Re: [PATCH] pci: Display PCI IRQ pin in "info pci"

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Peter Xu (peterx@redhat.com) wrote:
> Sometimes it would be good to be able to read the pin number along
> with the IRQ number allocated.  Since we'll dump the IRQ number, no
> reason to not dump the pin information.  For example, the vfio-pci
> device will overwrite the pin with the hardware pin number.  It would
> be nice to know the pin number of one assigned device from QMP/HMP.
> 
> CC: Dr. David Alan Gilbert <dgilbert@redhat.com>
> CC: Alex Williamson <alex.williamson@redhat.com>
> CC: Michael S. Tsirkin <mst@redhat.com>
> CC: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
> CC: Julia Suvorova <jusual@redhat.com>
> CC: Markus Armbruster <armbru@redhat.com>
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
> 
> This helped me to debug an IRQ sharing issue, so may good to have it
> in master too.
> ---
>  hw/pci/pci.c       | 1 +
>  monitor/hmp-cmds.c | 3 ++-
>  qapi/misc.json     | 6 ++++--
>  3 files changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index e1ed6677e1..7ebf532ac9 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -1769,6 +1769,7 @@ static PciDeviceInfo *qmp_query_pci_device(PCIDevice *dev, PCIBus *bus,
>      info->regions = qmp_query_pci_regions(dev);
>      info->qdev_id = g_strdup(dev->qdev.id ? dev->qdev.id : "");
>  
> +    info->irq_pin = dev->config[PCI_INTERRUPT_PIN];
>      if (dev->config[PCI_INTERRUPT_PIN] != 0) {
>          info->has_irq = true;
>          info->irq = dev->config[PCI_INTERRUPT_LINE];
> diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c
> index 58724031ea..04c86bbb03 100644
> --- a/monitor/hmp-cmds.c
> +++ b/monitor/hmp-cmds.c
> @@ -680,7 +680,8 @@ static void hmp_info_pci_device(Monitor *mon, const PciDeviceInfo *dev)
>      }
>  
>      if (dev->has_irq) {
> -        monitor_printf(mon, "      IRQ %" PRId64 ".\n", dev->irq);
> +        monitor_printf(mon, "      IRQ %" PRId64 ", pin %c\n",
> +                       dev->irq, (char)('A' + dev->irq_pin - 1));

Can we trust dev->irq_pin not to be something silly and generate a
non-printable?

Dave

>      }
>  
>      if (dev->has_pci_bridge) {
> diff --git a/qapi/misc.json b/qapi/misc.json
> index c18fe681fb..f8d33ddb4e 100644
> --- a/qapi/misc.json
> +++ b/qapi/misc.json
> @@ -403,6 +403,8 @@
>  #
>  # @irq: if an IRQ is assigned to the device, the IRQ number
>  #
> +# @irq_pin: the IRQ pin, zero means no IRQ (since 5.1)
> +#
>  # @qdev_id: the device name of the PCI device
>  #
>  # @pci_bridge: if the device is a PCI bridge, the bridge information
> @@ -417,8 +419,8 @@
>  { 'struct': 'PciDeviceInfo',
>    'data': {'bus': 'int', 'slot': 'int', 'function': 'int',
>             'class_info': 'PciDeviceClass', 'id': 'PciDeviceId',
> -           '*irq': 'int', 'qdev_id': 'str', '*pci_bridge': 'PciBridgeInfo',
> -           'regions': ['PciMemoryRegion']} }
> +           '*irq': 'int', 'irq_pin': 'int', 'qdev_id': 'str',
> +           '*pci_bridge': 'PciBridgeInfo', 'regions': ['PciMemoryRegion'] }}
>  
>  ##
>  # @PciInfo:
> -- 
> 2.24.1
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK