[PATCH 3/3] [NET]: Improve gnet_stats_* dumping logic to be less error prone

[Thomas Graf <tgraf@xxxxxxx>]

# This is a BitKeeper generated diff -Nru style patch.
#
# ChangeSet
#   2005/04/01 15:01:24+02:00 tgraf@xxxxxxx 
#   [NET]: Improve gnet_stats_* dumping logic to be less error prone
#   
#   The recent additions to make gnet_stats_* useable for action
#   statistics dumping in two steps introcuded a few error prone
#   assumptions which can easly be forgotten. This patch fixes this
#   up by simplifying the process of adding new fields to struct
#   gnet_dump or adding additional backward compatibility TLVs.
#   
#   Signed-off-by: Thomas Graf <tgraf@xxxxxxx>
#   Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
# 
# net/core/gen_stats.c
#   2005/04/01 15:01:12+02:00 tgraf@xxxxxxx +24 -13
#   [NET]: Improve gnet_stats_* dumping logic to be less error prone
# 
diff -Nru a/net/core/gen_stats.c b/net/core/gen_stats.c
--- a/net/core/gen_stats.c      2005-04-02 01:18:26 +02:00
+++ b/net/core/gen_stats.c      2005-04-02 01:18:26 +02:00
@@ -26,9 +26,7 @@
 static inline int
 gnet_stats_copy(struct gnet_dump *d, int type, void *buf, int size)
 {
-       if (type)
-               RTA_PUT(d->skb, type, size, buf);
-
+       RTA_PUT(d->skb, type, size, buf);
        return 0;
 
 rtattr_failure:
@@ -58,6 +56,8 @@
 gnet_stats_start_copy_compat(struct sk_buff *skb, int type, int tc_stats_type,
        int xstats_type, spinlock_t *lock, struct gnet_dump *d)
 {
+       memset(d, 0, sizeof(*d));
+       
        spin_lock_bh(lock);
        d->lock = lock;
        if (type)
@@ -65,12 +65,11 @@
        d->skb = skb;
        d->compat_tc_stats = tc_stats_type;
        d->compat_xstats = xstats_type;
-       d->xstats = NULL;
 
-       if (d->compat_tc_stats)
-               memset(&d->tc_stats, 0, sizeof(d->tc_stats));
+       if (d->tail)
+               return gnet_stats_copy(d, type, NULL, 0);
 
-       return gnet_stats_copy(d, type, NULL, 0);
+       return 0;
 }
 
 /**
@@ -111,8 +110,11 @@
                d->tc_stats.bytes = b->bytes;
                d->tc_stats.packets = b->packets;
        }
-       
-       return gnet_stats_copy(d, TCA_STATS_BASIC, b, sizeof(*b));
+
+       if (d->tail)
+               return gnet_stats_copy(d, TCA_STATS_BASIC, b, sizeof(*b));
+
+       return 0;
 }
 
 /**
@@ -134,7 +136,10 @@
                d->tc_stats.pps = r->pps;
        }
 
-       return gnet_stats_copy(d, TCA_STATS_RATE_EST, r, sizeof(*r));
+       if (d->tail)
+               return gnet_stats_copy(d, TCA_STATS_RATE_EST, r, sizeof(*r));
+
+       return 0;
 }
 
 /**
@@ -157,8 +162,11 @@
                d->tc_stats.backlog = q->backlog;
                d->tc_stats.overlimits = q->overlimits;
        }
-               
-       return gnet_stats_copy(d, TCA_STATS_QUEUE, q, sizeof(*q));
+
+       if (d->tail)
+               return gnet_stats_copy(d, TCA_STATS_QUEUE, q, sizeof(*q));
+
+       return 0;
 }
 
 /**
@@ -182,7 +190,10 @@
                d->xstats_len = len;
        }
 
-       return gnet_stats_copy(d, TCA_STATS_APP, st, len);
+       if (d->tail)
+               return gnet_stats_copy(d, TCA_STATS_APP, st, len);
+
+       return 0;
 }
 
 /**