Re: [RFC] [PATCH] kmem_alloc (generic wrapper for kmalloc and vmalloc)

[Carl-Daniel Hailfinger <c-d.hailfinger.kernel.2004@gmx.net>]

Jens Axboe wrote:
> On Wed, Nov 10 2004, Robert Love wrote:
> 
>>On Wed, 2004-11-10 at 06:19 +0100, Carl-Daniel Hailfinger wrote:
>>
>>>it seems there is a bunch of drivers which want to allocate memory as
>>>efficiently as possible in a wide range of allocation sizes. XFS and
>>>NTFS seem to be examples. Implement a generic wrapper to reduce code
>>>duplication.
>>>Functions have the my_ prefixes to avoid name clash with XFS.
>>
>>No, no, no.  A good patch would be fixing places where you see this.
>>
>>Code needs to conscientiously decide to use vmalloc over kmalloc.  The
>>behavior is different and the choice needs to be explicit.
> 
> Plus, you cannot use vfree() from interrupt context. This patch is a bad
> idea.

OK, so how should I allocate memory for 512 struct loop_device's?
Because of its odd size (304 bytes) it seems that if I use kmalloc
seperately for each struct, I'd waste 208 bytes per allocation. 68%
overhead would be a step backwards. Or am I missing something here?


Regards,
Carl-Daniel