On Mar 12, 2007, at 11:55 PM, SODA Noriyuki wrote:

>
>>
>>>
>>>>
>>>>>
>>>>>> On Mon, 12 Mar 2007 23:28:47 -0700,
>      Jason Thorpe <thorpej@shagadelic.org> said:
>
>> There is one major difference, however.  Solaris defines "cas" as
>> COMPARE-AND-SWAP, returning the previous value of the memory cell.
>> I have defined it as COMPARE-AND- STORE, returning true if the ops
>> succeeds, or false otherwise.  The reason for this is because some
>> platforms will have extreme difficulty implementing
>> COMPARE-AND-SWAP, whereas COMPARE-AND-STORE is somewhat easier for
>> these platforms.
>
> In that case, the functions should use a different name instead of
> *_cas_*(), shouldn't they?

Oh, and dunno... m68k called it "compare-and-set" long before Solaris  
called it "compare-and-swap" :-)  Besides, the _lock_cas() we already  
have in our kernel on many platforms already uses the "cas" name for a  
compare-and-store operation.

>
> e.g.
>  *_csi_* (compare and store interlocked)?
>  *_cs_* (compare and store)?
> -- 
> soda

-- thorpej