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

illumos DDI specific (illumos 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

April 4, 1994 KSTAT_INTR(9S)