Re: [PATCH v6 6/7] zsmalloc: account the number of compacted pages

[Minchan Kim <minchan@kernel.org>]

On Tue, Jul 07, 2015 at 11:21:09PM +0900, Sergey Senozhatsky wrote:
> On (07/07/15 22:39), Minchan Kim wrote:
> [..]
> > >  struct zs_pool_stats {
> > > -	/* How many objects were migrated */
> > > -	u64		num_migrated;
> > > +	/* How many pages were migrated (freed) */
> > > +	u64		pages_compacted;
> > 
> > Hmm, if we account it as page unit, unsigned long is enough for 32bit.
> 
> Well, this is a 'how many pages were freed overall' counter. We don't
> control the lifetime of device, so I think it can be bigger than 4 bytes
> in some `extreme' cases.

Technically, you're right but we have been used "unsigned long" for
seval mm stats for a long time. For exmaple, vm_event_item.
It includes many stats accumulated for the system running time.
I don't think zsmalloc is special.

> 
> 	-ss

-- 
Kind regards,
Minchan Kim

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