Subject: Re: Extensible malloc types
To: Jason R Thorpe <thorpej@wasabisystems.com>
From: Alistair Crooks <agc@wasabisystems.com>
List: tech-kern
Date: 01/31/2003 10:16:30
On Thu, Jan 30, 2003 at 09:38:26PM -0800, Jason R Thorpe wrote:
> Folks...
>
> I have integrated the extensible malloc type framework from FreeBSD. For
> those not familiar with it, it removes the central location of malloc type
> definitions, instead allowing each subsystem to define its own malloc types.
>
> Uses of the kernel malloc API don't really see any difference, however
> things that pass malloc types around now must use "struct malloc_type *"
> instead of "int" (this meant fixing up audio drivers, which was by far
> the most invasive part of these changes).
>
> Among other things, this mechanism is more LKM-friendly, and also makes
> it easier for 3rd parties to add kernel extensions. Added bonus of making
> it slightly easier to port other code from FreeBSD.
>
> Diffs for your perusal at:
>
> ftp://ftp.netbsd.org/pub/incoming/thorpej/malloc-diffs
> ftp://ftp.netbsd.org/pub/incoming/thorpej/vmstat-diffs
There's a comment in one of the diffs that says "Types of memory to be
allocated (don't forget to update malloc.9)", but I don't see an
update to that man page for the different interface to kernel malloc.
But, yes, this is a nice addition.
Thanks,
Alistair