On Tue, Apr 23, 2024 at 01:27:09PM +0200, Thomas Zimmermann wrote: > Am 23.04.24 um 11:55 schrieb Nam Cao: ... > > > The page-fault handler at [1] use vm_fault.pgoff to retrieve the page > > > structure. Can we do the same here and avoid that computation? > > Yes, thanks for the suggestion. > > > > It will change things a bit: offset will not be the exact value anymore, > > but will be rounded down to multiple of PAGE_SIZE. But that doesn't matter, > > because it will only be used to calculate the page offset later on. > > > > We can clean this up and rename this "offset" to "pg_offset". But that's > > for another day. > > But can't we use struct vm_fault.pgoff directly? The page-fault handler has > used it since forever. The look-up code for the pageref should probably do > the same, because there's a 1:1 connection between the page and the pageref. > The pageref structure only exists because we cannot store its data in struct > page directly. > > AFAICT pgoff is exactly the value want to compute. See [1] and the > calculation at [2]. Completely agree. I just wanted to point out that the value inside the variable "offset" won't be the same as before, but it's still correct. I just tested the patch on real hardware, will send it shortly. Best regards, Nam
