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tcp: de-bloat a bit with factoring NET_INC_STATS_BH out

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There are some places in TCP that select one MIB index to
bump snmp statistics like this:

	if (<something>)
		NET_INC_STATS_BH(<some_id>);
	else if (<something_else>)
		NET_INC_STATS_BH(<some_other_id>);
	...
	else
		NET_INC_STATS_BH(<default_id>);

or in a more tricky but still similar way.

On the other hand, this NET_INC_STATS_BH is a camouflaged
increment of percpu variable, which is not that small.

Factoring those cases out de-bloats 235 bytes on non-preemptible
i386 config and drives parts of the code into 80 columns.

add/remove: 0/0 grow/shrink: 0/7 up/down: 0/-235 (-235)
function                                     old     new   delta
tcp_fastretrans_alert                       1437    1424     -13
tcp_dsack_set                                137     124     -13
tcp_xmit_retransmit_queue                    690     676     -14
tcp_try_undo_recovery                        283     265     -18
tcp_sacktag_write_queue                     1550    1515     -35
tcp_update_reordering                        162     106     -56
tcp_retransmit_timer                         990     904     -86

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Pavel Emelyanov
2008-07-03 01:05:41 -07:00
committed by David S. Miller
parent b4653e9945
commit 40b215e594
3 changed files with 46 additions and 22 deletions
Download Patch File Download Diff File Expand all files Collapse all files

7
net/ipv4/tcp_output.c
View File

@@ -1985,14 +1985,17 @@ void tcp_xmit_retransmit_queue(struct sock *sk)
if (sacked & TCPCB_LOST) {
if (!(sacked & (TCPCB_SACKED_ACKED|TCPCB_SACKED_RETRANS))) {
int mib_idx;
if (tcp_retransmit_skb(sk, skb)) {
tp->retransmit_skb_hint = NULL;
return;
}
if (icsk->icsk_ca_state != TCP_CA_Loss)
NET_INC_STATS_BH(LINUX_MIB_TCPFASTRETRANS);
mib_idx = LINUX_MIB_TCPFASTRETRANS;
else
NET_INC_STATS_BH(LINUX_MIB_TCPSLOWSTARTRETRANS);
mib_idx = LINUX_MIB_TCPSLOWSTARTRETRANS;
NET_INC_STATS_BH(mib_idx);
if (skb == tcp_write_queue_head(sk))
inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,