On Wed, Jul 11, 2007 at 08:38:11PM -0700, David Miller wrote: > From: Nick Piggin <[EMAIL PROTECTED]> > Date: Thu, 12 Jul 2007 05:14:19 +0200 > > > Here is a set of patches that aims to mitigate some of the lock_page > > overhead on powerpc introduced in the fault path by another set. > > Fortunately it also improves various other things too :) > > > > After this set, a dd if=./big-sparse-file of=/dev/null on my G5 > > goes from 563MB/s to 575MB/s, or about 80ns less time per page. > > However I won't post the full set until after getting some acks > > from the arch people now, because it is a fair bit of churn in core > > code (eg. renaming !TestSetPageLocked to trylock_page). > > > > Not sure who else can take advantage of these. Sparc64 probably. > > What I would code up on sparc64 would be basically equivalent to your > generic versions. > > Or, more simply, I could just call test_and_clear_bit() et al. > directly and ignore the return value. There wouldn't be any > difference.
Oh OK, I stand corrected then. I thought you could avoid the PRE barrier on your test_and_set, and the POST barrier on test_and_clear, however I don't know exactly what sparc's barriers work. - To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
