From 8ee2267ad33e0ba021e9dd9b437f773906cd99d6 Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Tue, 29 Sep 2020 11:15:52 +0300 Subject: [PATCH] drop_monitor: Convert to using devlink tracepoint Convert drop monitor to use the recently introduced 'devlink_trap_report' tracepoint instead of having devlink call into drop monitor. This is both consistent with software originated drops ('kfree_skb' tracepoint) and also allows drop monitor to be built as a module and still report hardware originated drops. Signed-off-by: Ido Schimmel Reviewed-by: Jiri Pirko Signed-off-by: David S. Miller --- MAINTAINERS | 1 - include/net/drop_monitor.h | 36 ----------------------- net/Kconfig | 1 - net/core/devlink.c | 24 --------------- net/core/drop_monitor.c | 60 ++++++++++++++++++++++++++------------ 5 files changed, 42 insertions(+), 80 deletions(-) delete mode 100644 include/net/drop_monitor.h diff --git a/MAINTAINERS b/MAINTAINERS index 42c69d2eeece..c1e946606dce 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -12065,7 +12065,6 @@ M: Neil Horman L: netdev@vger.kernel.org S: Maintained W: https://fedorahosted.org/dropwatch/ -F: include/net/drop_monitor.h F: include/uapi/linux/net_dropmon.h F: net/core/drop_monitor.c diff --git a/include/net/drop_monitor.h b/include/net/drop_monitor.h deleted file mode 100644 index 3f5b6ddb3179..000000000000 --- a/include/net/drop_monitor.h +++ /dev/null @@ -1,36 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0-only */ - -#ifndef _NET_DROP_MONITOR_H_ -#define _NET_DROP_MONITOR_H_ - -#include -#include -#include -#include - -/** - * struct net_dm_hw_metadata - Hardware-supplied packet metadata. - * @trap_group_name: Hardware trap group name. - * @trap_name: Hardware trap name. - * @input_dev: Input netdevice. - * @fa_cookie: Flow action user cookie. - */ -struct net_dm_hw_metadata { - const char *trap_group_name; - const char *trap_name; - struct net_device *input_dev; - const struct flow_action_cookie *fa_cookie; -}; - -#if IS_REACHABLE(CONFIG_NET_DROP_MONITOR) -void net_dm_hw_report(struct sk_buff *skb, - const struct net_dm_hw_metadata *hw_metadata); -#else -static inline void -net_dm_hw_report(struct sk_buff *skb, - const struct net_dm_hw_metadata *hw_metadata) -{ -} -#endif - -#endif /* _NET_DROP_MONITOR_H_ */ diff --git a/net/Kconfig b/net/Kconfig index 3831206977a1..d6567162c1cf 100644 --- a/net/Kconfig +++ b/net/Kconfig @@ -434,7 +434,6 @@ config NET_SOCK_MSG config NET_DEVLINK bool default n - imply NET_DROP_MONITOR config PAGE_POOL bool diff --git a/net/core/devlink.c b/net/core/devlink.c index c0f300507c37..2ea9fdc0df2d 100644 --- a/net/core/devlink.c +++ b/net/core/devlink.c @@ -27,7 +27,6 @@ #include #include #include -#include #define CREATE_TRACE_POINTS #include @@ -9261,24 +9260,6 @@ devlink_trap_stats_update(struct devlink_stats __percpu *trap_stats, u64_stats_update_end(&stats->syncp); } -static void -devlink_trap_report_metadata_fill(struct net_dm_hw_metadata *hw_metadata, - const struct devlink_trap_item *trap_item, - struct devlink_port *in_devlink_port, - const struct flow_action_cookie *fa_cookie) -{ - struct devlink_trap_group_item *group_item = trap_item->group_item; - - hw_metadata->trap_group_name = group_item->group->name; - hw_metadata->trap_name = trap_item->trap->name; - hw_metadata->fa_cookie = fa_cookie; - - spin_lock(&in_devlink_port->type_lock); - if (in_devlink_port->type == DEVLINK_PORT_TYPE_ETH) - hw_metadata->input_dev = in_devlink_port->type_dev; - spin_unlock(&in_devlink_port->type_lock); -} - static void devlink_trap_report_metadata_set(struct devlink_trap_metadata *metadata, const struct devlink_trap_item *trap_item, @@ -9309,7 +9290,6 @@ void devlink_trap_report(struct devlink *devlink, struct sk_buff *skb, { struct devlink_trap_item *trap_item = trap_ctx; - struct net_dm_hw_metadata hw_metadata = {}; devlink_trap_stats_update(trap_item->stats, skb->len); devlink_trap_stats_update(trap_item->group_item->stats, skb->len); @@ -9321,10 +9301,6 @@ void devlink_trap_report(struct devlink *devlink, struct sk_buff *skb, if (trap_item->trap->type == DEVLINK_TRAP_TYPE_CONTROL) return; - devlink_trap_report_metadata_fill(&hw_metadata, trap_item, - in_devlink_port, fa_cookie); - net_dm_hw_report(skb, &hw_metadata); - if (trace_devlink_trap_report_enabled()) { struct devlink_trap_metadata metadata = {}; diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c index 03aba582c0b9..c14278fd6405 100644 --- a/net/core/drop_monitor.c +++ b/net/core/drop_monitor.c @@ -26,7 +26,6 @@ #include #include #include -#include #include #include #include @@ -34,6 +33,7 @@ #include #include +#include #include @@ -108,6 +108,13 @@ static enum net_dm_alert_mode net_dm_alert_mode = NET_DM_ALERT_MODE_SUMMARY; static u32 net_dm_trunc_len; static u32 net_dm_queue_len = 1000; +struct net_dm_hw_metadata { + const char *trap_group_name; + const char *trap_name; + struct net_device *input_dev; + const struct flow_action_cookie *fa_cookie; +}; + struct net_dm_alert_ops { void (*kfree_skb_probe)(void *ignore, struct sk_buff *skb, void *location); @@ -1129,25 +1136,32 @@ static const struct net_dm_alert_ops *net_dm_alert_ops_arr[] = { [NET_DM_ALERT_MODE_PACKET] = &net_dm_alert_packet_ops, }; -void net_dm_hw_report(struct sk_buff *skb, - const struct net_dm_hw_metadata *hw_metadata) +#if IS_ENABLED(CONFIG_NET_DEVLINK) +static int net_dm_hw_probe_register(const struct net_dm_alert_ops *ops) { - rcu_read_lock(); - - if (!monitor_hw) - goto out; - - net_dm_alert_ops_arr[net_dm_alert_mode]->hw_probe(skb, hw_metadata); - -out: - rcu_read_unlock(); + return register_trace_devlink_trap_report(ops->hw_trap_probe, NULL); } -EXPORT_SYMBOL_GPL(net_dm_hw_report); + +static void net_dm_hw_probe_unregister(const struct net_dm_alert_ops *ops) +{ + unregister_trace_devlink_trap_report(ops->hw_trap_probe, NULL); + tracepoint_synchronize_unregister(); +} +#else +static int net_dm_hw_probe_register(const struct net_dm_alert_ops *ops) +{ + return -EOPNOTSUPP; +} + +static void net_dm_hw_probe_unregister(const struct net_dm_alert_ops *ops) +{ +} +#endif static int net_dm_hw_monitor_start(struct netlink_ext_ack *extack) { const struct net_dm_alert_ops *ops; - int cpu; + int cpu, rc; if (monitor_hw) { NL_SET_ERR_MSG_MOD(extack, "Hardware monitoring already enabled"); @@ -1171,13 +1185,24 @@ static int net_dm_hw_monitor_start(struct netlink_ext_ack *extack) kfree(hw_entries); } + rc = net_dm_hw_probe_register(ops); + if (rc) { + NL_SET_ERR_MSG_MOD(extack, "Failed to connect probe to devlink_trap_probe() tracepoint"); + goto err_module_put; + } + monitor_hw = true; return 0; + +err_module_put: + module_put(THIS_MODULE); + return rc; } static void net_dm_hw_monitor_stop(struct netlink_ext_ack *extack) { + const struct net_dm_alert_ops *ops; int cpu; if (!monitor_hw) { @@ -1185,12 +1210,11 @@ static void net_dm_hw_monitor_stop(struct netlink_ext_ack *extack) return; } + ops = net_dm_alert_ops_arr[net_dm_alert_mode]; + monitor_hw = false; - /* After this call returns we are guaranteed that no CPU is processing - * any hardware drops. - */ - synchronize_rcu(); + net_dm_hw_probe_unregister(ops); for_each_possible_cpu(cpu) { struct per_cpu_dm_data *hw_data = &per_cpu(dm_hw_cpu_data, cpu);