Re: [patch V2 23/23] PCI/MSI: Move descriptor counting on allocation fail to the legacy code

Bjorn Helgaas
2021-12-07T21:02:51Z

On Mon, Dec 06, 2021 at 11:28:00PM +0100, Thomas Gleixner wrote:
> The irqdomain code already returns the information. Move the loop to the
> legacy code.
>
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Tested-by: Juergen Gross <jgross@suse.com>
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>

Acked-by: Bjorn Helgaas <bhelgaas@google.com>

> ---
> drivers/pci/msi/legacy.c | 20 +++++++++++++++++++-
> drivers/pci/msi/msi.c | 19 +------------------
> 2 files changed, 20 insertions(+), 19 deletions(-)
>
> --- a/drivers/pci/msi/legacy.c
> +++ b/drivers/pci/msi/legacy.c
> @@ -50,9 +50,27 @@ void __weak arch_teardown_msi_irqs(struc
> }
> }
>
> +static int pci_msi_setup_check_result(struct pci_dev *dev, int type, int ret)
> +{
> + struct msi_desc *entry;
> + int avail = 0;
> +
> + if (type != PCI_CAP_ID_MSIX || ret >= 0)
> + return ret;
> +
> + /* Scan the MSI descriptors for successfully allocated ones. */
> + for_each_pci_msi_entry(entry, dev) {
> + if (entry->irq != 0)
> + avail++;
> + }
> + return avail ? avail : ret;
> +}
> +
> int pci_msi_legacy_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
> {
> - return arch_setup_msi_irqs(dev, nvec, type);
> + int ret = arch_setup_msi_irqs(dev, nvec, type);
> +
> + return pci_msi_setup_check_result(dev, type, ret);
> }
>
> void pci_msi_legacy_teardown_msi_irqs(struct pci_dev *dev)
> --- a/drivers/pci/msi/msi.c
> +++ b/drivers/pci/msi/msi.c
> @@ -609,7 +609,7 @@ static int msix_capability_init(struct p
>
> ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX);
> if (ret)
> - goto out_avail;
> + goto out_free;
>
> /* Check if all MSI entries honor device restrictions */
> ret = msi_verify_entries(dev);
> @@ -634,23 +634,6 @@ static int msix_capability_init(struct p
> pcibios_free_irq(dev);
> return 0;
>
> -out_avail:
> - if (ret < 0) {
> - /*
> - * If we had some success, report the number of IRQs
> - * we succeeded in setting up.
> - */
> - struct msi_desc *entry;
> - int avail = 0;
> -
> - for_each_pci_msi_entry(entry, dev) {
> - if (entry->irq != 0)
> - avail++;
> - }
> - if (avail != 0)
> - ret = avail;
> - }
> -
> out_free:
> free_msi_irqs(dev);
>
>