Re: [dpdk-dev] [PATCH v5 4/5] igb_uio: use msi mask functions from kernel, little corrections

[Stephen Hemminger <stephen@networkplumber.org>]

On Thu, 31 Aug 2017 23:46:59 +0200
Markus Theil <markus.theil@tu-ilmenau.de> wrote:

> This patch substitutes the custom MSI/MSI-X mask code and uses
> already existing kernel APIs. Feedback/small corrections to the previous
> patch of this series are also incorporated.
> 
> Signed-off-by: Markus Theil <markus.theil@tu-ilmenau.de>
> ---
>  lib/librte_eal/linuxapp/igb_uio/compat.h  | 26 +++------
>  lib/librte_eal/linuxapp/igb_uio/igb_uio.c | 88 ++++++++-----------------------
>  2 files changed, 31 insertions(+), 83 deletions(-)
> 
> diff --git a/lib/librte_eal/linuxapp/igb_uio/compat.h b/lib/librte_eal/linuxapp/igb_uio/compat.h
> index 3825933..67a7ab3 100644
> --- a/lib/librte_eal/linuxapp/igb_uio/compat.h
> +++ b/lib/librte_eal/linuxapp/igb_uio/compat.h
> @@ -15,24 +15,6 @@
>  #define HAVE_PTE_MASK_PAGE_IOMAP
>  #endif
>  
> -#ifndef PCI_MSIX_ENTRY_SIZE
> -#define PCI_MSIX_ENTRY_SIZE             16
> -#define  PCI_MSIX_ENTRY_LOWER_ADDR      0
> -#define  PCI_MSIX_ENTRY_UPPER_ADDR      4
> -#define  PCI_MSIX_ENTRY_DATA            8
> -#define  PCI_MSIX_ENTRY_VECTOR_CTRL     12
> -#define   PCI_MSIX_ENTRY_CTRL_MASKBIT   1
> -#endif
> -
> -/*
> - * for kernels < 2.6.38 and backported patch that moves MSI-X entry definition
> - * to pci_regs.h Those kernels has PCI_MSIX_ENTRY_SIZE defined but not
> - * PCI_MSIX_ENTRY_CTRL_MASKBIT
> - */
> -#ifndef PCI_MSIX_ENTRY_CTRL_MASKBIT
> -#define PCI_MSIX_ENTRY_CTRL_MASKBIT    1
> -#endif
> -
>  #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 34) && \
>  	(!(defined(RHEL_RELEASE_CODE) && \
>  	 RHEL_RELEASE_CODE >= RHEL_RELEASE_VERSION(5, 9)))
> @@ -127,3 +109,11 @@ static bool pci_check_and_mask_intx(struct pci_dev *pdev)
>  #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 8, 0)
>  #define HAVE_ALLOC_IRQ_VECTORS 1
>  #endif
> +
> +#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
> +#define HAVE_PCI_MSI_MASK_IRQ 1
> +#endif
> +
> +#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 37)
> +#define HAVE_IRQ_DATA 1
> +#endif
> diff --git a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c
> index 99a085a..5830453 100644
> --- a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c
> +++ b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c
> @@ -92,51 +92,6 @@ static const struct attribute_group dev_attr_grp = {
>  	.attrs = dev_attrs,
>  };
>  
> -/*
> - * It masks the msix on/off of generating MSI-X messages.
> - */
> -static void
> -igbuio_msix_mask_irq(struct msi_desc *desc, int32_t state)
> -{
> -	u32 mask_bits = desc->masked;
> -	unsigned offset = desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
> -						PCI_MSIX_ENTRY_VECTOR_CTRL;
> -
> -	if (state != 0)
> -		mask_bits &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT;
> -	else
> -		mask_bits |= PCI_MSIX_ENTRY_CTRL_MASKBIT;
> -
> -	if (mask_bits != desc->masked) {
> -		writel(mask_bits, desc->mask_base + offset);
> -		readl(desc->mask_base);
> -		desc->masked = mask_bits;
> -	}
> -}
> -
> -/*
> - * It masks the msi on/off of generating MSI messages.
> - */
> -static void
> -igbuio_msi_mask_irq(struct pci_dev *pdev, struct msi_desc *desc, int32_t state)
> -{
> -	u32 mask_bits = desc->masked;
> -	u32 offset = desc->irq - pdev->irq;
> -	u32 mask = 1 << offset;
> -	u32 flag = !!state << offset;
> -
> -	if (!desc->msi_attrib.maskbit)
> -		return;
> -
> -	mask_bits &= ~mask;
> -	mask_bits |= flag;
> -
> -	if (mask_bits != desc->masked) {
> -		pci_write_config_dword(pdev, desc->mask_pos, mask_bits);
> -		desc->masked = mask_bits;
> -	}
> -}
> -
>  /**
>   * This is the irqcontrol callback to be registered to uio_info.
>   * It can be used to disable/enable interrupt from user space processes.
> @@ -156,31 +111,31 @@ igbuio_pci_irqcontrol(struct uio_info *info, s32 irq_state)
>  	struct rte_uio_pci_dev *udev = info->priv;
>  	struct pci_dev *pdev = udev->pdev;
>  
> -	pci_cfg_access_lock(pdev);
> -	if (udev->mode == RTE_INTR_MODE_LEGACY)
> -		pci_intx(pdev, !!irq_state);
> -
> -	else if (udev->mode == RTE_INTR_MODE_MSIX) {
> -		struct msi_desc *desc;
> -
> -#if (LINUX_VERSION_CODE < KERNEL_VERSION(4, 3, 0))
> -		list_for_each_entry(desc, &pdev->msi_list, list)
> -			igbuio_msix_mask_irq(desc, irq_state);
> +#ifdef HAVE_IRQ_DATA
> +	struct irq_data *irq = irq_get_irq_data(udev->info.irq);
>  #else
> -		list_for_each_entry(desc, &pdev->dev.msi_list, list)
> -			igbuio_msix_mask_irq(desc, irq_state);
> +	unsigned int irq = udev->info.irq;
>  #endif
> -	} else if (udev->mode == RTE_INTR_MODE_MSI) {
> -	struct msi_desc *desc;
>  
> -#if (LINUX_VERSION_CODE < KERNEL_VERSION(4, 3, 0))
> -	list_for_each_entry(desc, &pdev->msi_list, list)
> -		igbuio_msi_mask_irq(pdev, desc, irq_state);
> +	pci_cfg_access_lock(pdev);
> +
> +	if (udev->mode == RTE_INTR_MODE_MSIX || udev->mode == RTE_INTR_MODE_MSI) {
> +#ifdef HAVE_PCI_MSI_MASK_IRQ
> +		if (irq_state == 1)
> +			pci_msi_unmask_irq(irq);
> +		else
> +			pci_msi_mask_irq(irq);
>  #else
> -	list_for_each_entry(desc, &pdev->dev.msi_list, list)
> -		igbuio_msi_mask_irq(pdev, desc, irq_state);
> +		if (irq_state == 1)
> +			unmask_msi_irq(irq);
> +		else
> +			mask_msi_irq(irq);
>  #endif
>  	}
> +
> +	if (udev->mode == RTE_INTR_MODE_LEGACY)
> +		pci_intx(pdev, !!irq_state);
> +
>  	pci_cfg_access_unlock(pdev);
>  
>  	return 0;
> @@ -365,11 +320,13 @@ igbuio_pci_enable_interrupts(struct rte_uio_pci_dev *udev)
>  #else
>  		if (pci_alloc_irq_vectors(udev->pdev, 1, 1, PCI_IRQ_MSIX) == 1) {
>  			dev_dbg(&udev->pdev->dev, "using MSI-X");
> +			udev->info.irq_flags = IRQF_NO_THREAD;
>  			udev->info.irq = pci_irq_vector(udev->pdev, 0);
>  			udev->mode = RTE_INTR_MODE_MSIX;
>  			break;
>  		}
>  #endif
> +	/* fall back to MSI */
>  	case RTE_INTR_MODE_MSI:
>  #ifndef HAVE_ALLOC_IRQ_VECTORS
>  		if (pci_enable_msi(udev->pdev) == 0) {
> @@ -382,6 +339,7 @@ igbuio_pci_enable_interrupts(struct rte_uio_pci_dev *udev)
>  #else
>  		if (pci_alloc_irq_vectors(udev->pdev, 1, 1, PCI_IRQ_MSI) == 1) {
>  			dev_dbg(&udev->pdev->dev, "using MSI");
> +			udev->info.irq_flags = IRQF_NO_THREAD;
>  			udev->info.irq = pci_irq_vector(udev->pdev, 0);
>  			udev->mode = RTE_INTR_MODE_MSI;
>  			break;
> @@ -397,7 +355,7 @@ igbuio_pci_enable_interrupts(struct rte_uio_pci_dev *udev)
>  			break;
>  		}
>  		dev_notice(&udev->pdev->dev, "PCI INTX mask not supported\n");
> -		/* fall back to no IRQ */
> +	/* fall back to no IRQ */
>  	case RTE_INTR_MODE_NONE:
>  		udev->mode = RTE_INTR_MODE_NONE;
>  		udev->info.irq = 0;


Please merge patches 3 and 4. (use  git rebase -i )