tapset::iosched(3) systemtap IO scheduler probe points

DESCRIPTION

This family of probe points is used to probe the IO scheduler activities. It contains the following probe points:

ioscheduler.elv_next_request
Fires when retrieves a request from request queue

Arguments:

elevator_name
  The elevator name

ioscheduler.elv_next_request.return
Fires when return from retrieving a request

Arguments:

req
  Address of the request

req_flags
  request flags

disk_major
  disk major number of the request

disk_minor
  disk minor number of the request

ioscheduler.elv_add_request
Fires when add a request into request queue

Arguments:

elevator_name
  The elevator name

req
  Address of the request

req_flags
  request flags

disk_major
  disk major number of the request

disk_minor
  disk minor number of the request

ioscheduler.elv_completed_request
Fires when a request is completed

Arguments:

elevator_name
  The elevator name

req
  Address of the request

req_flags
  request flags

disk_major
  disk major number of the request

disk_minor
  disk minor number of the request