ftrace: Recursion protection and speed up

This change set replaces the function tracing recursion protection with a context one, that keeps track of interrupts, NMIs, softirqs, such that we do not need to disable interrupts and not miss any events, as the old recursion protection had a race where interrupt events could be dropped.

This also speeds up function tracing by 15% or more.

I'm posting these as a generic review of the changes I'll be pushing into linux-next and will be pushing this for 3.9.

These patches have passed a series of tests I've run on few machines with several different configs and such.

You can find the patches here. I'll add these to linux-next tomorrow.

-- Steve

git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git
tip/perf/core

Head SHA1: 0b07436d95b5404134da4d661fd183eac863513e

Steven Rostedt (12):
tracing: Remove trace.h header from trace_clock.c
tracing: Fix race with max_tr and changing tracers
tracing: Fix selftest function recursion accounting
ftrace: Fix global function tracers that are not recursion safe
ftrace: Fix function tracing recursion self test
ftrace: Optimize the function tracer list loop
ftrace: Add context level recursion bit checking
tracing: Make the trace recursion bits into enums
tracing: Avoid unnecessary multiple recursion checks
ftrace: Use only the preempt version of function tracing
ring-buffer: User context bit recursion checking
ring-buffer: Remove trace.h from ring_buffer.c

----

 kernel/trace/ftrace.c          |   82 ++++++++++++++++---------
 kernel/trace/ring_buffer.c     |   88 ++++++++++++++++++--------
 kernel/trace/trace.c           |   29 ++++++---
 kernel/trace/trace.h           |  133 ++++++++++++++++++++++++++++++++++++----
 kernel/trace/trace_clock.c     |    2 -
 kernel/trace/trace_functions.c |   61 +++++-------------
 kernel/trace/trace_selftest.c  |   19 ++----
 7 files changed, 275 insertions(+), 139 deletions(-)