec < minvec) if (nvec < minvec)
return -ENOSPC; return -ENOSPC;
} }
rc = msi_capability_init(dev, nvec); rc = msi_capability_init(dev, nvec, affinity);
if (rc == 0) if (rc == 0)
return nvec; return nvec;
kfree(dev->irq_affinity);
dev->irq_affinity = NULL;
if (rc < 0) if (rc < 0)
return rc; return rc;
if (rc < minvec) if (rc < minvec)
@ -1111,26 +1129,24 @@ static int __pci_enable_msix_range(struct pci_dev *dev,
struct msix_entry *entries, int minvec, int maxvec, struct msix_entry *entries, int minvec, int maxvec,
unsigned int flags) unsigned int flags)
{ {
int nvec = maxvec; bool affinity = flags & PCI_IRQ_AFFINITY;
int rc; int rc, nvec = maxvec;
if (maxvec < minvec) if (maxvec < minvec)
return -ERANGE; return -ERANGE;
for (;;) { for (;;) {
if (flags & PCI_IRQ_AFFINITY) { if (affinity) {
dev->irq_affinity = irq_create_affinity_mask(&nvec); nvec = irq_calc_affinity_vectors(dev->irq_affinity,
nvec);
if (nvec < minvec) if (nvec < minvec)
return -ENOSPC; return -ENOSPC;
} }
rc = pci_enable_msix(dev, entries, nvec); rc = __pci_enable_msix(dev, entries, nvec, affinity);
if (rc == 0) if (rc == 0)
return nvec; return nvec;
kfree(dev->irq_affinity);
dev->irq_affinity = NULL;
if (rc < 0) if (rc < 0)
return rc; return rc;
if (rc < minvec) if (rc < minvec)

31
kernel/irq/irqdesc.c
View file

@ -236,25 +236,24 @@ static int alloc_descs(unsigned int start, unsigned int cnt, int node,
const struct cpumask *mask = NULL; const struct cpumask *mask = NULL;
struct irq_desc *desc; struct irq_desc *desc;
unsigned int flags; unsigned int flags;
int i, cpu = -1; int i;
if (affinity && cpumask_empty(affinity)) /* Validate affinity mask(s) */
return -EINVAL; if (affinity) {
for (i = 0, mask = affinity; i < cnt; i++, mask++) {
if (cpumask_empty(mask))
return -EINVAL;
}
}
flags = affinity ? IRQD_AFFINITY_MANAGED : 0; flags = affinity ? IRQD_AFFINITY_MANAGED : 0;
mask = NULL;
for (i = 0; i < cnt; i++) { for (i = 0; i < cnt; i++) {
if (affinity) { if (affinity) {
cpu = cpumask_next(cpu, affinity); node = cpu_to_node(cpumask_first(affinity));
if (cpu >= nr_cpu_ids) mask = affinity;
cpu = cpumask_first(affinity); affinity++;
node = cpu_to_node(cpu);
/*
* For single allocations we use the caller provided
* mask otherwise we use the mask of the target cpu
*/
mask = cnt == 1 ? affinity : cpumask_of(cpu);
} }
desc = alloc_desc(start + i, node, flags, mask, owner); desc = alloc_desc(start + i, node, flags, mask, owner);
if (!desc) if (!desc)
@ -481,9 +480,9 @@ EXPORT_SYMBOL_GPL(irq_free_descs);
* @cnt: Number of consecutive irqs to allocate. * @cnt: Number of consecutive irqs to allocate.
* @node: Preferred node on which the irq descriptor should be allocated * @node: Preferred node on which the irq descriptor should be allocated
* @owner: Owning module (can be NULL) * @owner: Owning module (can be NULL)
* @affinity: Optional pointer to an affinity mask which hints where the * @affinity: Optional pointer to an affinity mask array of size @cnt which
* irq descriptors should be allocated and which default * hints where the irq descriptors should be allocated and which
* affinities to use * default affinities to use
* *
* Returns the first irq number or error code * Returns the first irq number or error code
*/ */