KS_UPDATE(9E) | Driver Entry Points | KS_UPDATE(9E) |
#include <sys/types.h> #include <sys/kstat.h> #include <sys/ddi.h> #include <sys/sunddi.h> int prefix_ks_update(kstat_t *ksp, int rw);
rw
KSTAT_READ
KSTAT_WRITE
The ks_update() function must have the following structure:
static int xx_kstat_update(kstat_t *ksp, int rw) { if (rw == KSTAT_WRITE) { /* update the native stats from ksp->ks_data */ /* return EACCES if you don't support this */ } else { /* update ksp->ks_data from the native stats */ } return (0); }
In general, the ks_update() routine may need to refer to provider-private data; for example, it may need a pointer to the provider's raw statistics. The ks_private field is available for this purpose. Its use is entirely at the provider's discretion.
No kstat locking should be done inside the ks_update() routine. The caller will already be holding the kstat's ks_lock (to ensure consistent data) and will prevent the kstat from being removed.
0
EACCES
EIO
Writing Device Drivers
May 27, 1994 | OmniOS |