lkml.org 
[lkml]   [2018]   [Jan]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: kmem_cache_attr (was Re: [PATCH 04/36] usercopy: Prepare for usercopy whitelisting)
On Tue, 16 Jan 2018, Matthew Wilcox wrote:

> > Sure this data is never changed. It can be const.
>
> It's changed at initialisation. Look:
>
> kmem_cache_create(const char *name, size_t size, size_t align,
> slab_flags_t flags, void (*ctor)(void *))
> s = create_cache(cache_name, size, size,
> calculate_alignment(flags, align, size),
> flags, ctor, NULL, NULL);
>
> The 'align' that ends up in s->align, is not the user-specified align.
> It's also dependent on runtime information (cache_line_size()), so it
> can't be calculated at compile time.

Then we would need another align field in struct kmem_cache that takes the
changes value?

> 'flags' also gets mangled:
> flags &= CACHE_CREATE_MASK;

Well ok then that also belongs into kmem_cache and the original value
stays in kmem_cache_attr.

> unsigned int would be my preference.

Great.

\
 
 \ /
  Last update: 2018-01-16 19:09    [W:0.070 / U:2.208 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site