On Mon, Aug 26, 2024 at 4:53 PM Michal Hocko <mho...@kernel.org> wrote: > > From: Michal Hocko <mho...@suse.com> > > There is no existing user of the flag and the flag is dangerous because > a nested allocation context can use GFP_NOFAIL which could cause > unexpected failure. Such a code would be hard to maintain because it > could be deeper in the call chain. > > PF_MEMALLOC_NORECLAIM has been added even when it was pointed out [1] > that such a allocation contex is inherently unsafe if the context > doesn't fully control all allocations called from this context. > > [1] https://lore.kernel.org/all/ZcM0xtlKbAOFjv5n@tiehlicka/ > > Signed-off-by: Michal Hocko <mho...@suse.com> > --- > include/linux/sched.h | 1 - > include/linux/sched/mm.h | 7 ++----- > 2 files changed, 2 insertions(+), 6 deletions(-) > > diff --git a/include/linux/sched.h b/include/linux/sched.h > index f8d150343d42..72dad3a6317a 100644 > --- a/include/linux/sched.h > +++ b/include/linux/sched.h > @@ -1657,7 +1657,6 @@ extern struct pid *cad_pid; > * I am cleaning dirty pages > from some other bdi. */ > #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ > #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address > space */ > -#define PF_MEMALLOC_NORECLAIM 0x00800000 /* All allocation requests > will clear __GFP_DIRECT_RECLAIM */
To maintain consistency with the other unused bits, it would be better to define PF__HOLE__00800000 instead. -- Regards Yafang