netfilter: nf_conntrack: use atomic64 for accounting counters
We can use atomic64_t infrastructure to avoid taking a spinlock in fast
path, and remove inaccuracies while reading values in
ctnetlink_dump_counters() and connbytes_mt() on 32bit arches.
Suggested by Pablo.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/net/netfilter/xt_connbytes.c b/net/netfilter/xt_connbytes.c
index 5b13850..2b8418c 100644
--- a/net/netfilter/xt_connbytes.c
+++ b/net/netfilter/xt_connbytes.c
@@ -40,46 +40,46 @@
case XT_CONNBYTES_PKTS:
switch (sinfo->direction) {
case XT_CONNBYTES_DIR_ORIGINAL:
- what = counters[IP_CT_DIR_ORIGINAL].packets;
+ what = atomic64_read(&counters[IP_CT_DIR_ORIGINAL].packets);
break;
case XT_CONNBYTES_DIR_REPLY:
- what = counters[IP_CT_DIR_REPLY].packets;
+ what = atomic64_read(&counters[IP_CT_DIR_REPLY].packets);
break;
case XT_CONNBYTES_DIR_BOTH:
- what = counters[IP_CT_DIR_ORIGINAL].packets;
- what += counters[IP_CT_DIR_REPLY].packets;
+ what = atomic64_read(&counters[IP_CT_DIR_ORIGINAL].packets);
+ what += atomic64_read(&counters[IP_CT_DIR_REPLY].packets);
break;
}
break;
case XT_CONNBYTES_BYTES:
switch (sinfo->direction) {
case XT_CONNBYTES_DIR_ORIGINAL:
- what = counters[IP_CT_DIR_ORIGINAL].bytes;
+ what = atomic64_read(&counters[IP_CT_DIR_ORIGINAL].bytes);
break;
case XT_CONNBYTES_DIR_REPLY:
- what = counters[IP_CT_DIR_REPLY].bytes;
+ what = atomic64_read(&counters[IP_CT_DIR_REPLY].bytes);
break;
case XT_CONNBYTES_DIR_BOTH:
- what = counters[IP_CT_DIR_ORIGINAL].bytes;
- what += counters[IP_CT_DIR_REPLY].bytes;
+ what = atomic64_read(&counters[IP_CT_DIR_ORIGINAL].bytes);
+ what += atomic64_read(&counters[IP_CT_DIR_REPLY].bytes);
break;
}
break;
case XT_CONNBYTES_AVGPKT:
switch (sinfo->direction) {
case XT_CONNBYTES_DIR_ORIGINAL:
- bytes = counters[IP_CT_DIR_ORIGINAL].bytes;
- pkts = counters[IP_CT_DIR_ORIGINAL].packets;
+ bytes = atomic64_read(&counters[IP_CT_DIR_ORIGINAL].bytes);
+ pkts = atomic64_read(&counters[IP_CT_DIR_ORIGINAL].packets);
break;
case XT_CONNBYTES_DIR_REPLY:
- bytes = counters[IP_CT_DIR_REPLY].bytes;
- pkts = counters[IP_CT_DIR_REPLY].packets;
+ bytes = atomic64_read(&counters[IP_CT_DIR_REPLY].bytes);
+ pkts = atomic64_read(&counters[IP_CT_DIR_REPLY].packets);
break;
case XT_CONNBYTES_DIR_BOTH:
- bytes = counters[IP_CT_DIR_ORIGINAL].bytes +
- counters[IP_CT_DIR_REPLY].bytes;
- pkts = counters[IP_CT_DIR_ORIGINAL].packets +
- counters[IP_CT_DIR_REPLY].packets;
+ bytes = atomic64_read(&counters[IP_CT_DIR_ORIGINAL].bytes) +
+ atomic64_read(&counters[IP_CT_DIR_REPLY].bytes);
+ pkts = atomic64_read(&counters[IP_CT_DIR_ORIGINAL].packets) +
+ atomic64_read(&counters[IP_CT_DIR_REPLY].packets);
break;
}
if (pkts != 0)