mirror of https://gitee.com/openkylin/linux.git
cf4b24f002
Nexthops for MPLS routes have a via address field sized for the largest via address that is expected, which is 32 bytes. This means that in the most common case of having ipv4 via addresses, 28 bytes of memory more than required are used per nexthop. In the other common case of an ipv6 nexthop then 16 bytes more than required are used. With large numbers of MPLS routes this extra memory usage could start to become significant. To avoid allocating memory for a maximum length via address when not all of it is required and to allow for ease of iterating over nexthops, then the via addresses are changed to be stored in the same memory block as the route and nexthops, but in an array after the end of the array of nexthops. New accessors are provided to retrieve a pointer to the via address. To allow for O(1) access without having to store a pointer or offset per nh, the via address for each nexthop is sized according to the maximum via address for any nexthop in the route, which is stored in a new route field, rt_max_alen, but this is in an existing hole in struct mpls_route so it doesn't increase the size of the structure. Each via address is ensured to be aligned to VIA_ALEN_ALIGN to account for architectures that don't allow unaligned accesses. Signed-off-by: Robert Shearman <rshearma@brocade.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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| .. | ||
| Kconfig | ||
| Makefile | ||
| af_mpls.c | ||
| internal.h | ||
| mpls_gso.c | ||
| mpls_iptunnel.c | ||