Re: [PATCH] zsmalloc: fix linking bug in init_zspage

From: Sergey Senozhatsky
Date: Tue Aug 14 2018 - 09:27:04 EST


Hi Minchan,

On (08/14/18 09:24), Minchan Kim wrote:
> > Any thoughts?
>
> If we want a refactoring, I'm not against but description said it tiggered
> BUG_ON on zs_map_object rarely. That means it should be stable material
> and need more description to understand. Please be more specific with
> some example.

I don't have any BUG_ON on hands. Would be great if zhouxianrong could
post some backtraces or more info/explanation.

> The reason I'm hesitating is zsmalloc moves ZS_FULL group
> when the zspage->inuse is equal to class->objs_per_zspage so I thought
> it shouldn't allocate last partial object.

Maybe, allocating last partial object does look a bit hacky - it's not a
valid object anyway, but I'm not suggesting that we need to change it.
Let's hear from zhouxianrong.

-ss