Re: [linux-next:master 12891/13017] mm/slub.c:2396:1: warning: '___slab_alloc' uses dynamic stack allocation

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> On Fri, 13 Nov 2015, Andreas Krebbel1 wrote:
> 
> > this appears to be the result of aligning struct page to more than 8 
bytes
> > and putting it onto the stack - wich is only 8 bytes aligned.  The
> > compiler has to perform runtime alignment to achieve that. It 
allocates
> > memory using *alloca* and does the math with the returned pointer. Our
> > dynamic stack allocation option basically only checks if there is an
> > alloca user.
> 
> The slub uses of struct page only require an alignment of the page 
struct
> on the stack to a word. So its fine.

Our compare and swap double hardware instruction unfortunately requires 16 
byte alignment. That's probably the reason why this alignment has been 
picked. So I don't think that we can easily get rid of it.

-Andreas-

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