On Fri, 1 Feb 2002, Hiroyuki Machida wrote:

quoted

It will fail if *p is not same as oldval.

Please note that "sc" may fail even if nobody write the
variable. (See P.211 "8.4.2 Load-Linked/Sotre-Conditional" of "See 
MIPS RUN" for more detail.) 
So, after your patch applied, compare_and_swap() may fail, even if
*p is equal to oldval.

 That's exactly what I meant -- "sc" may fail to execute the store, while
"cmpxchgl" may not. 

-- 
+  Maciej W. Rozycki, Technical University of Gdansk, Poland   +
+--------------------------------------------------------------+
+        e-mail: macro@ds2.pg.gda.pl, PGP key available        +