| Message ID | 5bb71143-0dac-c413-7e97-50eed8a57862@gmail.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Delegated to: | Johannes Berg |
| Headers | show |
| Series | net: add and use function dev_fetch_sw_netstats for fetching pcpu_sw_netstats | expand |
On Sun, 11 Oct 2020 21:36:43 +0200 Heiner Kallweit <hkallweit1@gmail.com> wrote: > +void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s, > + struct pcpu_sw_netstats __percpu *netstats) netstats is unmodified, should it be const? > +{ > + int cpu; > + > + if (IS_ERR_OR_NULL(netstats)) > + return; Any code calling this with a null pointer is broken/buggy, please don't ignore that.
On 11.10.2020 21:54, Stephen Hemminger wrote: > On Sun, 11 Oct 2020 21:36:43 +0200 > Heiner Kallweit <hkallweit1@gmail.com> wrote: > >> +void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s, >> + struct pcpu_sw_netstats __percpu *netstats) > > netstats is unmodified, should it be const? > >> +{ >> + int cpu; >> + >> + if (IS_ERR_OR_NULL(netstats)) >> + return; > > Any code calling this with a null pointer is broken/buggy, please don't > ignore that. > Thanks, I'll consider both points in a v2.
On Sun, 11 Oct 2020 21:36:43 +0200 Heiner Kallweit wrote: > In several places the same code is used to populate rtnl_link_stats64 > fields with data from pcpu_sw_netstats. Therefore factor out this code > to a new function dev_fetch_sw_netstats(). > > Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> > +/** > + * dev_fetch_sw_netstats - get per-cpu network device statistics > + * @s: place to store stats > + * @netstats: per-cpu network stats to read from > + * > + * Read per-cpu network statistics and populate the related fields in s. in @s? > + */ > +void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s, > + struct pcpu_sw_netstats __percpu *netstats) > +} > +EXPORT_SYMBOL(dev_fetch_sw_netstats); Your pick, but _GPL would be fine too even if most exports here are non-GPL-exclusive.
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index a0df43b13..ca4736349 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -4495,6 +4495,8 @@ struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, struct rtnl_link_stats64 *storage); void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64, const struct net_device_stats *netdev_stats); +void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s, + struct pcpu_sw_netstats __percpu *netstats); extern int netdev_max_backlog; extern int netdev_tstamp_prequeue; diff --git a/net/core/dev.c b/net/core/dev.c index 7d18560b2..ba91bf16b 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -10323,6 +10323,42 @@ struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, } EXPORT_SYMBOL(dev_get_stats); +/** + * dev_fetch_sw_netstats - get per-cpu network device statistics + * @s: place to store stats + * @netstats: per-cpu network stats to read from + * + * Read per-cpu network statistics and populate the related fields in s. + */ +void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s, + struct pcpu_sw_netstats __percpu *netstats) +{ + int cpu; + + if (IS_ERR_OR_NULL(netstats)) + return; + + for_each_possible_cpu(cpu) { + struct pcpu_sw_netstats *stats, tmp; + unsigned int start; + + stats = per_cpu_ptr(netstats, cpu); + do { + start = u64_stats_fetch_begin_irq(&stats->syncp); + tmp.rx_packets = stats->rx_packets; + tmp.rx_bytes = stats->rx_bytes; + tmp.tx_packets = stats->tx_packets; + tmp.tx_bytes = stats->tx_bytes; + } while (u64_stats_fetch_retry_irq(&stats->syncp, start)); + + s->rx_packets += tmp.rx_packets; + s->rx_bytes += tmp.rx_bytes; + s->tx_packets += tmp.tx_packets; + s->tx_bytes += tmp.tx_bytes; + } +} +EXPORT_SYMBOL(dev_fetch_sw_netstats); + struct netdev_queue *dev_ingress_queue_create(struct net_device *dev) { struct netdev_queue *queue = dev_ingress_queue(dev);
In several places the same code is used to populate rtnl_link_stats64 fields with data from pcpu_sw_netstats. Therefore factor out this code to a new function dev_fetch_sw_netstats(). Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> --- include/linux/netdevice.h | 2 ++ net/core/dev.c | 36 ++++++++++++++++++++++++++++++++++++ 2 files changed, 38 insertions(+)