| Message ID | 20230914023718.3854545-1-yajun.deng@linux.dev (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net-next,v3] net/core: Export dev_core_stats_*_inc() | expand |
From: Yajun Deng <yajun.deng@linux.dev> Date: Thu, 14 Sep 2023 10:37:18 +0800 > Although there is a kfree_skb_reason() helper function that can be used to > find the reason why this skb is dropped, but most callers didn't increase > one of rx_dropped, tx_dropped, rx_nohandler and rx_otherhost_dropped. > > For the users, people are more concerned about why the dropped in ip > is increasing. So we can export dev_core_stats_rx_dropped_inc sets, > which users would trace them know why rx_dropped is increasing. > > Export dev_core_stats_{rx_dropped, tx_dropped, rx_nohandler, > rx_otherhost_dropped}_inc for trace. Also, move dev_core_stats() > and netdev_core_stats_alloc() to dev.c, as they are not called > externally. I'd like to hear some arguments against having them static inlines + one external that I proposed earlier. > > Signed-off-by: Yajun Deng <yajun.deng@linux.dev> > --- > v3: __cold should be added to the netdev_core_stats_alloc(). > v2: use __cold instead of inline in dev_core_stats(). > v1: https://lore.kernel.org/netdev/20230911082016.3694700-1-yajun.deng@linux.dev/ ...as it's not at least mentioned here in the changelog. [...] > diff --git a/net/core/dev.c b/net/core/dev.c > index ccff2b6ef958..98592e4c1df0 100644 > --- a/net/core/dev.c > +++ b/net/core/dev.c > @@ -10475,7 +10475,7 @@ void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64, > } > EXPORT_SYMBOL(netdev_stats_to_stats64); > > -struct net_device_core_stats __percpu *netdev_core_stats_alloc(struct net_device *dev) > +static __cold struct net_device_core_stats __percpu *netdev_core_stats_alloc(struct net_device *dev) This is way over 79/80 chars, break the line before "netdev_". > { > struct net_device_core_stats __percpu *p; > > @@ -10488,7 +10488,35 @@ struct net_device_core_stats __percpu *netdev_core_stats_alloc(struct net_device > /* This READ_ONCE() pairs with the cmpxchg() above */ > return READ_ONCE(dev->core_stats); > } > -EXPORT_SYMBOL(netdev_core_stats_alloc); > + > +static inline struct net_device_core_stats __percpu *dev_core_stats(struct net_device *dev) Same for the line length. Also notice that now some of the functions you touch have "dev_" prefix, others have "netdev_", I'd probably take a look into unifying this. (note for the maintainers that it would be probably better to leave explicit "inline" here, but no bloat-o-meter was provided by the author, so I can't say anything for sure) > +{ > + /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */ > + struct net_device_core_stats __percpu *p = READ_ONCE(dev->core_stats); > + > + if (likely(p)) > + return p; > + > + return netdev_core_stats_alloc(dev); > +} [...] Thanks, Olek
On 2023/9/14 23:22, Alexander Lobakin wrote: > From: Yajun Deng <yajun.deng@linux.dev> > Date: Thu, 14 Sep 2023 10:37:18 +0800 > >> Although there is a kfree_skb_reason() helper function that can be used to >> find the reason why this skb is dropped, but most callers didn't increase >> one of rx_dropped, tx_dropped, rx_nohandler and rx_otherhost_dropped. >> >> For the users, people are more concerned about why the dropped in ip >> is increasing. So we can export dev_core_stats_rx_dropped_inc sets, >> which users would trace them know why rx_dropped is increasing. >> >> Export dev_core_stats_{rx_dropped, tx_dropped, rx_nohandler, >> rx_otherhost_dropped}_inc for trace. Also, move dev_core_stats() >> and netdev_core_stats_alloc() to dev.c, as they are not called >> externally. > I'd like to hear some arguments against having them static inlines + one > external that I proposed earlier. I'd like to hear suggestions from the maintainers. If the maintainers have no objections, I'd like to use your approach. >> Signed-off-by: Yajun Deng <yajun.deng@linux.dev> >> --- >> v3: __cold should be added to the netdev_core_stats_alloc(). >> v2: use __cold instead of inline in dev_core_stats(). >> v1: https://lore.kernel.org/netdev/20230911082016.3694700-1-yajun.deng@linux.dev/ > ...as it's not at least mentioned here in the changelog. > > [...] > >> diff --git a/net/core/dev.c b/net/core/dev.c >> index ccff2b6ef958..98592e4c1df0 100644 >> --- a/net/core/dev.c >> +++ b/net/core/dev.c >> @@ -10475,7 +10475,7 @@ void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64, >> } >> EXPORT_SYMBOL(netdev_stats_to_stats64); >> >> -struct net_device_core_stats __percpu *netdev_core_stats_alloc(struct net_device *dev) >> +static __cold struct net_device_core_stats __percpu *netdev_core_stats_alloc(struct net_device *dev) > This is way over 79/80 chars, break the line before "netdev_". Okay. > >> { >> struct net_device_core_stats __percpu *p; >> >> @@ -10488,7 +10488,35 @@ struct net_device_core_stats __percpu *netdev_core_stats_alloc(struct net_device >> /* This READ_ONCE() pairs with the cmpxchg() above */ >> return READ_ONCE(dev->core_stats); >> } >> -EXPORT_SYMBOL(netdev_core_stats_alloc); >> + >> +static inline struct net_device_core_stats __percpu *dev_core_stats(struct net_device *dev) > Same for the line length. > Also notice that now some of the functions you touch have "dev_" prefix, > others have "netdev_", I'd probably take a look into unifying this. Okay, I'll unify with the "netdev_" prefix. > (note for the maintainers that it would be probably better to leave > explicit "inline" here, but no bloat-o-meter was provided by the > author, so I can't say anything for sure) > >> +{ >> + /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */ >> + struct net_device_core_stats __percpu *p = READ_ONCE(dev->core_stats); >> + >> + if (likely(p)) >> + return p; >> + >> + return netdev_core_stats_alloc(dev); >> +} > [...] > > Thanks, > Olek
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 0896aaa91dd7..879b01c85ba4 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3954,6 +3954,11 @@ int dev_forward_skb_nomtu(struct net_device *dev, struct sk_buff *skb); bool is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb); +void dev_core_stats_rx_dropped_inc(struct net_device *dev); +void dev_core_stats_tx_dropped_inc(struct net_device *dev); +void dev_core_stats_rx_nohandler_inc(struct net_device *dev); +void dev_core_stats_rx_otherhost_dropped_inc(struct net_device *dev); + static __always_inline bool __is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb, const bool check_mtu) @@ -3980,33 +3985,6 @@ static __always_inline bool __is_skb_forwardable(const struct net_device *dev, return false; } -struct net_device_core_stats __percpu *netdev_core_stats_alloc(struct net_device *dev); - -static inline struct net_device_core_stats __percpu *dev_core_stats(struct net_device *dev) -{ - /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */ - struct net_device_core_stats __percpu *p = READ_ONCE(dev->core_stats); - - if (likely(p)) - return p; - - return netdev_core_stats_alloc(dev); -} - -#define DEV_CORE_STATS_INC(FIELD) \ -static inline void dev_core_stats_##FIELD##_inc(struct net_device *dev) \ -{ \ - struct net_device_core_stats __percpu *p; \ - \ - p = dev_core_stats(dev); \ - if (p) \ - this_cpu_inc(p->FIELD); \ -} -DEV_CORE_STATS_INC(rx_dropped) -DEV_CORE_STATS_INC(tx_dropped) -DEV_CORE_STATS_INC(rx_nohandler) -DEV_CORE_STATS_INC(rx_otherhost_dropped) - static __always_inline int ____dev_forward_skb(struct net_device *dev, struct sk_buff *skb, const bool check_mtu) diff --git a/net/core/dev.c b/net/core/dev.c index ccff2b6ef958..98592e4c1df0 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -10475,7 +10475,7 @@ void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64, } EXPORT_SYMBOL(netdev_stats_to_stats64); -struct net_device_core_stats __percpu *netdev_core_stats_alloc(struct net_device *dev) +static __cold struct net_device_core_stats __percpu *netdev_core_stats_alloc(struct net_device *dev) { struct net_device_core_stats __percpu *p; @@ -10488,7 +10488,35 @@ struct net_device_core_stats __percpu *netdev_core_stats_alloc(struct net_device /* This READ_ONCE() pairs with the cmpxchg() above */ return READ_ONCE(dev->core_stats); } -EXPORT_SYMBOL(netdev_core_stats_alloc); + +static inline struct net_device_core_stats __percpu *dev_core_stats(struct net_device *dev) +{ + /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */ + struct net_device_core_stats __percpu *p = READ_ONCE(dev->core_stats); + + if (likely(p)) + return p; + + return netdev_core_stats_alloc(dev); +} + +#define DEV_CORE_STATS_INC(FIELD) \ +void dev_core_stats_##FIELD##_inc(struct net_device *dev) \ +{ \ + struct net_device_core_stats __percpu *p; \ + \ + p = dev_core_stats(dev); \ + if (p) \ + this_cpu_inc(p->FIELD); \ +} \ +EXPORT_SYMBOL(dev_core_stats_##FIELD##_inc) + +DEV_CORE_STATS_INC(rx_dropped); +DEV_CORE_STATS_INC(tx_dropped); +DEV_CORE_STATS_INC(rx_nohandler); +DEV_CORE_STATS_INC(rx_otherhost_dropped); + +#undef DEV_CORE_STATS_INC /** * dev_get_stats - get network device statistics
Although there is a kfree_skb_reason() helper function that can be used to find the reason why this skb is dropped, but most callers didn't increase one of rx_dropped, tx_dropped, rx_nohandler and rx_otherhost_dropped. For the users, people are more concerned about why the dropped in ip is increasing. So we can export dev_core_stats_rx_dropped_inc sets, which users would trace them know why rx_dropped is increasing. Export dev_core_stats_{rx_dropped, tx_dropped, rx_nohandler, rx_otherhost_dropped}_inc for trace. Also, move dev_core_stats() and netdev_core_stats_alloc() to dev.c, as they are not called externally. Signed-off-by: Yajun Deng <yajun.deng@linux.dev> --- v3: __cold should be added to the netdev_core_stats_alloc(). v2: use __cold instead of inline in dev_core_stats(). v1: https://lore.kernel.org/netdev/20230911082016.3694700-1-yajun.deng@linux.dev/ --- include/linux/netdevice.h | 32 +++++--------------------------- net/core/dev.c | 32 ++++++++++++++++++++++++++++++-- 2 files changed, 35 insertions(+), 29 deletions(-)