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)