kstat2_md - structure for kstats metadata
#include <sys/types.h> #include <sys/kstat2.h> #include <sys/ddi.h> #include <sys/sunddi.h>
Solaris DDI specific (Solaris DDI)
To facilitate automated processing and/or display of v2 kstats, the creators of such kstats are expected to provide metadata for each value in the kstat data.
uint16_t type; /* kval semantic type */
uint16_t flags; /* per-value flags */
uint64_t scale /* Units scale */
const char *descr; /* Brief description of kval */
int8_t v1_data_type; /* Data type of the original
v1 kval */
type is the semantic type of the kstat which is set to one of the enumerated type values:
typedef enum kstat2_nv_metatype {
KSTAT2_NVMT_UNK /* Unknown type */
KSTAT2_NVMT_ID /* Arbitrary numeric or string identifier */
KSTAT2_NVMT_CNT /* Counter, example network packets */
KSTAT2_NVMT_T_EPOCH /* Time since UNIX epoch */
KSTAT2_NVMT_T_REL /* Time relative to boot time */
KSTAT2_NVMT_T_ACC /* Accumulated time */
KSTAT2_NVMT_PCT /* Percentage */
KSTAT2_NVMT_ADDR /* Memory address */
KSTAT2_NVMT_TEMP_C /* Temperature in centigrade */
KSTAT2_NVMT_RPM /* Revolutions per minute, example fan speed */
KSTAT2_NVMT_VOLT /* Voltage */
KSTAT2_NVMT_WATT /* Power usage */
KSTAT2_NVMT_CURR /* Current */
KSTAT2_NVMT_BYTES /* Bytes */
KSTAT2_NVMT_BITS /* Bits */
KSTAT2_NVMT_STATE /* Numeric or string representation of a state */
KSTAT2_NVMT_FREQ /* Frequency */
KSTAT2_NVMT_FLAGS /* Bitwise flags */
KSTAT2_NVMF_LIMIT /* Kstat's value represents limit(s) */
} kstat2_nv_metatype_t;
flags provide some additional metadata about the kval and are constructed by combining values from the enum:
typedef enum kstat2_nv_metaflag {
KSTAT2_NVMF_NONE /* No flags set */
KSTAT2_NVMF_FRACT /* Value of kval is fractional
and should be divided by scale */
KSTAT2_NVMF_IMMUT /* Value of kval will not change */
KSTAT2_NVMF_STABLE /* Kval's name and type will not
change between minor Oracle Solaris
releases */
} kstat2_nv_metaflag_t;
For example:
flags = KSTAT2_NVMF_IMMUT | KSTAT2_NVMF_STABLE;
scale is used to provide scaling information for a kval. When combined with the KSTAT2_NVMF_FRACT flag, it can be used to display or report a floating-point value whereas the actual value held in the kstat is an integer.
scale is most useful where a kval of a particular type has a large potential range. For instance, a timer might record in nanoseconds but is based in seconds. We can indicate that a timer is recording in nanoseconds by setting scale to 1x10^9 and setting the KSTAT2_NVMF_FRACT flag. Clients then know that the timer value needs to be divided by setting the scale to get the value in seconds.
v1_data_type is used to ensure that the correct data type is used for each kval when a kstat is read by a v1 client. This is for backward compatibility with existing clients. The value of this field is one of the following:
KSTAT_DATA_NONE KSTAT_DATA_CHAR KSTAT_DATA_INT32 KSTAT_DATA_UINT32 KSTAT_DATA_INT64 KSTAT_DATA_UINT64 KSTAT_DATA_LONG KSTAT_DATA_ULONG KSTAT_DATA_STRING
KSTAT1_DATA_NONE is used when the kstat or kval was not previously delivered as a v1 value. Kvals which are new in a v2 kstat converted from a v1 kstat will not be published to v1 clients.
descr is a null-terminated character string which briefly describes the kval.