net/xps: Fix calculation of initial number of xps queues

The existing code breaks on architectures where the L1 cache size
(L1_CACHE_BYTES) is smaller or equal the size of struct xps_map.

The new code ensures that we get at minimum one initial xps queue, or even more
as long as it fits into the next multiple of L1_CACHE_SIZE.

Signed-off-by: Helge Deller <deller@gmx.de>
Acked-by: Alexander Duyck <aduyck@mirantis.com>
This commit is contained in:
Helge Deller 2015-10-25 10:00:32 +01:00
parent b696e5e938
commit c59f419bdd

View File

@ -718,8 +718,8 @@ struct xps_map {
u16 queues[0];
};
#define XPS_MAP_SIZE(_num) (sizeof(struct xps_map) + ((_num) * sizeof(u16)))
#define XPS_MIN_MAP_ALLOC ((L1_CACHE_BYTES - sizeof(struct xps_map)) \
/ sizeof(u16))
#define XPS_MIN_MAP_ALLOC ((L1_CACHE_ALIGN(offsetof(struct xps_map, queues[1])) \
- sizeof(struct xps_map)) / sizeof(u16))
/*
* This structure holds all XPS maps for device. Maps are indexed by CPU.