Re: [PATCH] Use inline function dst_metric() instead of direct access to dst->metric[]

[Satoru SATOH <satoru.satoh@gmail.com>]

Sorry, resend it.


There are functions to refer to the value of dst->metric[THE_METRIC-1] directly
without use of a inline function "dst_metric" defined in net/dst.h.

The following patch changes them to use the inline function consistently.

Signed-off-by: Satoru SATOH <satoru.satoh@gmail.com>

  net/decnet/dn_route.c |    4 ++--
  net/ipv4/route.c      |    2 +-
  net/ipv4/tcp_input.c  |   15 ++++++++-------
  3 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c
index 2f665a5..9c23160 100644
--- a/net/decnet/dn_route.c
+++ b/net/decnet/dn_route.c
@@ -235,14 +235,14 @@ static void dn_dst_update_pmtu(struct dst_entry *dst, u32 mtu)
  	else
  		min_mtu -= 21;

-	if (dst->metrics[RTAX_MTU-1] > mtu && mtu >= min_mtu) {
+	if (dst_metric(dst, RTAX_MTU) > mtu && mtu >= min_mtu) {
  		if (!(dst_metric_locked(dst, RTAX_MTU))) {
  			dst->metrics[RTAX_MTU-1] = mtu;
  			dst_set_expires(dst, dn_rt_mtu_expires);
  		}
  		if (!(dst_metric_locked(dst, RTAX_ADVMSS))) {
  			u32 mss = mtu - DN_MAX_NSP_DATA_HEADER;
-			if (dst->metrics[RTAX_ADVMSS-1] > mss)
+			if (dst_metric(dst, RTAX_ADVMSS) > mss)
  				dst->metrics[RTAX_ADVMSS-1] = mss;
  		}
  	}
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index ce25a13..e83a37b 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1491,7 +1491,7 @@ unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph,

  static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
  {
-	if (dst->metrics[RTAX_MTU-1] > mtu && mtu >= 68 &&
+	if (dst_metric(dst, RTAX_MTU) > mtu && mtu >= 68 &&
  	    !(dst_metric_locked(dst, RTAX_MTU))) {
  		if (mtu < ip_rt_min_pmtu) {
  			mtu = ip_rt_min_pmtu;
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 0298f80..3754055 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -66,6 +66,7 @@
  #include <linux/mm.h>
  #include <linux/module.h>
  #include <linux/sysctl.h>
+#include <net/dst.h>
  #include <net/tcp.h>
  #include <net/inet_common.h>
  #include <linux/ipsec.h>
@@ -605,7 +606,7 @@ static u32 tcp_rto_min(struct sock *sk)
  	u32 rto_min = TCP_RTO_MIN;

  	if (dst && dst_metric_locked(dst, RTAX_RTO_MIN))
-		rto_min = dst->metrics[RTAX_RTO_MIN - 1];
+		rto_min = dst_metric(dst, RTAX_RTO_MIN);
  	return rto_min;
  }

@@ -769,7 +770,7 @@ void tcp_update_metrics(struct sock *sk)
  				dst->metrics[RTAX_RTTVAR - 1] = m;
  			else
  				dst->metrics[RTAX_RTTVAR-1] -=
-					(dst->metrics[RTAX_RTTVAR-1] - m)>>2;
+					(dst_metric(dst, RTAX_RTTVAR) - m)>>2;
  		}

  		if (tp->snd_ssthresh >= 0xFFFF) {
@@ -788,21 +789,21 @@ void tcp_update_metrics(struct sock *sk)
  				dst->metrics[RTAX_SSTHRESH-1] =
  					max(tp->snd_cwnd >> 1, tp->snd_ssthresh);
  			if (!dst_metric_locked(dst, RTAX_CWND))
-				dst->metrics[RTAX_CWND-1] = (dst->metrics[RTAX_CWND-1] + tp->snd_cwnd) >> 1;
+				dst->metrics[RTAX_CWND-1] = (dst_metric(dst, RTAX_CWND) + tp->snd_cwnd) >> 1;
  		} else {
  			/* Else slow start did not finish, cwnd is non-sense,
  			   ssthresh may be also invalid.
  			 */
  			if (!dst_metric_locked(dst, RTAX_CWND))
-				dst->metrics[RTAX_CWND-1] = (dst->metrics[RTAX_CWND-1] + tp->snd_ssthresh) >> 1;
-			if (dst->metrics[RTAX_SSTHRESH-1] &&
+				dst->metrics[RTAX_CWND-1] = (dst_metric(dst, RTAX_CWND) + tp->snd_ssthresh) >> 1;
+			if (dst_metric(dst, RTAX_SSTHRESH) &&
  			    !dst_metric_locked(dst, RTAX_SSTHRESH) &&
-			    tp->snd_ssthresh > dst->metrics[RTAX_SSTHRESH-1])
+			    tp->snd_ssthresh > dst_metric(dst, RTAX_SSTHRESH))
  				dst->metrics[RTAX_SSTHRESH-1] = tp->snd_ssthresh;
  		}

  		if (!dst_metric_locked(dst, RTAX_REORDERING)) {
-			if (dst->metrics[RTAX_REORDERING-1] < tp->reordering &&
+			if (dst_metric(dst, RTAX_REORDERING) < tp->reordering &&
  			    tp->reordering != sysctl_tcp_reordering)
  				dst->metrics[RTAX_REORDERING-1] = tp->reordering;
  		}