STRUCT CMBDATA(9) The ccw bus STRUCT CMBDATA(9)NAMEstruct_cmbdata - channel measurement block data for user space
SYNOPSIS
struct cmbdata {
__u64 size;
__u64 elapsed_time;
__u64 ssch_rsch_count;
__u64 sample_count;
__u64 device_connect_time;
__u64 function_pending_time;
__u64 device_disconnect_time;
__u64 control_unit_queuing_time;
__u64 device_active_only_time;
__u64 device_busy_time;
__u64 initial_command_response_time;
};
MEMBERS
size
size of the stored data
elapsed_time
time since last sampling
ssch_rsch_count
number of ssch and rsch
sample_count
number of samples
device_connect_time
time of device connect
function_pending_time
time of function pending
device_disconnect_time
time of device disconnect
control_unit_queuing_time
time of control unit queuing
device_active_only_time
time of device active only
device_busy_time
time of device busy (ext. format)
initial_command_response_time
initial command response time (ext. format)
DESCRIPTION
All values are stored as 64 bit for simplicity, especially in 32 bit
emulation mode. All time values are normalized to nanoseconds.
Currently, two formats are known, which differ by the size of this
structure, i.e. the last two members are only set when the extended
channel measurement facility (first shipped in z990 machines) is
activated. Potentially, more fields could be added, which would result
in a new ioctl number.
AUTHOR
Cornelia Huck <cornelia.huck@de.ibm.com>
Author.
COPYRIGHTKernel Hackers Manual 2.6. November 2013 STRUCT CMBDATA(9)
