From c353c7b7ffb7ae6ed8f3339906fe33c8be6cf344 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 8 Feb 2024 14:43:23 +0000 Subject: [PATCH] net-device: move lstats in net_device_read_txrx dev->lstats is notably used from loopback ndo_start_xmit() and other virtual drivers. Per cpu stats updates are dirtying per-cpu data, but the pointer itself is read-only. Fixes: 43a71cd66b9c ("net-device: reorganize net_device fast path variables") Signed-off-by: Eric Dumazet Cc: Coco Li Cc: Simon Horman Reviewed-by: Simon Horman Signed-off-by: David S. Miller --- Documentation/networking/net_cachelines/net_device.rst | 4 ++-- include/linux/netdevice.h | 10 +++++----- net/core/dev.c | 3 ++- 3 files changed, 9 insertions(+), 8 deletions(-) diff --git a/Documentation/networking/net_cachelines/net_device.rst b/Documentation/networking/net_cachelines/net_device.rst index e75a53593bb9..dceb49d56a91 100644 --- a/Documentation/networking/net_cachelines/net_device.rst +++ b/Documentation/networking/net_cachelines/net_device.rst @@ -136,8 +136,8 @@ struct_netpoll_info* npinfo - possible_net_t nd_net - read_mostly (dev_net)napi_busy_loop,tcp_v(4/6)_rcv,ip(v6)_rcv,ip(6)_input,ip(6)_input_finish void* ml_priv enum_netdev_ml_priv_type ml_priv_type -struct_pcpu_lstats__percpu* lstats -struct_pcpu_sw_netstats__percpu* tstats +struct_pcpu_lstats__percpu* lstats read_mostly dev_lstats_add() +struct_pcpu_sw_netstats__percpu* tstats read_mostly dev_sw_netstats_tx_add() struct_pcpu_dstats__percpu* dstats struct_garp_port* garp_port struct_mrp_port* mrp_port diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 118c40258d07..ef7bfbb98497 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2141,6 +2141,11 @@ struct net_device { /* TXRX read-mostly hotpath */ __cacheline_group_begin(net_device_read_txrx); + union { + struct pcpu_lstats __percpu *lstats; + struct pcpu_sw_netstats __percpu *tstats; + struct pcpu_dstats __percpu *dstats; + }; unsigned int flags; unsigned short hard_header_len; netdev_features_t features; @@ -2395,11 +2400,6 @@ struct net_device { enum netdev_ml_priv_type ml_priv_type; enum netdev_stat_type pcpu_stat_type:8; - union { - struct pcpu_lstats __percpu *lstats; - struct pcpu_sw_netstats __percpu *tstats; - struct pcpu_dstats __percpu *dstats; - }; #if IS_ENABLED(CONFIG_GARP) struct garp_port __rcu *garp_port; diff --git a/net/core/dev.c b/net/core/dev.c index cb2dab0feee0..9bb792cecc16 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -11652,11 +11652,12 @@ static void __init net_dev_struct_check(void) CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_tx, 160); /* TXRX read-mostly hotpath */ + CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, lstats); CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, flags); CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, hard_header_len); CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, features); CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, ip6_ptr); - CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_txrx, 30); + CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_txrx, 38); /* RX read-mostly hotpath */ CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, ptype_specific);