From de7d5084d82794a8e83afb994fcb07f82da3cd7b Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 7 Nov 2019 16:27:14 -0800 Subject: net: provide dev_lstats_read() helper Many network drivers use hand-coded implementation of the same thing, let's factorize things so that u64_stats_t adoption is done once. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- drivers/net/loopback.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) (limited to 'drivers/net/loopback.c') diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c index 14545a8797a8..92336ac4c5e6 100644 --- a/drivers/net/loopback.c +++ b/drivers/net/loopback.c @@ -99,13 +99,13 @@ static netdev_tx_t loopback_xmit(struct sk_buff *skb, return NETDEV_TX_OK; } -static void loopback_get_stats64(struct net_device *dev, - struct rtnl_link_stats64 *stats) +void dev_lstats_read(struct net_device *dev, u64 *packets, u64 *bytes) { - u64 bytes = 0; - u64 packets = 0; int i; + *packets = 0; + *bytes = 0; + for_each_possible_cpu(i) { const struct pcpu_lstats *lb_stats; u64 tbytes, tpackets; @@ -114,12 +114,22 @@ static void loopback_get_stats64(struct net_device *dev, lb_stats = per_cpu_ptr(dev->lstats, i); do { start = u64_stats_fetch_begin_irq(&lb_stats->syncp); - tbytes = lb_stats->bytes; tpackets = lb_stats->packets; + tbytes = lb_stats->bytes; } while (u64_stats_fetch_retry_irq(&lb_stats->syncp, start)); - bytes += tbytes; - packets += tpackets; + *bytes += tbytes; + *packets += tpackets; } +} +EXPORT_SYMBOL(dev_lstats_read); + +static void loopback_get_stats64(struct net_device *dev, + struct rtnl_link_stats64 *stats) +{ + u64 packets, bytes; + + dev_lstats_read(dev, &packets, &bytes); + stats->rx_packets = packets; stats->tx_packets = packets; stats->rx_bytes = bytes; -- cgit v1.2.3 From dd5382a08157756510aa8d7269c662eccde775cb Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 7 Nov 2019 16:27:15 -0800 Subject: net: provide dev_lstats_add() helper Many network drivers need it and hand-coded the same function. In order to ease u64_stats_t adoption, it is time to factorize. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- drivers/net/loopback.c | 12 ++---------- 1 file changed, 2 insertions(+), 10 deletions(-) (limited to 'drivers/net/loopback.c') diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c index 92336ac4c5e6..47ad2478b9f3 100644 --- a/drivers/net/loopback.c +++ b/drivers/net/loopback.c @@ -68,7 +68,6 @@ EXPORT_SYMBOL(blackhole_netdev); static netdev_tx_t loopback_xmit(struct sk_buff *skb, struct net_device *dev) { - struct pcpu_lstats *lb_stats; int len; skb_tx_timestamp(skb); @@ -85,16 +84,9 @@ static netdev_tx_t loopback_xmit(struct sk_buff *skb, skb->protocol = eth_type_trans(skb, dev); - /* it's OK to use per_cpu_ptr() because BHs are off */ - lb_stats = this_cpu_ptr(dev->lstats); - len = skb->len; - if (likely(netif_rx(skb) == NET_RX_SUCCESS)) { - u64_stats_update_begin(&lb_stats->syncp); - lb_stats->bytes += len; - lb_stats->packets++; - u64_stats_update_end(&lb_stats->syncp); - } + if (likely(netif_rx(skb) == NET_RX_SUCCESS)) + dev_lstats_add(dev, len); return NETDEV_TX_OK; } -- cgit v1.2.3 From fd2f4737870eb866537fbbffa2b59414b9b0c0a2 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 7 Nov 2019 16:27:22 -0800 Subject: net: use u64_stats_t in struct pcpu_lstats In order to fix the data-race found by KCSAN, we can use the new u64_stats_t type and its accessors instead of plain u64 fields. This will still generate optimal code for both 32 and 64 bit platforms. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- drivers/net/loopback.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/net/loopback.c') diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c index 47ad2478b9f3..a1c77cc00416 100644 --- a/drivers/net/loopback.c +++ b/drivers/net/loopback.c @@ -106,8 +106,8 @@ void dev_lstats_read(struct net_device *dev, u64 *packets, u64 *bytes) lb_stats = per_cpu_ptr(dev->lstats, i); do { start = u64_stats_fetch_begin_irq(&lb_stats->syncp); - tpackets = lb_stats->packets; - tbytes = lb_stats->bytes; + tpackets = u64_stats_read(&lb_stats->packets); + tbytes = u64_stats_read(&lb_stats->bytes); } while (u64_stats_fetch_retry_irq(&lb_stats->syncp, start)); *bytes += tbytes; *packets += tpackets; -- cgit v1.2.3