Re: [PATCH v4 54/66] mm/memcontrol: Stop using mm->highest_vm_end

[Liam Howlett]

* Vlastimil Babka <vbabka@xxxxxxx> [220120 06:21]:
> On 12/1/21 15:30, Liam Howlett wrote:
> > From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>
> > 
> > Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
> > ---
> >  mm/memcontrol.c | 6 ++----
> >  1 file changed, 2 insertions(+), 4 deletions(-)
> > 
> > diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> > index 781605e92015..ac95b3eca557 100644
> > --- a/mm/memcontrol.c
> > +++ b/mm/memcontrol.c
> > @@ -5808,7 +5808,7 @@ static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm)
> >  	unsigned long precharge;
> >  
> >  	mmap_read_lock(mm);
> > -	walk_page_range(mm, 0, mm->highest_vm_end, &precharge_walk_ops, NULL);
> > +	walk_page_range(mm, 0, -1, &precharge_walk_ops, NULL);
> 
> Wouldn't ULONG_MAX look better?

Sure, I'm happy enough to use ULONG_MAX.

> 
> >  	mmap_read_unlock(mm);
> >  
> >  	precharge = mc.precharge;
> > @@ -6106,9 +6106,7 @@ static void mem_cgroup_move_charge(void)
> >  	 * When we have consumed all precharges and failed in doing
> >  	 * additional charge, the page walk just aborts.
> >  	 */
> > -	walk_page_range(mc.mm, 0, mc.mm->highest_vm_end, &charge_walk_ops,
> > -			NULL);
> > -
> > +	walk_page_range(mc.mm, 0, -1, &charge_walk_ops, NULL);
> >  	mmap_read_unlock(mc.mm);
> >  	atomic_dec(&mc.from->moving_account);
> >  }
>