tracing: Remove locking trace_types_lock from tracing_reset_all_online_cpus()
tracing: Remove locking trace_types_lock from tracing_reset_all_online_cpus()

Commit a82274151af "tracing: Protect ftrace_trace_arrays list in trace_events.c"
added taking the trace_types_lock mutex in trace_events.c as there were
several locations that needed it for protection. Unfortunately, it also
encapsulated a call to tracing_reset_all_online_cpus() which also takes
the trace_types_lock, causing a deadlock.

This happens when a module has tracepoints and has been traced. When the
module is removed, the trace events module notifier will grab the
trace_types_lock, do a bunch of clean ups, and also clears the buffer
by calling tracing_reset_all_online_cpus. This doesn't happen often
which explains why it wasn't caught right away.

Commit a82274151af was marked for stable, which means this must be
sent to stable too.

Link: http://lkml.kernel.org/r/51EEC646.7070306@broadcom.com

Reported-by: Arend van Spril <06447fbe43693466d3293d0b5eaeeb2efd3d7d3a@broadcom.com>
Tested-by: Arend van Spriel <06447fbe43693466d3293d0b5eaeeb2efd3d7d3a@broadcom.com>
Cc: Alexander Z Lam <03fca28f4feea1a7d93654bea20660d7306832b4@google.com>
Cc: Vaibhav Nagarnaik <1fa667586c90bce718fd3c486c1144f98789d483@google.com>
Cc: David Sharp <d17c0a8430b0bd65a7a6ae309f7a3dc190d92668@google.com>
Cc: 4fbacc2fa0ffdbb11bf1ad6925b886ebd08dd15f@vger.kernel.org # 3.10
Signed-off-by: Steven Rostedt <43232e92d70cc7aa53504ad0397085ee47bad87f@goodmis.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs