On 1/28/21 1:37 PM, Andrew Morton wrote: > On Thu, 28 Jan 2021 06:52:21 +0100 Oscar Salvador <osalvador@xxxxxxx> wrote: > >> On Wed, Jan 27, 2021 at 03:36:41PM -0800, Mike Kravetz wrote: >>> Yes, this patch is somewhat optional. It should be a minor improvement >>> in cases where we are dealing with hpages in a non-migratable hstate. >>> Although, I do not believe this is the common case. >>> >>> The real reason for even looking into this was a comment by Oscar. With >>> the name change to HPageMigratable, it implies that the page is migratable. >>> However, this is not the case if the page's hstate does not support migration. >>> So, if we check the hstate when setting the flag we can eliminate those >>> cases where the page is certainly not migratable. >>> >>> I don't really love this patch. It has minimal functional value. >>> >>> Oscar, what do you think about dropping this? >> >> Yeah, I remember this topic arose during a discussion of patch#2 in the >> early versions, about whether the renaming to HPageMigratable made >> sense. >> >> Back then I thought that we could have this in one place at fault-path [1], >> which should have made this prettier, but it is not the case. >> True is that the optimization is little, so I am fine with dropping this >> patch. > > I've dropped it. Thanks Andrew. Michal suggested that comments describing synchronization be added for each flag. Since I did 'one patch per flag', that would be an update to each patch. Or, I could simply add a patch to update the comment block based on what you already have. Let me know what is best/easiest for you. -- Mike Kravetz
