From 98298e6ca6d5908f96e529e70a254a4d5bf754e7 Mon Sep 17 00:00:00 2001 From: Matteo Croce Date: Tue, 29 Oct 2019 14:50:50 +0100 Subject: flow_dissector: add meaningful comments Documents two piece of code which can't be understood at a glance. Signed-off-by: Matteo Croce Signed-off-by: David S. Miller --- net/core/flow_dissector.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'net/core/flow_dissector.c') diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index dbf502c18656..bc22b384ac6c 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -1408,6 +1408,9 @@ static inline size_t flow_keys_hash_length(const struct flow_keys *flow) { size_t diff = FLOW_KEYS_HASH_OFFSET + sizeof(flow->addrs); BUILD_BUG_ON((sizeof(*flow) - FLOW_KEYS_HASH_OFFSET) % sizeof(u32)); + /* flow.addrs MUST be the last member in struct flow_keys because + * different L3 protocols have different address length + */ BUILD_BUG_ON(offsetof(typeof(*flow), addrs) != sizeof(*flow) - sizeof(flow->addrs)); @@ -1455,6 +1458,9 @@ __be32 flow_get_u32_dst(const struct flow_keys *flow) } EXPORT_SYMBOL(flow_get_u32_dst); +/* Sort the source and destination IP (and the ports if the IP are the same), + * to have consistent hash within the two directions + */ static inline void __flow_hash_consistentify(struct flow_keys *keys) { int addr_diff, i; -- cgit v1.2.3-59-g8ed1b