summaryrefslogtreecommitdiffstats
path: root/include
diff options
context:
space:
mode:
authorDavid Held <drheld@google.com>2014-07-15 23:28:32 -0400
committerDavid S. Miller <davem@davemloft.net>2014-07-16 23:29:52 -0700
commit2dc41cff7545d55c6294525c811594576f8e119c (patch)
treecab09b28d188606139b1b50b661f42da157c52ba /include
parent5cf3d46192fccf68b4a4759e4d7346e41c669a76 (diff)
downloadlinux-2dc41cff7545d55c6294525c811594576f8e119c.tar.bz2
udp: Use hash2 for long hash1 chains in __udp*_lib_mcast_deliver.
Many multicast sources can have the same port which can result in a very large list when hashing by port only. Hash by address and port instead if this is the case. This makes multicast more similar to unicast. On a 24-core machine receiving from 500 multicast sockets on the same port, before this patch 80% of system CPU was used up by spin locking and only ~25% of packets were successfully delivered. With this patch, all packets are delivered and kernel overhead is ~8% system CPU on spinlocks. Signed-off-by: David Held <drheld@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
-rw-r--r--include/net/sock.h14
1 files changed, 14 insertions, 0 deletions
diff --git a/include/net/sock.h b/include/net/sock.h
index 29e48a6d1ded..28f734601b50 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -660,6 +660,20 @@ static inline void sk_add_bind_node(struct sock *sk,
#define sk_for_each_bound(__sk, list) \
hlist_for_each_entry(__sk, list, sk_bind_node)
+/**
+ * sk_nulls_for_each_entry_offset - iterate over a list at a given struct offset
+ * @tpos: the type * to use as a loop cursor.
+ * @pos: the &struct hlist_node to use as a loop cursor.
+ * @head: the head for your list.
+ * @offset: offset of hlist_node within the struct.
+ *
+ */
+#define sk_nulls_for_each_entry_offset(tpos, pos, head, offset) \
+ for (pos = (head)->first; \
+ (!is_a_nulls(pos)) && \
+ ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \
+ pos = pos->next)
+
static inline struct user_namespace *sk_user_ns(struct sock *sk)
{
/* Careful only use this in a context where these parameters