On Wed, Mar 16, 2022 at 06:39:28AM +0000, cgel.zte@xxxxxxxxx wrote: > From: Yang Yang <yang.yang29@xxxxxxxxxx> > > psi tracks the time spent on submitting the IO of refaulting file pages > and anonymous pages[1]. But after we tracks refaulting anonymous pages > in swap_readpage[2][3], there is no need to track refaulting anonymous > pages in submit_bio. > > So this patch can reduce redundant calling of psi_memstall_enter. And > make it easier to track refaulting file pages and anonymous pages > separately. I don't think this is an improvement. psi_memstall_enter() will check current->in_memstall once, detect the nested call, and bail. Your patch checks PageSwapBacked for every page being added. It's more branches for less robust code.
