percpu: Make __verify_pcu_ptr handle per cpu pointers to arrays

__verify_pcpu_ptr() will cause a compilation failure if the type of the
pointer is a pointer to a fixed array of objects. Adding zero to the
pointer converts the type of pointer to that pointing to a single
object of the array.

Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Christoph Lameter 2013-08-23 19:01:58 +00:00 committed by Tejun Heo
parent a4244454df
commit abec1a806e
1 changed files with 4 additions and 1 deletions

View File

@ -22,9 +22,12 @@
* Macro which verifies @ptr is a percpu pointer without evaluating * Macro which verifies @ptr is a percpu pointer without evaluating
* @ptr. This is to be used in percpu accessors to verify that the * @ptr. This is to be used in percpu accessors to verify that the
* input parameter is a percpu pointer. * input parameter is a percpu pointer.
*
* + 0 is required in order to convert the pointer type from a
* potential array type to a pointer to a single item of the array.
*/ */
#define __verify_pcpu_ptr(ptr) do { \ #define __verify_pcpu_ptr(ptr) do { \
const void __percpu *__vpp_verify = (typeof(ptr))NULL; \ const void __percpu *__vpp_verify = (typeof((ptr) + 0))NULL; \
(void)__vpp_verify; \ (void)__vpp_verify; \
} while (0) } while (0)