On Thu, Feb 10, 2022 at 02:25:01PM -0800, Shakeel Butt wrote:
> On Thu, Feb 10, 2022 at 12:03 PM Roman Gushchin <guro@xxxxxx> wrote:
> >
> > On Thu, Feb 10, 2022 at 12:14:35AM -0800, Shakeel Butt wrote:
> > > Currently the kernel force charges the allocations which have __GFP_HIGH
> > > flag without triggering the memory reclaim. __GFP_HIGH indicates that
> > > the caller is high priority and since commit 869712fd3de5 ("mm:
> > > memcontrol: fix network errors from failing __GFP_ATOMIC charges") the
> > > kernel let such allocations do force charging. Please note that
> > > __GFP_ATOMIC has been replaced by __GFP_HIGH.
> > >
> > > __GFP_HIGH does not tell if the caller can block or can trigger reclaim.
> > > There are separate checks to determine that. So, there is no need to
> > > skip reclaim for __GFP_HIGH allocations. So, handle __GFP_HIGH together
> > > with __GFP_NOFAIL which also does force charging.
> >
> > This sounds very reasonable. But shouldn't we check if __GFP_DIRECT_RECLAIM
> > is set and bail out otherwise?
> >
>
> We already have a gfpflags_allow_blocking() check which checks for
> __GFP_DIRECT_RECLAIM.
Indeed. Please, feel free to add
Reviewed-by: Roman Gushchin <guro@xxxxxx> to the patch.
Thank you!
