On Thu, Apr 20, 2017 at 10:45:42AM +0900, Sergey Senozhatsky wrote: > On (04/19/17 04:51), Matthew Wilcox wrote: > [..] > > > > > Another approach is the API does normal thing for non-aligned prefix > > > > > and > > > > > tail space and fast thing for aligned space. > > > > > Otherwise, it would be happy if the API has WARN_ON non-page SIZE > > > > > aligned > > > > > address. > > > > Why not just use memcpy()? Is copy_page() significantly faster than > > memcpy() for a PAGE_SIZE amount of data? > > that's a good point. > > I was going to ask yesterday - do we even need copy_page()? arch that > provides well optimized copy_page() quite likely provides somewhat > equally optimized memcpy(). so may be copy_page() is not even needed?
I don't know. Just I found https://download.samba.org/pub/paulus/ols-2003-presentation.pdf and heard https://lkml.org/lkml/2017/4/10/1270.
