From ee7437669c542a9497f1c3a5dde7af19b7244e35 Mon Sep 17 00:00:00 2001 From: jaszha03 Date: Fri, 27 Sep 2019 12:52:18 -0500 Subject: ip: refactor ip4_mtrie to use atomic store-release ip4_mtrie used full memory barrier compare-and-swap in set_leaf () and set_root_leaf () even though only one thread updates the trie. Replaced such instances of compare-and-swap with atomic store-release. Type: refactor Change-Id: Ic6e3c84480697915541acd16dcc630d1c436137d Signed-off-by: Jason Zhang Reviewed-by: Lijian Zhang Reviewed-by: Ruifeng Wang --- src/vnet/ip/ip4_mtrie.c | 19 +++++-------------- 1 file changed, 5 insertions(+), 14 deletions(-) diff --git a/src/vnet/ip/ip4_mtrie.c b/src/vnet/ip/ip4_mtrie.c index be79883dde0..380ca324b64 100755 --- a/src/vnet/ip/ip4_mtrie.c +++ b/src/vnet/ip/ip4_mtrie.c @@ -254,8 +254,7 @@ set_ply_with_more_specific_leaf (ip4_fib_mtrie_t * m, else if (new_leaf_dst_address_bits >= ply->dst_address_bits_of_leaves[i]) { - clib_atomic_cmp_and_swap (&ply->leaves[i], old_leaf, new_leaf); - ASSERT (ply->leaves[i] == new_leaf); + clib_atomic_store_rel_n (&ply->leaves[i], new_leaf); ply->dst_address_bits_of_leaves[i] = new_leaf_dst_address_bits; ply->n_non_empty_leafs += ip4_fib_mtrie_leaf_is_non_empty (ply, i); } @@ -319,9 +318,7 @@ set_leaf (ip4_fib_mtrie_t * m, old_ply->dst_address_bits_of_leaves[i] = a->dst_address_length; - clib_atomic_cmp_and_swap (&old_ply->leaves[i], old_leaf, - new_leaf); - ASSERT (old_ply->leaves[i] == new_leaf); + clib_atomic_store_rel_n (&old_ply->leaves[i], new_leaf); old_ply->n_non_empty_leafs += ip4_fib_mtrie_leaf_is_non_empty (old_ply, i); @@ -378,9 +375,7 @@ set_leaf (ip4_fib_mtrie_t * m, /* Refetch since ply_create may move pool. */ old_ply = pool_elt_at_index (ip4_ply_pool, old_ply_index); - clib_atomic_cmp_and_swap (&old_ply->leaves[dst_byte], old_leaf, - new_leaf); - ASSERT (old_ply->leaves[dst_byte] == new_leaf); + clib_atomic_store_rel_n (&old_ply->leaves[dst_byte], new_leaf); old_ply->dst_address_bits_of_leaves[dst_byte] = ply_base_len; old_ply->n_non_empty_leafs += @@ -451,9 +446,7 @@ set_root_leaf (ip4_fib_mtrie_t * m, * the new one */ old_ply->dst_address_bits_of_leaves[slot] = a->dst_address_length; - clib_atomic_cmp_and_swap (&old_ply->leaves[slot], - old_leaf, new_leaf); - ASSERT (old_ply->leaves[slot] == new_leaf); + clib_atomic_store_rel_n (&old_ply->leaves[slot], new_leaf); } else { @@ -498,9 +491,7 @@ set_root_leaf (ip4_fib_mtrie_t * m, ply_base_len); new_ply = get_next_ply_for_leaf (m, new_leaf); - clib_atomic_cmp_and_swap (&old_ply->leaves[dst_byte], old_leaf, - new_leaf); - ASSERT (old_ply->leaves[dst_byte] == new_leaf); + clib_atomic_store_rel_n (&old_ply->leaves[dst_byte], new_leaf); old_ply->dst_address_bits_of_leaves[dst_byte] = ply_base_len; } else -- cgit 1.2.3-korg