On Thu, 31 Jan 2008 09:44:00 +0100 Peter Zijlstra <[EMAIL PROTECTED]> wrote:
> > On Wed, 2008-01-30 at 14:40 -0800, Andrew Morton wrote: > > On Wed, 30 Jan 2008 18:28:59 +0100 > > Peter Zijlstra <[EMAIL PROTECTED]> wrote: > > > > > Implement MADV_WILLNEED for anonymous pages by walking the page tables and > > > starting asynchonous swap cache reads for all encountered swap pages. > > > > Why cannot this use (a perhaps suitably-modified) make_pages_present()? > > Because make_pages_present() relies on page faults to bring data in and > will thus wait for all data to be present before returning. > > This solution is async; it will just issue a read for the requested > pages and moves on. > I of course realise that. I also realise that swapin_readahead() is _supposed_ to make the difference moot. There's something you guys aren't telling us. Several things, actually. Please don't do that. Implementation-wise: make_pages_present() _can_ be converted to do this. But it's a lot of patching, and the result will be a cleaner, faster and smaller core MM. Whereas your approach is easy, but adds more code and leaves the old stuff slow-and-dirty. Guess which approach is preferred? ;) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
