irq
===

::

   NAME
     irq - IRQ data

   SYNOPSIS
     irq [[[index ...] | -u ] | -d | -b | -a | -s [-c cpu]]

   DESCRIPTION
     This command collaborates the data in an irq_desc_t, along with its
     associated hw_interrupt_type and irqaction structure data, into a
     consolidated per-IRQ display.  For kernel versions 2.6.37 and later
     the display consists of the irq_desc/irq_data address, its irqaction
     address(es), and the irqaction name strings.  Alternatively, the
     intel interrupt descriptor table, bottom half data, cpu affinity for
     in-use irqs, or kernel irq stats may be displayed.  If no index value
     argument(s) nor any options are entered, the IRQ data for all IRQs will
     be displayed.

       index   a valid IRQ index.
          -u   dump data for in-use IRQs only.
          -d   dump the intel interrupt descriptor table.
          -b   dump bottom half data.
          -a   dump cpu affinity for in-use IRQs.
          -s   dump the kernel irq stats; if no cpu specified with -c, the
               irq stats of all cpus will be displayed.
      -c cpu   only usable with the -s option, dump the irq stats of the 
               specified cpu[s]; cpu can be specified as "1,3,5", "1-3",
               "1,3,5-7,10", "all", or "a" (shortcut for "all").

   EXAMPLES
     Display the relevant data for IRQ 18 from a pre-2.6.37 kernel:

       crash> irq 18
           IRQ: 18
        STATUS: 0 
       HANDLER: c02301e0  <ioapic_level_irq_type>
                typename: c01f9e0c  "IO-APIC-level"
                 startup: c0110234  <unmask_IO_APIC_irq>
                shutdown: c01101cc  <mask_IO_APIC_irq>
                  handle: c0110518  <do_level_ioapic_IRQ>
                  enable: c0110234  <unmask_IO_APIC_irq>
                 disable: c01101cc  <mask_IO_APIC_irq>
        ACTION: c009c6b0
                 handler: c01ce818  <do_aic7xxx_isr>
                   flags: 4000000  (SA_SHIRQ)
                    mask: 0
                    name: c0217780  "aic7xxx"
                  dev_id: c0090078
                    next: c009c770
        ACTION: c009c770
                 handler: c01ce818  <do_aic7xxx_isr>
                   flags: 4000000  (SA_SHIRQ)
                    mask: 0
                    name: c0217780  "aic7xxx"
                  dev_id: c0091078
                    next: 0
         DEPTH: 0

     Display the relevant data for IRQ 21 from a 2.6.37 kernel:

       crash> irq 21
        IRQ   IRQ_DESC/_DATA      IRQACTION      NAME
        21   ffff88003787f780  ffff8800379a8b40  "ehci_hcd:usb2"
                               ffff8800379cbac0  "uhci_hcd:usb5"
                               ffff8800379cb140  "uhci_hcd:usb7"

     Display the intel interrupt descriptor table entries:

       crash> irq -d
         [0] divide_error
         [1] debug
         [2] nmi
         [3] int3
         [4] overflow
         [5] bounds
         [6] invalid_op
         [7] device_not_available
         [8] double_fault
         [9] coprocessor_segment_overrun
        [10] invalid_TSS
        [11] segment_not_present
        [12] stack_segment
        [13] general_protection
        [14] page_fault
        [15] spurious_interrupt_bug
        [16] coprocessor_error
        [17] alignment_check
        [18] ignore_int
        [19] ignore_int
        [20] ignore_int
        [21] ignore_int
       ...

       [250] IRQ0xda_interrupt
       [251] IRQ0xdb_interrupt
       [252] IRQ0xdc_interrupt
       [253] IRQ0xdd_interrupt
       [254] IRQ0xde_interrupt
       [255] spurious_interrupt

     Display the bottom half data:

       crash> irq -b
       SOFTIRQ_VEC      ACTION     
           [0]     ffffffff81068f60  <tasklet_hi_action> 
           [1]     ffffffff81071b80  <run_timer_softirq> 
           [2]     ffffffff813e6f30  <net_tx_action> 
           [3]     ffffffff813ee370  <net_rx_action> 
           [4]     ffffffff81211a60  <blk_done_softirq> 
           [5]     ffffffff812122f0  <blk_iopoll_softirq> 
           [6]     ffffffff81069090  <tasklet_action> 
           [7]     ffffffff81058830  <run_rebalance_domains> 
           [8]     ffffffff81087f00  <run_hrtimer_softirq> 
           [9]     ffffffff810ca7a0  <rcu_process_callbacks> 

     Display the cpu affinity for in-use IRQs:

       crash> irq -a
       IRQ NAME                 AFFINITY
         0 timer                0-23
         1 i8042                0-23
         8 rtc0                 0-23
         9 acpi                 0-23
        16 ehci_hcd:usb2,uhci_hcd:usb3,uhci_hcd:usb6 0,6,18
        17 uhci_hcd:usb4,uhci_hcd:usb7 0-23
        18 ehci_hcd:usb1,uhci_hcd:usb5,uhci_hcd:usb8,ioc0 0,11,23
        24 dmar0                0
        35 pciehp               0-23
        36 pciehp               0-23
        37 pciehp               0-23
        38 pciehp               0-23
        39 megasas              0-5,12-17
        40 lpfc:sp              0-5,12-17
        41 lpfc:fp              0,6-11,18-23
        42 lpfc:sp              0,6-11,18-23
        43 lpfc:fp              0,6-11,18-23
       ...

        80 ioat-msix            0-23
        81 ioat-msix            0-23
        82 ioat-msix            0-23
        83 ioat-msix            0-23
        84 ioat-msix            0-23
        85 ioat-msix            0-23
        86 ioat-msix            0-23
        87 ioat-msix            0-23
        88 eth4                 0,17

     Display the kernel irq stats:

       crash>irq -c 0,2 -s
                  CPU0       CPU2 
         0: 2068161471          0 IR-IO-APIC-edge     timer
         1:          9          0 IR-IO-APIC-edge     i8042
         8:          1          0 IR-IO-APIC-edge     rtc0
         9:          0          0 IR-IO-APIC-fasteoi  acpi
        16:         36          0 IR-IO-APIC-fasteoi  ehci_hcd:usb2
       ...

        85:          3          0 IR-PCI-MSI-edge     ioat-msix
        86:          3          0 IR-PCI-MSI-edge     ioat-msix
        87:          3          0 IR-PCI-MSI-edge     ioat-msix
        88:         24        295 IR-PCI-MSI-edge     eth4