ring-buffer: Use READ_ONCE() for most tail_page access
authorSteven Rostedt (Red Hat) <rostedt@goodmis.org>
Tue, 17 Nov 2015 19:03:11 +0000 (14:03 -0500)
committerSteven Rostedt <rostedt@goodmis.org>
Tue, 24 Nov 2015 14:29:15 +0000 (09:29 -0500)
commit8573636ea794fa088f459429e65e47d7776532cf
treed6d64d4272ae43e061f97c8a3c0c4aa523ed4a0e
parent3cbd6a43be932e56907abd21091314dc044175f2
ring-buffer: Use READ_ONCE() for most tail_page access

As cpu_buffer->tail_page may be modified by interrupts at almost any time,
the flow of logic is very important. Do not let gcc get smart with
re-reading cpu_buffer->tail_page by adding READ_ONCE() around most of its
accesses.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
kernel/trace/ring_buffer.c