[PATCH] Add PTHREAD_MUTEX_NORMAL_INT

[Andi Kleen]

> > commit 61dd6208fb1e59a423b6dfa712a3c896c34b2590
> > Author: Siddhesh Poyarekar <siddhesh@redhat.com>
> > Date:   Sat Jun 15 12:24:15 2013 +0530
> > 
> >     New API to set default thread attributes
> > 
> > Why are any additions I make suddenly such a big problem?
> 
> A new API is very different from a new ABI version of an existing API.

The patches to implement the new version of gettype / the new NORMAL
is already separate.  Also if it's really a problem we can drop it
and just do what the original patches did.

The other patches don't add any new versions, just two new bits
to two existing APIs (enable/disable elision for mutexes and
rwlocks respectively)

Also all of these patches have been already reviewed by multiple
people, including Carlos.


> Also, the tuning per-lock is not nearly as impactful as adding mutex
> type constants or changing the meaning of existing ones in subtle
> ways. Adding these new tuning functions will not affect any
> application that does not use them, i.e. any current application and
> any conforming POSIX application. On the other hand, changing NORMAL
> will affect many applications.

FWIW i spent quite some time on debian codesearch and koders.com 
and I determined that NORMAL or pthread_mutexattr_settype(DEFAULT)
is not widely used at all. That was the only reason I agreed to
disable elision for NORMAL and plain settype() on old binaries.

-Andi