Michael Sundius wrote:
I know this topic has been written about but so excuse me if I am
redundant.
I saw lots of talk in the archives but I don't know if a solution was
ever arrived
at. so:
what is the current state of the use of prefetch in memcpy()? it seems that
it is #undef-ed if CONFIG_DMA_COHERENT is not turned on.
is this still because the memcpy does not check to prevent a prefetch of
addresses beyond the end of the buffer?
If so, what was the reason a solution was abandoned....
also has anyone out there written a memcopy that does use prefetch
intelligently (for mips32 that is)?
The Cavium OCTEON port overrides the default memcpy and does use
prefetch. It was recently merged (2.6.29-rc2). Look at octeon-memcpy.S
I have thought that memcpy could be generated by mm/page.c as copy_page
and clear_page are.
David Daney
