Hi Peter,
On Mon, 2018-07-09 at 16:10 +0200, Peter Zijlstra wrote:
On Mon, Jul 09, 2018 at 04:07:17PM +0200, Peter Zijlstra wrote:
On Mon, Jul 09, 2018 at 04:45:50PM +0300, Alexey Brodkin wrote:
--- a/drivers/base/devres.c +++ b/drivers/base/devres.c @@ -24,8 +24,12 @@ struct devres_node { struct devres { struct devres_node node;
- /* -- 3 pointers */
- unsigned long long data[]; /* guarantee ull alignment */
- /*
* data[] must be 64 bit aligned even on 32 bit architectures
* because it might be accessed by instructions that require
* aligned memory arguments such as atomic64_t.
*/
- u8 __aligned(8) data[];
};
Seeing that this ends up in a semi generic allocation thing, I don't feel this should be different from ARCH_KMALLOC_MINALIGN.
In fact, since alloc_dr() uses kmalloc() to allocate the entire thing, it is impossible to guarantee a larger alignment than kmalloc does.
Well but 4-bytes [which is critical for atomic64_t] should be much less than a sane cache line length so above should work.
-Alexey