Re: [linuxsh-dev] SH-4 cache performance improvement

[SUGIOKA T. <su...@it...>]

At 15:20 00/12/02 +0000, Philipp Rumpf wrote:
>On Sun, Dec 03, 2000 at 12:08:15AM +0900, SUGIOKA Toshinobu wrote:
>> current __flush_page_to_ram invalidates data cache of the page,
>> but I think write back is sufficient.  
>> 
>> I'm not sure whether this patch causes synonym problem.
>
>flush_page_to_ram implies that the page is not going to be accessed using
>the kernel mapping for a while, so a writeback should be sufficient in
>practice.  Using ocbp ratehr than ocbwb should definitely be correct and
>might be just as fast, have you tried it ?
>

I tried and found that 'ocbp' works as fast as 'ocbwb'.

According to the DaveM's documentation (Documents/cachetlb.txt)
flush_page_to_ram should write back and invalidate the D-cache.
So 'ocbp' should be correct.


----
SUGIOKA Toshinobu