sched_clock()

링크 : http://lwn.net/Articles/396616/
링크 : http://marc.info/?l=linux-kernel&m=127474630527689&w=2

Finer granularity and task/cgroup irq time accounting

에 대한글을 먼저 읽고.



출처 :  http://lwn.net/Articles/335653/

sched: sched_clock() clocksource handling.

There are presently a number of issues and limitations with how the
clocksource and sched_clock() interaction works today. Configurations
tend to be grouped in to one of the following:

    - Platform provides a clocksource unsuitable for sched_clock()
      and prefers to use the generic jiffies-backed implementation.

    - Platform provides its own clocksource and sched_clock() that
      wraps in to it.

    - Platform uses a generic clocksource (ie, drivers/clocksource/)
      combined with the generic jiffies-backed sched_clock().

    - Platform supports multiple sched_clock()-capable clocksources.