Hi Matthew, On Tue, Nov 28, 2023 at 6:09 AM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote: > > > > >From the performance perspective, kmap_local_page() does less so it > > has some performance gain. I am trying to think would it have another > > unwanted side effect of enabling interrupt and page fault while zswap > > decompressing a page. > > The decompression should not generate page fault. The interrupt > > enabling might introduce extra latency, but most of the page fault was > > having interrupt enabled anyway. The time spent in decompression is > > relatively small compared to the whole duration of the page fault. So > > the interrupt enabling during those short windows should be fine. > > "Should" is the famous last word. > > Interrupts are enabled with kmap_atomic() too. The difference is > whether we can be preempted by a higher-priority process. > You are right, thanks for the clarification. Hi Fabio, Acked-by: Chris Li <chrisl@xxxxxxxxxx> (Google) Chris
