tcp: kill pointless urg_mode

It all started from me noticing that this urgent check in
tcp_clean_rtx_queue is unnecessarily inside the loop. Then
I took a longer look to it and found out that the users of
urg_mode can trivially do without, well almost, there was
one gotcha.

Bonus: those funny people who use urg with >= 2^31 write_seq -
snd_una could now rejoice too (that's the only purpose for the
between being there, otherwise a simple compare would have done
the thing). Not that I assume that the rest of the tcp code
happily lives with such mind-boggling numbers :-). Alas, it
turned out to be impossible to set wmem to such numbers anyway,
yes I really tried a big sendfile after setting some wmem but
nothing happened :-). ...Tcp_wmem is int and so is sk_sndbuf...
So I hacked a bit variable to long and found out that it seems
to work... :-)

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 5 deletions

diff --git a/include/linux/tcp.h b/include/linux/tcp.h
index 767290628292..fe77e1499ab7 100644
--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h
@@ -312,8 +312,11 @@ struct tcp_sock {
         u32     retrans_out;    /* Retransmitted packets out            */
 
         u16     urg_data;       /* Saved octet of OOB data and control flags */
-        u8      urg_mode;       /* In urgent mode               */
         u8      ecn_flags;      /* ECN status bits.                     */
+        u8      reordering;     /* Packet reordering metric.            */
+        u32     snd_up;         /* Urgent pointer               */
+
+        u8      keepalive_probes; /* num of allowed keep alive probes   */
 /*
  *      Options received (usually on last packet, some only on SYN packets).
  */
@@ -361,8 +364,6 @@ struct tcp_sock {
 
         u32     lost_retrans_low;       /* Sent seq after any rxmit (lowest) */
 
-        u8      reordering;     /* Packet reordering metric.            */
-        u8      keepalive_probes; /* num of allowed keep alive probes   */
         u32     prior_ssthresh; /* ssthresh saved at recovery start     */
         u32     high_seq;       /* snd_nxt at onset of congestion       */
 
@@ -374,8 +375,6 @@ struct tcp_sock {
         u32     total_retrans;  /* Total retransmits for entire connection */
 
         u32     urg_seq;        /* Seq of received urgent pointer */
-        u32     snd_up;         /* Urgent pointer               */
-
         unsigned int            keepalive_time;   /* time before keep alive takes place */
         unsigned int            keepalive_intvl;  /* time interval between keep alive probes */