|| ||Peter Zijlstra <email@example.com>|
Andrew Morton <firstname.lastname@example.org>|
|| ||[PATCH 0/5] lock contention tracking -v3|
|| ||Tue, 29 May 2007 14:52:48 +0200|
|| ||Ingo Molnar <email@example.com>, Bill Huey <firstname.lastname@example.org>,
Jason Baron <email@example.com>,
Steven Rostedt <firstname.lastname@example.org>,
Christoph Hellwig <email@example.com>,
Peter Zijlstra <firstname.lastname@example.org>|
Use the lockdep infrastructure to track lock contention and other lock
It tracks lock contention events, and the first four unique call-sites that
It also measures lock wait-time and hold-time in nanoseconds. The minimum and
maximum times are tracked, as well as a total (which together with the number
of event can give the avg).
All statistics are done per lock class, per write (exclusive state) and per read
The statistics are collected per-cpu, so that the collection overhead is
minimized via having no global cachemisses.
This new lock statistics feature is independent of the lock dependency checking
traditionally done by lockdep; it just shares the lock tracking code. It is
also possible to enable both and runtime disabled either component - thereby
avoiding the O(n^2) lock chain walks for instance.
Andrew, can we give this a spin in -mm?