Re: [PATCH 07/10] bootmem: add free_bootmem_late

Tejun Heo
2009-10-28T12:12:50Z

Hello,

Pekka Enberg wrote:
> On Wed, Oct 28, 2009 at 10:00 AM, Tejun Heo <tj@kernel.org> wrote:
>> ISTR an attempt to initialize the kmalloc allocator much earlier
>> during boot such that it can completely replace the bootmem allocator,
>> which would nicely remove all the complications although it may
>> require the kmalloc allocator to go through more complex boot
>> strapping steps. I didn't follow how that went. Did it prove to be
>> unworkable?
>
> We're doing it before scheduler init now but I haven't put any effort
> into moving it earlier than that yet. I don't see any fundamental
> reason we can't do that but the practical problem is that we're going
> to affect architecture specific boot code which is really hard to
> test.

Thanks for the explanation. It would be really great if we can pull
that off someday. This should be doable architecture-by-architecture,
right? You can, for example, first convert x86 and then make bootmem
allocator thin wrapper around the slab allocator. After all archs
have been converted, the wrappers can be dropped.

--
tejun