This patch set removes the leaf_info structure from the IPv4 fib_trie. The
general idea is that the leaf_info structure itself only held about 6
actual bits of data, beyond that it was mostly just waste. As such we can
drop the structure, move the 1 byte representing the prefix/suffix length
into the fib_alias and just link it all into one list.
My testing shows that this saves somewhere between 4 to 10ns depending on
the type of test performed. I'm suspecting that this represents 1 to 2 L1
cache misses saved per look-up.
One side effect of this change is that semantic_match_miss will now only
increment once per leaf instead of once per leaf_info miss. However the
stat is already skewed now that we perform a preliminary check on the leaf
as a part of the look-up.
I also have gone through and addressed a number of ordering issues in the
first patch since I had misread the behavior of list_add_tail.
I have since run some additional testing and verified the resulting lists
are in the same order when combining multiple prefix length and tos values
in a single leaf.
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Signed-off-by: David S. Miller <davem@davemloft.net>