Commit 8750dfe6 authored by Paul E. McKenney's avatar Paul E. McKenney
Browse files

doc: Update NMI-RCU.rst 



This commit updates NMI-RCU.rst to highlight the ancient heritage of
the example code and to discourage wanton compiler "optimizations".

Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
parent 43850011

Documentation/RCU/NMI-RCU.rst

+2 −2
Original line number Diff line number Diff line
@@ -8,7 +8,7 @@ Although RCU is usually used to protect read-mostly data structures, 
it is possible to use RCU to provide dynamic non-maskable interrupt

handlers, as well as dynamic irq handlers.  This document describes

how to do this, drawing loosely from Zwane Mwaikambo's NMI-timer

work in "arch/x86/kernel/traps.c".

work in an old version of "arch/x86/kernel/traps.c".



The relevant pieces of code are listed below, each followed by a

brief explanation::
@@ -116,7 +116,7 @@ Answer to Quick Quiz: 


	This same sad story can happen on other CPUs when using

	a compiler with aggressive pointer-value speculation

	optimizations.

	optimizations.  (But please don't!)



	More important, the rcu_dereference_sched() makes it

	clear to someone reading the code that the pointer is