Poul-Henning Kamp 7194d335cf Run a revision of the devstat interface: ... Kernel: Change statistics to use the *uptime() timescale (ie: relative to boottime) rather than the UTC aligned timescale. This makes the device statistics code oblivious to clock steps. Change timestamps to bintime format, they are cheaper. Remove the "busy_count", and replace it with two counter fields: "start_count" and "end_count", which are updated in the down and up paths respectively. This removes the locking constraint on devstat. Add a timestamp argument to devstat_start_transaction(), this will normally be a timestamp set by the *_bio() function in bp->bio_t0. Use this field to calculate duration of I/O operations. Add two timestamp arguments to devstat_end_transaction(), one is the current time, a NULL pointer means "take timestamp yourself", the other is the timestamp of when this transaction started (see above). Change calculation of busy_time to operate on "the salami principle": Only when we are idle, which we can determine by the start+end counts being identical, do we update the "busy_from" field in the down path. In the up path we accumulate the timeslice in busy_time and update busy_from. Change the byte_* and num_* fields into two arrays: bytes[] and operations[]. Userland: Change the misleading "busy_time" name to be called "snap_time" and make the time long double since that is what most users need anyway, fill it using clock_gettime(CLOCK_MONOTONIC) to put it on the same timescale as the kernel fields. Change devstat_compute_etime() to operate on struct bintime. Remove the version 2 legacy interface: the change to bintime makes compatibility far too expensive. Fix a bug in systat's "vm" page where boot relative busy times would be bogus. Bump __FreeBSD_version to 500107 Review & Collaboration by: ken		2003-03-15 21:59:06 +00:00
..
scsi	Don't use the devstat->busy_count for state decisions in the device	2003-03-15 11:00:56 +00:00
cam_ccb.h
cam_debug.h
cam_periph.c	Run a revision of the devstat interface:	2003-03-15 21:59:06 +00:00
cam_periph.h	Centralize the devstat handling for all GEOM disk device drivers	2003-03-08 08:01:31 +00:00
cam_queue.c	Fix typos, mostly s/ an / a / where appropriate and a few s/an/and/	2002-12-30 21:18:15 +00:00
cam_queue.h
cam_sim.c	Back out M_* changes, per decision of the TRB.	2003-02-19 05:47:46 +00:00
cam_sim.h
cam_xpt_periph.h
cam_xpt_sim.h
cam_xpt.c	Centralize the devstat handling for all GEOM disk device drivers	2003-03-08 08:01:31 +00:00
cam_xpt.h
cam.c
cam.h