| Message ID | 20230919135517.286766-1-yajun.deng@linux.dev (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net-next,v5] net/core: Introduce netdev_core_stats_inc() for trace | expand |
Hi, MAINTAINERS, Kindly ping... Thanks On 2023/9/19 21:55, Yajun Deng wrote: > 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. > > Introduce netdev_core_stats_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> > Suggested-by: Alexander Lobakin <aleksander.lobakin@intel.com> > --- > v5: Access the per cpu pointer before reach the relevant offset. > v4: Introduce netdev_core_stats_inc() instead of export dev_core_stats_*_inc() > 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 | 21 ++++----------------- > net/core/dev.c | 26 ++++++++++++++++++++++++-- > 2 files changed, 28 insertions(+), 19 deletions(-) > > diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h > index db3d8429d50d..4c258d44c7d2 100644 > --- a/include/linux/netdevice.h > +++ b/include/linux/netdevice.h > @@ -4001,32 +4001,19 @@ 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); > -} > +void netdev_core_stats_inc(struct net_device *dev, u32 offset); > > #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); \ > + netdev_core_stats_inc(dev, \ > + offsetof(struct net_device_core_stats, 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) > +#undef DEV_CORE_STATS_INC > > static __always_inline int ____dev_forward_skb(struct net_device *dev, > struct sk_buff *skb, > diff --git a/net/core/dev.c b/net/core/dev.c > index 606a366cc209..4bc0161bc0d6 100644 > --- a/net/core/dev.c > +++ b/net/core/dev.c > @@ -10497,7 +10497,8 @@ 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; > > @@ -10510,7 +10511,28 @@ 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 *netdev_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); > +} > + > +void netdev_core_stats_inc(struct net_device *dev, u32 offset) > +{ > + struct net_device_core_stats __percpu *p; > + > + p = netdev_core_stats(dev); > + if (p) > + (*(unsigned long *)((void *)this_cpu_ptr(p) + offset))++; > +} > +EXPORT_SYMBOL_GPL(netdev_core_stats_inc); > > /** > * dev_get_stats - get network device statistics
On Tue, 2023-09-19 at 21:55 +0800, Yajun Deng wrote: > 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. > > Introduce netdev_core_stats_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> > Suggested-by: Alexander Lobakin <aleksander.lobakin@intel.com> > --- > v5: Access the per cpu pointer before reach the relevant offset. > v4: Introduce netdev_core_stats_inc() instead of export dev_core_stats_*_inc() > 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 | 21 ++++----------------- > net/core/dev.c | 26 ++++++++++++++++++++++++-- > 2 files changed, 28 insertions(+), 19 deletions(-) > > diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h > index db3d8429d50d..4c258d44c7d2 100644 > --- a/include/linux/netdevice.h > +++ b/include/linux/netdevice.h > @@ -4001,32 +4001,19 @@ 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); > -} > +void netdev_core_stats_inc(struct net_device *dev, u32 offset); > > #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); \ > + netdev_core_stats_inc(dev, \ > + offsetof(struct net_device_core_stats, 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) > +#undef DEV_CORE_STATS_INC > > static __always_inline int ____dev_forward_skb(struct net_device *dev, > struct sk_buff *skb, > diff --git a/net/core/dev.c b/net/core/dev.c > index 606a366cc209..4bc0161bc0d6 100644 > --- a/net/core/dev.c > +++ b/net/core/dev.c > @@ -10497,7 +10497,8 @@ 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; > > @@ -10510,7 +10511,28 @@ 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 *netdev_core_stats( > + struct net_device *dev) I'm sorry for the delayed feedback - conference and traveling in the way. It looks like the 'inline' keyword above is a left-over of a previous revision? The compiler should generate the same code even without it, right? If so, it should be better drop it. Cheers, Paolo
On 2023/9/28 16:23, Paolo Abeni wrote: > On Tue, 2023-09-19 at 21:55 +0800, Yajun Deng wrote: >> 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. >> >> Introduce netdev_core_stats_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> >> Suggested-by: Alexander Lobakin <aleksander.lobakin@intel.com> >> --- >> v5: Access the per cpu pointer before reach the relevant offset. >> v4: Introduce netdev_core_stats_inc() instead of export dev_core_stats_*_inc() >> 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 | 21 ++++----------------- >> net/core/dev.c | 26 ++++++++++++++++++++++++-- >> 2 files changed, 28 insertions(+), 19 deletions(-) >> >> diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h >> index db3d8429d50d..4c258d44c7d2 100644 >> --- a/include/linux/netdevice.h >> +++ b/include/linux/netdevice.h >> @@ -4001,32 +4001,19 @@ 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); >> -} >> +void netdev_core_stats_inc(struct net_device *dev, u32 offset); >> >> #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); \ >> + netdev_core_stats_inc(dev, \ >> + offsetof(struct net_device_core_stats, 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) >> +#undef DEV_CORE_STATS_INC >> >> static __always_inline int ____dev_forward_skb(struct net_device *dev, >> struct sk_buff *skb, >> diff --git a/net/core/dev.c b/net/core/dev.c >> index 606a366cc209..4bc0161bc0d6 100644 >> --- a/net/core/dev.c >> +++ b/net/core/dev.c >> @@ -10497,7 +10497,8 @@ 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; >> >> @@ -10510,7 +10511,28 @@ 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 *netdev_core_stats( >> + struct net_device *dev) > I'm sorry for the delayed feedback - conference and traveling in the > way. > > It looks like the 'inline' keyword above is a left-over of a previous > revision? The compiler should generate the same code even without it, > right? If so, it should be better drop it. If so, should I merge netdev_core_stats and netdev_core_stats_inc together, as it didn't called by others. Like: void netdev_core_stats_inc(struct net_device *dev, u32 offset) { /* 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 (unlikely(!p)) p = netdev_core_stats_alloc(dev); if (p) (*(unsigned long *)((void *)this_cpu_ptr(p) + offset))++; } EXPORT_SYMBOL_GPL(netdev_core_stats_inc); > > Cheers, > > Paolo >
On Thu, 2023-09-28 at 17:21 +0800, Yajun Deng wrote: > On 2023/9/28 16:23, Paolo Abeni wrote: > > On Tue, 2023-09-19 at 21:55 +0800, Yajun Deng wrote: > > > 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. > > > > > > Introduce netdev_core_stats_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> > > > Suggested-by: Alexander Lobakin <aleksander.lobakin@intel.com> > > > --- > > > v5: Access the per cpu pointer before reach the relevant offset. > > > v4: Introduce netdev_core_stats_inc() instead of export dev_core_stats_*_inc() > > > 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 | 21 ++++----------------- > > > net/core/dev.c | 26 ++++++++++++++++++++++++-- > > > 2 files changed, 28 insertions(+), 19 deletions(-) > > > > > > diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h > > > index db3d8429d50d..4c258d44c7d2 100644 > > > --- a/include/linux/netdevice.h > > > +++ b/include/linux/netdevice.h > > > @@ -4001,32 +4001,19 @@ 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); > > > -} > > > +void netdev_core_stats_inc(struct net_device *dev, u32 offset); > > > > > > #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); \ > > > + netdev_core_stats_inc(dev, \ > > > + offsetof(struct net_device_core_stats, 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) > > > +#undef DEV_CORE_STATS_INC > > > > > > static __always_inline int ____dev_forward_skb(struct net_device *dev, > > > struct sk_buff *skb, > > > diff --git a/net/core/dev.c b/net/core/dev.c > > > index 606a366cc209..4bc0161bc0d6 100644 > > > --- a/net/core/dev.c > > > +++ b/net/core/dev.c > > > @@ -10497,7 +10497,8 @@ 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; > > > > > > @@ -10510,7 +10511,28 @@ 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 *netdev_core_stats( > > > + struct net_device *dev) > > I'm sorry for the delayed feedback - conference and traveling in the > > way. > > > > It looks like the 'inline' keyword above is a left-over of a previous > > revision? The compiler should generate the same code even without it, > > right? If so, it should be better drop it. > > > If so, should I merge netdev_core_stats and netdev_core_stats_inc > together, as it didn't called by others. Like: > > void netdev_core_stats_inc(struct net_device *dev, u32 offset) > { > /* 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 (unlikely(!p)) > p = netdev_core_stats_alloc(dev); > > if (p) > (*(unsigned long *)((void *)this_cpu_ptr(p) + offset))++; > } > EXPORT_SYMBOL_GPL(netdev_core_stats_inc); Makes sense to me. I initially thought the code would be more readable with 2 separate functions, but the above LGTM. Cheers, Paolo
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index db3d8429d50d..4c258d44c7d2 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -4001,32 +4001,19 @@ 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); -} +void netdev_core_stats_inc(struct net_device *dev, u32 offset); #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); \ + netdev_core_stats_inc(dev, \ + offsetof(struct net_device_core_stats, 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) +#undef DEV_CORE_STATS_INC static __always_inline int ____dev_forward_skb(struct net_device *dev, struct sk_buff *skb, diff --git a/net/core/dev.c b/net/core/dev.c index 606a366cc209..4bc0161bc0d6 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -10497,7 +10497,8 @@ 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; @@ -10510,7 +10511,28 @@ 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 *netdev_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); +} + +void netdev_core_stats_inc(struct net_device *dev, u32 offset) +{ + struct net_device_core_stats __percpu *p; + + p = netdev_core_stats(dev); + if (p) + (*(unsigned long *)((void *)this_cpu_ptr(p) + offset))++; +} +EXPORT_SYMBOL_GPL(netdev_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. Introduce netdev_core_stats_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> Suggested-by: Alexander Lobakin <aleksander.lobakin@intel.com> --- v5: Access the per cpu pointer before reach the relevant offset. v4: Introduce netdev_core_stats_inc() instead of export dev_core_stats_*_inc() 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 | 21 ++++----------------- net/core/dev.c | 26 ++++++++++++++++++++++++-- 2 files changed, 28 insertions(+), 19 deletions(-)