On Fri, 19 Nov 2021, Mel Gorman wrote: > On Thu, Nov 18, 2021 at 10:22:36AM +0100, Michal Hocko wrote: > > [Cc Mel] > > > > I think this patch should be ok. There are few direct users of __GFP_HIGH > and some of them are borderline silly (e.g. mm/shmem.c specifying > __GFP_HIGH|__GFP_NOMEMALLOC) while others just look questionable ( > drivers/md/raid10.c seems to assume __GFP_HIGH guarantees allocation > success). Xen appears to be the worst abuser of __GFP_HIGH. That __GFP_HIGH in raid10.c is passed to mempool_alloc(), so there is no assumption that __GFP_HIGH will provide guarantees - the mempool does that. The comment - which I wrote 4 years ago and don't recall at all - suggest it was purely about performance - get error handling out of the way quickly. I doubt I could justify it if challenged... Thanks, NeilBrown > > -- > Mel Gorman > SUSE Labs > >
