Re: [PATCH 4/7] pci/msi: Propagate irq affinity description through the MSI code

From: Bjorn Helgaas
Date: Tue Nov 08 2016 - 16:19:05 EST

s|pci/msi|PCI/MSI| (subject)
s/irq/IRQ/ (subject)

On Mon, Nov 07, 2016 at 10:47:39AM -0800, Christoph Hellwig wrote:
> From: Christogh Hellwig <hch@xxxxxx>
>
> No API change yet, just pass it down all the way from
> pci_alloc_irq_vectors to the core MSI code.

pci_alloc_irq_vectors()

> Signed-off-by: Christogh Hellwig <hch@xxxxxx>

Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>

> ---
> drivers/pci/msi.c | 62 +++++++++++++++++++++++++++++--------------------------
> 1 file changed, 33 insertions(+), 29 deletions(-)
>
> diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
> index 1761b8a..512f388 100644
> --- a/drivers/pci/msi.c
> +++ b/drivers/pci/msi.c
> @@ -551,14 +551,14 @@ static int populate_msi_sysfs(struct pci_dev *pdev)
> }
>
> static struct msi_desc *
> -msi_setup_entry(struct pci_dev *dev, int nvec, bool affinity)
> +msi_setup_entry(struct pci_dev *dev, int nvec, const struct irq_affinity *affd)
> {
> struct cpumask *masks = NULL;
> struct msi_desc *entry;
> u16 control;
>
> - if (affinity) {
> - masks = irq_create_affinity_masks(nvec, NULL);
> + if (affd) {
> + masks = irq_create_affinity_masks(nvec, affd);
> if (!masks)
> pr_err("Unable to allocate affinity masks, ignoring\n");
> }
> @@ -618,7 +618,8 @@ static int msi_verify_entries(struct pci_dev *dev)
> * an error, and a positive return value indicates the number of interrupts
> * which could have been allocated.
> */
> -static int msi_capability_init(struct pci_dev *dev, int nvec, bool affinity)
> +static int msi_capability_init(struct pci_dev *dev, int nvec,
> + const struct irq_affinity *affd)
> {
> struct msi_desc *entry;
> int ret;
> @@ -626,7 +627,7 @@ static int msi_capability_init(struct pci_dev *dev, int nvec, bool affinity)
>
> pci_msi_set_enable(dev, 0); /* Disable MSI during set up */
>
> - entry = msi_setup_entry(dev, nvec, affinity);
> + entry = msi_setup_entry(dev, nvec, affd);
> if (!entry)
> return -ENOMEM;
>
> @@ -690,14 +691,14 @@ 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,
> - bool affinity)
> + const struct irq_affinity *affd)
> {
> struct cpumask *curmsk, *masks = NULL;
> struct msi_desc *entry;
> int ret, i;
>
> - if (affinity) {
> - masks = irq_create_affinity_masks(nvec, NULL);
> + if (affd) {
> + masks = irq_create_affinity_masks(nvec, affd);
> if (!masks)
> pr_err("Unable to allocate affinity masks, ignoring\n");
> }
> @@ -753,14 +754,14 @@ static void msix_program_entries(struct pci_dev *dev,
> * @dev: pointer to the pci_dev data structure of MSI-X device function
> * @entries: pointer to an array of struct msix_entry entries
> * @nvec: number of @entries
> - * @affinity: flag to indicate cpu irq affinity mask should be set
> + * @affd: Optional pointer to enable automatic affinity assignement
> *
> * Setup the MSI-X capability structure of device function with a
> * 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.
> **/
> static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries,
> - int nvec, bool affinity)
> + int nvec, const struct irq_affinity *affd)
> {
> int ret;
> u16 control;
> @@ -775,7 +776,7 @@ static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries,
> if (!base)
> return -ENOMEM;
>
> - ret = msix_setup_entries(dev, base, entries, nvec, affinity);
> + ret = msix_setup_entries(dev, base, entries, nvec, affd);
> if (ret)
> return ret;
>
> @@ -956,7 +957,7 @@ int pci_msix_vec_count(struct pci_dev *dev)
> EXPORT_SYMBOL(pci_msix_vec_count);
>
> static int __pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries,
> - int nvec, bool affinity)
> + int nvec, const struct irq_affinity *affd)
> {
> int nr_entries;
> int i, j;
> @@ -988,7 +989,7 @@ static int __pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries,
> dev_info(&dev->dev, "can't enable MSI-X (MSI IRQ already assigned)\n");
> return -EINVAL;
> }
> - return msix_capability_init(dev, entries, nvec, affinity);
> + return msix_capability_init(dev, entries, nvec, affd);
> }
>
> /**
> @@ -1008,7 +1009,7 @@ static int __pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries,
> **/
> int pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, int nvec)
> {
> - return __pci_enable_msix(dev, entries, nvec, false);
> + return __pci_enable_msix(dev, entries, nvec, NULL);
> }
> EXPORT_SYMBOL(pci_enable_msix);
>
> @@ -1059,9 +1060,8 @@ int pci_msi_enabled(void)
> EXPORT_SYMBOL(pci_msi_enabled);
>
> static int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec,
> - unsigned int flags)
> + const struct irq_affinity *affd)
> {
> - bool affinity = flags & PCI_IRQ_AFFINITY;
> int nvec;
> int rc;
>
> @@ -1090,13 +1090,13 @@ static int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec,
> nvec = maxvec;
>
> for (;;) {
> - if (affinity) {
> - nvec = irq_calc_affinity_vectors(nvec, NULL);
> + if (affd) {
> + nvec = irq_calc_affinity_vectors(nvec, affd);
> if (nvec < minvec)
> return -ENOSPC;
> }
>
> - rc = msi_capability_init(dev, nvec, affinity);
> + rc = msi_capability_init(dev, nvec, affd);
> if (rc == 0)
> return nvec;
>
> @@ -1123,28 +1123,27 @@ static int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec,
> **/
> int pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec)
> {
> - return __pci_enable_msi_range(dev, minvec, maxvec, 0);
> + return __pci_enable_msi_range(dev, minvec, maxvec, NULL);
> }
> 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)
> + struct msix_entry *entries, int minvec,
> + int maxvec, const struct irq_affinity *affd)
> {
> - bool affinity = flags & PCI_IRQ_AFFINITY;
> int rc, nvec = maxvec;
>
> if (maxvec < minvec)
> return -ERANGE;
>
> for (;;) {
> - if (affinity) {
> - nvec = irq_calc_affinity_vectors(nvec, NULL);
> + if (affd) {
> + nvec = irq_calc_affinity_vectors(nvec, affd);
> if (nvec < minvec)
> return -ENOSPC;
> }
>
> - rc = __pci_enable_msix(dev, entries, nvec, affinity);
> + rc = __pci_enable_msix(dev, entries, nvec, affd);
> if (rc == 0)
> return nvec;
>
> @@ -1175,7 +1174,7 @@ static int __pci_enable_msix_range(struct pci_dev *dev,
> int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries,
> int minvec, int maxvec)
> {
> - return __pci_enable_msix_range(dev, entries, minvec, maxvec, 0);
> + return __pci_enable_msix_range(dev, entries, minvec, maxvec, NULL);
> }
> EXPORT_SYMBOL(pci_enable_msix_range);
>
> @@ -1199,17 +1198,22 @@ EXPORT_SYMBOL(pci_enable_msix_range);
> int pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
> unsigned int max_vecs, unsigned int flags)
> {
> + static const struct irq_affinity msi_default_affd;
> + const struct irq_affinity *affd = NULL;
> int vecs = -ENOSPC;
>
> + if (flags & PCI_IRQ_AFFINITY)
> + affd = &msi_default_affd;
> +
> if (flags & PCI_IRQ_MSIX) {
> vecs = __pci_enable_msix_range(dev, NULL, min_vecs, max_vecs,
> - flags);
> + affd);
> if (vecs > 0)
> return vecs;
> }
>
> if (flags & PCI_IRQ_MSI) {
> - vecs = __pci_enable_msi_range(dev, min_vecs, max_vecs, flags);
> + vecs = __pci_enable_msi_range(dev, min_vecs, max_vecs, affd);
> if (vecs > 0)
> return vecs;
> }
> --
> 2.1.4
>
> --
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