kstat_intr(9S)						    Data Structures for Drivers 					    kstat_intr(9S)

NAME

       kstat_intr - structure for interrupt kstats

SYNOPSIS

       #include <sys/types.h>
       #include <sys/kstat.h>
       #include <sys/ddi.h>
       #include <sys/sunddi.h>

INTERFACE LEVEL

       Solaris DDI specific (Solaris DDI)

DESCRIPTION

       Interrupt statistics are kept in the kstat_intr structure. When kstat_create(9F) creates an interrupt kstat, the ks_data field is a pointer
       to one of these structures. The macro KSTAT_INTR_PTR() is provided to retrieve this field. It looks like this:

       #define KSTAT_INTR_PTR(kptr)  ((kstat_intr_t *)(kptr)->ks_data)

       An interrupt is a hard interrupt (sourced from the hardware device itself), a soft interrupt (induced by the system through the use of some
       system interrupt source), a watchdog interrupt (induced by a periodic timer call), spurious (an interrupt entry point was entered but there
       was no interrupt to service), or multiple service (an interrupt was detected and serviced just prior to returning from  any  of	the  other
       types).

       Drivers	generally  report  only  claimed hard interrupts and soft interrupts from their handlers, but measurement of the spurious class of
       interrupts is useful for auto-vectored devices in order to pinpoint any interrupt latency problems in a particular system configuration.

       Devices that have more than one interrupt of the same type should use multiple structures.

STRUCTURE MEMBERS

       ulong_t	  intrs[KSTAT_NUM_INTRS];    /* interrupt counters */

       The only member exposed to drivers is the intrs member. This field is an array of counters. The driver must use the appropriate counter	in
       the array based on the type of interrupt condition.

       The following indexes are supported:

       KSTAT_INTR_HARD

	   Hard interrupt

       KSTAT_INTR_SOFT

	   Soft interrupt

       KSTAT_INTR_WATCHDOG

	   Watchdog interrupt

       KSTAT_INTR_SPURIOUS

	   Spurious interrupt

       KSTAT_INTR_MULTSVC

	   Multiple service interrupt

SEE ALSO

       kstat(9S)

       Writing Device Drivers

SunOS 5.10							    4 Apr 1994							    kstat_intr(9S)