Allow per-NAPI gro_flush_timeout setting. The existing sysfs parameter is respected; writes to sysfs will write to all NAPI structs for the device and the net_device gro_flush_timeout field. Reads from sysfs will read from the net_device field. The ability to set gro_flush_timeout on specific NAPI instances will be added in a later commit, via netdev-genl. Signed-off-by: Joe Damato <jdamato@xxxxxxxxxx> --- Documentation/netlink/specs/netdev.yaml | 6 +++ .../networking/net_cachelines/net_device.rst | 1 - include/linux/netdevice.h | 2 +- include/uapi/linux/netdev.h | 1 + net/core/dev.c | 12 +++--- net/core/dev.h | 43 +++++++++++++++++++ net/core/net-sysfs.c | 2 +- net/core/netdev-genl.c | 5 +++ tools/include/uapi/linux/netdev.h | 1 + 9 files changed, 64 insertions(+), 9 deletions(-) diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/netlink/specs/netdev.yaml index e4219bfff08d..3034c480d0b4 100644 --- a/Documentation/netlink/specs/netdev.yaml +++ b/Documentation/netlink/specs/netdev.yaml @@ -259,6 +259,11 @@ attribute-sets: type: u32 checks: max: s32-max + - + name: gro-flush-timeout + doc: The timeout, in nanoseconds, of when to trigger the NAPI + watchdog timer and schedule NAPI processing. + type: uint - name: queue attributes: @@ -610,6 +615,7 @@ operations: - pid - index - defer-hard-irqs + - gro-flush-timeout dump: request: attributes: diff --git a/Documentation/networking/net_cachelines/net_device.rst b/Documentation/networking/net_cachelines/net_device.rst index 4cd801398c4e..048cc9d1eafc 100644 --- a/Documentation/networking/net_cachelines/net_device.rst +++ b/Documentation/networking/net_cachelines/net_device.rst @@ -98,7 +98,6 @@ struct_netdev_queue* _rx read_mostly unsigned_int num_rx_queues unsigned_int real_num_rx_queues - read_mostly get_rps_cpu struct_bpf_prog* xdp_prog - read_mostly netif_elide_gro() -unsigned_long gro_flush_timeout - read_mostly napi_complete_done unsigned_int gro_max_size - read_mostly skb_gro_receive unsigned_int gro_ipv4_max_size - read_mostly skb_gro_receive rx_handler_func_t* rx_handler read_mostly - __netif_receive_skb_core diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 5a58cf61539e..862c835bcf09 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2087,7 +2087,6 @@ struct net_device { int ifindex; unsigned int real_num_rx_queues; struct netdev_rx_queue *_rx; - unsigned long gro_flush_timeout; unsigned int gro_max_size; unsigned int gro_ipv4_max_size; rx_handler_func_t __rcu *rx_handler; @@ -2411,6 +2410,7 @@ struct net_device { /** @irq_moder: dim parameters used if IS_ENABLED(CONFIG_DIMLIB). */ struct dim_irq_moder *irq_moder; + unsigned long gro_flush_timeout; u32 napi_defer_hard_irqs; u8 priv[] ____cacheline_aligned diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h index bcc95b7ebd92..fd02b5b3b081 100644 --- a/include/uapi/linux/netdev.h +++ b/include/uapi/linux/netdev.h @@ -123,6 +123,7 @@ enum { NETDEV_A_NAPI_PID, NETDEV_A_NAPI_INDEX, NETDEV_A_NAPI_DEFER_HARD_IRQS, + NETDEV_A_NAPI_GRO_FLUSH_TIMEOUT, __NETDEV_A_NAPI_MAX, NETDEV_A_NAPI_MAX = (__NETDEV_A_NAPI_MAX - 1) diff --git a/net/core/dev.c b/net/core/dev.c index 9495448fedaa..a45a0dbcf711 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -6227,12 +6227,12 @@ bool napi_complete_done(struct napi_struct *n, int work_done) if (work_done) { if (n->gro_bitmask) - timeout = READ_ONCE(n->dev->gro_flush_timeout); + timeout = napi_get_gro_flush_timeout(n); n->defer_hard_irqs_count = napi_get_defer_hard_irqs(n); } if (n->defer_hard_irqs_count > 0) { n->defer_hard_irqs_count--; - timeout = READ_ONCE(n->dev->gro_flush_timeout); + timeout = napi_get_gro_flush_timeout(n); if (timeout) ret = false; } @@ -6367,7 +6367,7 @@ static void busy_poll_stop(struct napi_struct *napi, void *have_poll_lock, if (flags & NAPI_F_PREFER_BUSY_POLL) { napi->defer_hard_irqs_count = napi_get_defer_hard_irqs(napi); - timeout = READ_ONCE(napi->dev->gro_flush_timeout); + timeout = napi_get_gro_flush_timeout(napi); if (napi->defer_hard_irqs_count && timeout) { hrtimer_start(&napi->timer, ns_to_ktime(timeout), HRTIMER_MODE_REL_PINNED); skip_schedule = true; @@ -6649,6 +6649,7 @@ void netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi, hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED); napi->timer.function = napi_watchdog; napi_set_defer_hard_irqs(napi, READ_ONCE(dev->napi_defer_hard_irqs)); + napi_set_gro_flush_timeout(napi, READ_ONCE(dev->gro_flush_timeout)); init_gro_hash(napi); napi->skb = NULL; INIT_LIST_HEAD(&napi->rx_list); @@ -11033,7 +11034,7 @@ void netdev_sw_irq_coalesce_default_on(struct net_device *dev) WARN_ON(dev->reg_state == NETREG_REGISTERED); if (!IS_ENABLED(CONFIG_PREEMPT_RT)) { - dev->gro_flush_timeout = 20000; + netdev_set_gro_flush_timeout(dev, 20000); netdev_set_defer_hard_irqs(dev, 1); } } @@ -11982,7 +11983,6 @@ static void __init net_dev_struct_check(void) CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, ifindex); CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, real_num_rx_queues); CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, _rx); - CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, gro_flush_timeout); CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, gro_max_size); CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, gro_ipv4_max_size); CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, rx_handler); @@ -11995,7 +11995,7 @@ static void __init net_dev_struct_check(void) CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, tcx_ingress); #endif CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, napi_storage); - CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_rx, 108); + CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_rx, 100); } /* diff --git a/net/core/dev.h b/net/core/dev.h index 2584a7de189f..f33d7bcb923f 100644 --- a/net/core/dev.h +++ b/net/core/dev.h @@ -178,6 +178,49 @@ static inline void netdev_set_defer_hard_irqs(struct net_device *netdev, napi_set_defer_hard_irqs(napi, defer); } +/** + * napi_get_gro_flush_timeout - get the gro_flush_timeout + * @n: napi struct to get the gro_flush_timeout from + * + * Return: the per-NAPI value of the gro_flush_timeout field. + */ +static inline unsigned long napi_get_gro_flush_timeout(const struct napi_struct *n) +{ + if (n->napi_storage) + return READ_ONCE(n->napi_storage->gro_flush_timeout); + else + return READ_ONCE(n->dev->napi_defer_hard_irqs); +} + +/** + * napi_set_gro_flush_timeout - set the gro_flush_timeout for a napi + * @n: napi struct to set the gro_flush_timeout + * @timeout: timeout value to set + * + * napi_set_gro_flush_timeout sets the per-NAPI gro_flush_timeout + */ +static inline void napi_set_gro_flush_timeout(struct napi_struct *n, + unsigned long timeout) +{ + if (n->napi_storage) + WRITE_ONCE(n->napi_storage->gro_flush_timeout, timeout); +} + +/** + * netdev_set_gro_flush_timeout - set gro_flush_timeout for all NAPIs of a netdev + * @netdev: the net_device for which all NAPIs will have their gro_flush_timeout set + * @timeout: the timeout value to set + */ +static inline void netdev_set_gro_flush_timeout(struct net_device *netdev, + unsigned long timeout) +{ + struct napi_struct *napi; + + WRITE_ONCE(netdev->gro_flush_timeout, timeout); + list_for_each_entry(napi, &netdev->napi_list, dev_list) + napi_set_gro_flush_timeout(napi, timeout); +} + int rps_cpumask_housekeeping(struct cpumask *mask); #if defined(CONFIG_DEBUG_NET) && defined(CONFIG_BPF_SYSCALL) diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index 0a0bbbfb39b4..daa32b5a6623 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -409,7 +409,7 @@ NETDEVICE_SHOW_RW(tx_queue_len, fmt_dec); static int change_gro_flush_timeout(struct net_device *dev, unsigned long val) { - WRITE_ONCE(dev->gro_flush_timeout, val); + netdev_set_gro_flush_timeout(dev, val); return 0; } diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c index f1e505ad069f..68ec8265567d 100644 --- a/net/core/netdev-genl.c +++ b/net/core/netdev-genl.c @@ -161,6 +161,7 @@ netdev_nl_napi_fill_one(struct sk_buff *rsp, struct napi_struct *napi, const struct genl_info *info) { int napi_defer_hard_irqs; + unsigned long gro_flush_timeout; void *hdr; pid_t pid; @@ -196,6 +197,10 @@ netdev_nl_napi_fill_one(struct sk_buff *rsp, struct napi_struct *napi, if (nla_put_s32(rsp, NETDEV_A_NAPI_DEFER_HARD_IRQS, napi_defer_hard_irqs)) goto nla_put_failure; + gro_flush_timeout = napi_get_gro_flush_timeout(napi); + if (nla_put_uint(rsp, NETDEV_A_NAPI_GRO_FLUSH_TIMEOUT, gro_flush_timeout)) + goto nla_put_failure; + genlmsg_end(rsp, hdr); return 0; diff --git a/tools/include/uapi/linux/netdev.h b/tools/include/uapi/linux/netdev.h index 43bb1aad9611..b088a34e9254 100644 --- a/tools/include/uapi/linux/netdev.h +++ b/tools/include/uapi/linux/netdev.h @@ -122,6 +122,7 @@ enum { NETDEV_A_NAPI_IRQ, NETDEV_A_NAPI_PID, NETDEV_A_NAPI_DEFER_HARD_IRQS, + NETDEV_A_NAPI_GRO_FLUSH_TIMEOUT, __NETDEV_A_NAPI_MAX, NETDEV_A_NAPI_MAX = (__NETDEV_A_NAPI_MAX - 1) -- 2.25.1