On Fri, Oct 14, 2011 at 7:36 AM, Roland Dreier [off-list ref] wrote:

Anyway, suppose I have a multithreaded userspace app that uses a bunch of
pthread_mutexes, and I want to figure out which locks are hot and/or heavily
contended.  What's the best way to do that?  Is perf the right, or is there
something better?  (This seems like such an obvious thing to want that there
must be some good way to get this data, I hope)

Hi Roland,
I haven't tried this tool myself yet but have been wanting to for sometime:
http://git.0pointer.de/?p=mutrace.git

Here's the full overview of what it does:
http://0pointer.de/blog/projects/mutrace.html

Stefan