| Message ID | 20221111122015.574339988@linutronix.de (mailing list archive) |
|---|---|
| State | Handled Elsewhere |
| Headers | show |
| Series | genirq, PCI/MSI: Support for per device MSI and PCI/IMS - Part 1 cleanups | expand |
On Fri, Nov 11, 2022 at 02:55:09PM +0100, Thomas Gleixner wrote: > When hierarchical MSI interrupt domains are enabled then there is no point > to do tons of work and detect the missing support for multi-MSI late in the > allocation path. > > Just query the domain feature flags right away. The query function is going > to be used for other purposes later and has a mode argument which influences > the result: > > ALLOW_LEGACY returns true when: > - there is no irq domain attached (legacy support) > - there is a irq domain attached which has the feature flag set > > DENY_LEGACY returns only true when: > - there is a irq domain attached which has the feature flag set > > This allows to use the function universally without ifdeffery in the > calling code. > > Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Bjorn Helgaas <bhelgaas@google.com> > --- > drivers/pci/msi/irqdomain.c | 22 ++++++++++++++++++++++ > drivers/pci/msi/msi.c | 4 ++++ > drivers/pci/msi/msi.h | 9 +++++++++ > 3 files changed, 35 insertions(+) > > --- a/drivers/pci/msi/irqdomain.c > +++ b/drivers/pci/msi/irqdomain.c > @@ -187,6 +187,28 @@ struct irq_domain *pci_msi_create_irq_do > } > EXPORT_SYMBOL_GPL(pci_msi_create_irq_domain); > > +/** > + * pci_msi_domain_supports - Check for support of a particular feature flag > + * @pdev: The PCI device to operate on > + * @feature_mask: The feature mask to check for (full match) > + * @mode: If ALLOW_LEGACY this grants the feature when there is no irq domain > + * associated to the device. If DENY_LEGACY the lack of an irq domain > + * makes the feature unsupported Looks like some of these might be wider than 80 columns, which I think was the typical width of this file. > + */ > +bool pci_msi_domain_supports(struct pci_dev *pdev, unsigned int feature_mask, > + enum support_mode mode) > +{ > + struct msi_domain_info *info; > + struct irq_domain *domain; > + > + domain = dev_get_msi_domain(&pdev->dev); > + > + if (!domain || !irq_domain_is_hierarchy(domain)) > + return mode == ALLOW_LEGACY; > + info = domain->host_data; > + return (info->flags & feature_mask) == feature_mask; > +} > + > /* > * Users of the generic MSI infrastructure expect a device to have a single ID, > * so with DMA aliases we have to pick the least-worst compromise. Devices with > --- a/drivers/pci/msi/msi.c > +++ b/drivers/pci/msi/msi.c > @@ -347,6 +347,10 @@ static int msi_capability_init(struct pc > struct msi_desc *entry; > int ret; > > + /* Reject multi-MSI early on irq domain enabled architectures */ > + if (nvec > 1 && !pci_msi_domain_supports(dev, MSI_FLAG_MULTI_PCI_MSI, ALLOW_LEGACY)) > + return 1; > + > /* > * Disable MSI during setup in the hardware, but mark it enabled > * so that setup code can evaluate it. > --- a/drivers/pci/msi/msi.h > +++ b/drivers/pci/msi/msi.h > @@ -97,6 +97,15 @@ int __pci_enable_msix_range(struct pci_d > void __pci_restore_msi_state(struct pci_dev *dev); > void __pci_restore_msix_state(struct pci_dev *dev); > > +/* irq_domain related functionality */ > + > +enum support_mode { > + ALLOW_LEGACY, > + DENY_LEGACY, > +}; > + > +bool pci_msi_domain_supports(struct pci_dev *dev, unsigned int feature_mask, enum support_mode mode); > + > /* Legacy (!IRQDOMAIN) fallbacks */ > > #ifdef CONFIG_PCI_MSI_ARCH_FALLBACKS >
On Fri, Nov 11, 2022 at 02:55:09PM +0100, Thomas Gleixner wrote: > When hierarchical MSI interrupt domains are enabled then there is no point > to do tons of work and detect the missing support for multi-MSI late in the > allocation path. > > Just query the domain feature flags right away. The query function is going > to be used for other purposes later and has a mode argument which influences > the result: > > ALLOW_LEGACY returns true when: > - there is no irq domain attached (legacy support) > - there is a irq domain attached which has the feature flag set > > DENY_LEGACY returns only true when: > - there is a irq domain attached which has the feature flag set > > This allows to use the function universally without ifdeffery in the > calling code. > > Signed-off-by: Thomas Gleixner <tglx@linutronix.de> > --- > drivers/pci/msi/irqdomain.c | 22 ++++++++++++++++++++++ > drivers/pci/msi/msi.c | 4 ++++ > drivers/pci/msi/msi.h | 9 +++++++++ > 3 files changed, 35 insertions(+) Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Jason
On Wed, Nov 16 2022 at 10:31, Bjorn Helgaas wrote: > On Fri, Nov 11, 2022 at 02:55:09PM +0100, Thomas Gleixner wrote: >> >> +/** >> + * pci_msi_domain_supports - Check for support of a particular feature flag >> + * @pdev: The PCI device to operate on >> + * @feature_mask: The feature mask to check for (full match) >> + * @mode: If ALLOW_LEGACY this grants the feature when there is no irq domain >> + * associated to the device. If DENY_LEGACY the lack of an irq domain >> + * makes the feature unsupported > > Looks like some of these might be wider than 80 columns, which I think > was the typical width of this file. I accommodated to the general sentiment that 80 columns is yesterday. My new cutoff is 100. Thanks, tglx
--- a/drivers/pci/msi/irqdomain.c +++ b/drivers/pci/msi/irqdomain.c @@ -187,6 +187,28 @@ struct irq_domain *pci_msi_create_irq_do } EXPORT_SYMBOL_GPL(pci_msi_create_irq_domain); +/** + * pci_msi_domain_supports - Check for support of a particular feature flag + * @pdev: The PCI device to operate on + * @feature_mask: The feature mask to check for (full match) + * @mode: If ALLOW_LEGACY this grants the feature when there is no irq domain + * associated to the device. If DENY_LEGACY the lack of an irq domain + * makes the feature unsupported + */ +bool pci_msi_domain_supports(struct pci_dev *pdev, unsigned int feature_mask, + enum support_mode mode) +{ + struct msi_domain_info *info; + struct irq_domain *domain; + + domain = dev_get_msi_domain(&pdev->dev); + + if (!domain || !irq_domain_is_hierarchy(domain)) + return mode == ALLOW_LEGACY; + info = domain->host_data; + return (info->flags & feature_mask) == feature_mask; +} + /* * Users of the generic MSI infrastructure expect a device to have a single ID, * so with DMA aliases we have to pick the least-worst compromise. Devices with --- a/drivers/pci/msi/msi.c +++ b/drivers/pci/msi/msi.c @@ -347,6 +347,10 @@ static int msi_capability_init(struct pc struct msi_desc *entry; int ret; + /* Reject multi-MSI early on irq domain enabled architectures */ + if (nvec > 1 && !pci_msi_domain_supports(dev, MSI_FLAG_MULTI_PCI_MSI, ALLOW_LEGACY)) + return 1; + /* * Disable MSI during setup in the hardware, but mark it enabled * so that setup code can evaluate it. --- a/drivers/pci/msi/msi.h +++ b/drivers/pci/msi/msi.h @@ -97,6 +97,15 @@ int __pci_enable_msix_range(struct pci_d void __pci_restore_msi_state(struct pci_dev *dev); void __pci_restore_msix_state(struct pci_dev *dev); +/* irq_domain related functionality */ + +enum support_mode { + ALLOW_LEGACY, + DENY_LEGACY, +}; + +bool pci_msi_domain_supports(struct pci_dev *dev, unsigned int feature_mask, enum support_mode mode); + /* Legacy (!IRQDOMAIN) fallbacks */ #ifdef CONFIG_PCI_MSI_ARCH_FALLBACKS
When hierarchical MSI interrupt domains are enabled then there is no point to do tons of work and detect the missing support for multi-MSI late in the allocation path. Just query the domain feature flags right away. The query function is going to be used for other purposes later and has a mode argument which influences the result: ALLOW_LEGACY returns true when: - there is no irq domain attached (legacy support) - there is a irq domain attached which has the feature flag set DENY_LEGACY returns only true when: - there is a irq domain attached which has the feature flag set This allows to use the function universally without ifdeffery in the calling code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> --- drivers/pci/msi/irqdomain.c | 22 ++++++++++++++++++++++ drivers/pci/msi/msi.c | 4 ++++ drivers/pci/msi/msi.h | 9 +++++++++ 3 files changed, 35 insertions(+)