tracing/hw-branch-tracing: convert bts-tracer mutex to a spinlock
authorIngo Molnar <mingo@elte.hu>
Wed, 25 Feb 2009 07:40:09 +0000 (08:40 +0100)
committerIngo Molnar <mingo@elte.hu>
Wed, 25 Feb 2009 08:16:01 +0000 (09:16 +0100)
commit2d542cf34264ac92e9e7ac55c0b096b066d569d2
treee7864da3a119ba2fd1800616f0041610d09058cb
parent499aa86dcbc3c4daf7d2c59c5c30e1a78220fbc1
tracing/hw-branch-tracing: convert bts-tracer mutex to a spinlock

Impact: fix CPU hotplug lockup

bts_hotcpu_handler() is called with irqs disabled, so using mutex_lock()
is a no-no.

All the BTS codepaths here are atomic (they do not schedule), so using
a spinlock is the right solution.

Cc: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
kernel/trace/trace_hw_branches.c