From 7dd1bf28ccc44ef205c64aab618863faa914daa9 Mon Sep 17 00:00:00 2001 From: Allan Stephens Date: Mon, 23 May 2011 16:23:32 -0400 Subject: [PATCH] tipc: Optimizations & corrections to message rejection Optimizes the creation of a returned payload message by duplicating the original message and then updating the small number of fields that need to be adjusted, rather than building the new message header from scratch. In addition, certain operations that are not always required are relocated so that they are only done if needed. These optimizations also have the effect of addressing other issues that were present previously: 1) Fixes a bug that caused the socket send routines to return the size of the returned message, rather than the size of the sent message, when a returnable payload message was sent to a non-existent destination port. 2) The message header of the returned message now matches that of the original message more closely. The header is now always the same size as the original header, and some message header fields that weren't being initialized in the returned message header are now populated correctly -- namely the "d" and "s" bits, and the upper bound of a multicast name instance (where present). Signed-off-by: Allan Stephens Signed-off-by: Paul Gortmaker --- net/tipc/port.c | 49 ++++++++++++++++++++++++------------------------- 1 file changed, 24 insertions(+), 25 deletions(-) diff --git a/net/tipc/port.c b/net/tipc/port.c index 70ecdfdf6e3..53118171b7e 100644 --- a/net/tipc/port.c +++ b/net/tipc/port.c @@ -358,14 +358,10 @@ int tipc_reject_msg(struct sk_buff *buf, u32 err) struct sk_buff *rbuf; struct tipc_msg *rmsg; int hdr_sz; - u32 imp = msg_importance(msg); + u32 imp; u32 data_sz = msg_data_sz(msg); u32 src_node; - - if (data_sz > MAX_REJECT_SIZE) - data_sz = MAX_REJECT_SIZE; - if (msg_connected(msg) && (imp < TIPC_CRITICAL_IMPORTANCE)) - imp++; + u32 rmsg_sz; /* discard rejected message if it shouldn't be returned to sender */ @@ -377,30 +373,33 @@ int tipc_reject_msg(struct sk_buff *buf, u32 err) if (msg_errcode(msg) || msg_dest_droppable(msg)) goto exit; - /* construct rejected message */ - if (msg_mcast(msg)) - hdr_sz = MCAST_H_SIZE; - else - hdr_sz = LONG_H_SIZE; - rbuf = tipc_buf_acquire(data_sz + hdr_sz); + /* + * construct returned message by copying rejected message header and + * data (or subset), then updating header fields that need adjusting + */ + + hdr_sz = msg_hdr_sz(msg); + rmsg_sz = hdr_sz + min_t(u32, data_sz, MAX_REJECT_SIZE); + + rbuf = tipc_buf_acquire(rmsg_sz); if (rbuf == NULL) goto exit; rmsg = buf_msg(rbuf); - tipc_msg_init(rmsg, imp, msg_type(msg), hdr_sz, msg_orignode(msg)); - msg_set_errcode(rmsg, err); - msg_set_destport(rmsg, msg_origport(msg)); - msg_set_origport(rmsg, msg_destport(msg)); - if (msg_short(msg)) { - msg_set_orignode(rmsg, tipc_own_addr); - /* leave name type & instance as zeroes */ - } else { - msg_set_orignode(rmsg, msg_destnode(msg)); - msg_set_nametype(rmsg, msg_nametype(msg)); - msg_set_nameinst(rmsg, msg_nameinst(msg)); + skb_copy_to_linear_data(rbuf, msg, rmsg_sz); + + if (msg_connected(rmsg)) { + imp = msg_importance(rmsg); + if (imp < TIPC_CRITICAL_IMPORTANCE) + msg_set_importance(rmsg, ++imp); } - msg_set_size(rmsg, data_sz + hdr_sz); - skb_copy_to_linear_data_offset(rbuf, hdr_sz, msg_data(msg), data_sz); + msg_set_non_seq(rmsg, 0); + msg_set_size(rmsg, rmsg_sz); + msg_set_errcode(rmsg, err); + msg_set_prevnode(rmsg, tipc_own_addr); + msg_swap_words(rmsg, 4, 5); + if (!msg_short(rmsg)) + msg_swap_words(rmsg, 6, 7); /* send self-abort message when rejecting on a connected port */ if (msg_connected(msg)) { -- 2.39.5