zfsonlinux/spl — pull request #288 by prakashsurya (2013-09-11 16:12:13+00:00)
Title: Add new kstat KSTAT_TYPE_READ type

Add a new kstat type for tracking useful statistics about read.
The new KSTAT_TYPE_READ type can be used to track the following
statistics for each read:

* A unique identifier (uint64_t)
* The time the entry was added to the list (hrtime_t)
(*not* wall clock time; relative to the other entries on the list)
* The objset ID (uint64_t)
* The object number (uint64_t)
* The indirection level (uint64_t)
* The block ID (uint64_t)
* The name of the function originating the arc_read call (char[24])
* The arc_flags from the arc_read call (uint32_t)

Signed-off-by: Prakash Surya