Data Structures for Drivers kstat_io(9S)
NAME
kstat_io - structure for I/O kstats
SYNOPSIS
#include
#include
#include
#include
INTERFACE LEVEL
Solaris DDI specific (Solaris DDI)DESCRIPTION
I/O kstat statistics are kept in a kstat_io structure. When
kstat_create(9F) creates an I/O kstat, the ks_data field is
a pointer to one of these structures. The macroKSTAT_IO_PTR() is provided to retrieve this field. It looks
like this:#define KSTAT_IO_PTR(kptr) ((kstat_io_t *)(kptr)->ks_data)
STRUCTURE MEMBERSu_longlong_t nread; /* number of bytes read */
u_longlong_t nwritten; /* number of bytes written *]/
ulong_t reads; /* number of read operations */
ulong_t writes; /* number of write operations */
The nread field should be updated by the driver with the number of bytes successfully read upon completion. The nwritten field should be updated by the driver with the number of bytes successfully written upon completion. The reads field should be updated by the driver after each successful read operation. The writes field should be updated by the driver after each successful write operation.Other I/O statistics are updated through the use of the
kstat_queue(9F) functions.
SEE ALSO
SunOS 5.11 Last change: 4 Apr 1994 1
Data Structures for Drivers kstat_io(9S)
kstat_create(9F), kstat_named_init(9F), kstat_queue(9F),
kstat_runq_back_to_waitq(9F), kstat_runq_enter(9F),
kstat_runq_exit(9F), kstat_waitq_enter(9F),
kstat_waitq_exit(9F), kstat_waitq_to_runq(9F)
Writing Device DriversSunOS 5.11 Last change: 4 Apr 1994 2