| Message ID | 1446486818-26166-1-git-send-email-jarod@redhat.com |
|---|---|
| State | Superseded, archived |
| Delegated to: | David Miller |
| Headers | show |
On 11/02/2015 09:53 AM, Jarod Wilson wrote: > There are some netdev features, which when disabled on an upper device, > such as a bonding master or a bridge, must be disabled and cannot be > re-enabled on underlying devices. > > This is a rework of an earlier more heavy-handed appraoch, which simply > disables and prevents re-enabling of netdev features listed in a new > define in include/net/netdev_features.h, NETIF_F_UPPER_DISABLES. Any upper > device that disables a flag in that feature mask, the disabling will > propagate down the stack, and any lower device that has any upper device > with one of those flags disabled should not be able to enable said flag. > > Initially, only LRO is included for proof of concept, and because this > code effectively does the same thing as dev_disable_lro(), though it will > also activate from the ethtool path, which was one of the goals here. > > [root@dell-per730-01 ~]# ethtool -k bond0 |grep large > large-receive-offload: on > [root@dell-per730-01 ~]# ethtool -k p5p1 |grep large > large-receive-offload: on > [root@dell-per730-01 ~]# ethtool -K bond0 lro off > [root@dell-per730-01 ~]# ethtool -k bond0 |grep large > large-receive-offload: off > [root@dell-per730-01 ~]# ethtool -k p5p1 |grep large > large-receive-offload: off > > dmesg dump: > > [ 1033.277986] bond0: Disabling feature 0x0000000000008000 on lower dev p5p2. > [ 1034.067949] bnx2x 0000:06:00.1 p5p2: using MSI-X IRQs: sp 74 fp[0] 76 ... fp[7] 83 > [ 1034.753612] bond0: Disabling feature 0x0000000000008000 on lower dev p5p1. > [ 1035.591019] bnx2x 0000:06:00.0 p5p1: using MSI-X IRQs: sp 62 fp[0] 64 ... fp[7] 71 > > This has been successfully tested with bnx2x, qlcnic and netxen network > cards as slaves in a bond interface. Turning LRO on or off on the master > also turns it on or off on each of the slaves, new slaves are added with > LRO in the same state as the master, and LRO can't be toggled on the > slaves. > > Also, this should largely remove the need for dev_disable_lro(), and most, > if not all, of its call sites can be replaced by simply making sure > NETIF_F_LRO isn't included in the relevant device's feature flags. > > Note that this patch is driven by bug reports from users saying it was > confusing that bonds and slaves had different settings for the same > features, and while it won't be 100% in sync if a lower device doesn't > support a feature like LRO, I think this is a good step in the right > direction. > > CC: "David S. Miller" <davem@davemloft.net> > CC: Eric Dumazet <edumazet@google.com> > CC: Jay Vosburgh <j.vosburgh@gmail.com> > CC: Veaceslav Falico <vfalico@gmail.com> > CC: Andy Gospodarek <gospo@cumulusnetworks.com> > CC: Jiri Pirko <jiri@resnulli.us> > CC: Nikolay Aleksandrov <razor@blackwall.org> > CC: Michal Kubecek <mkubecek@suse.cz> > CC: Alexander Duyck <alexander.duyck@gmail.com> > CC: netdev@vger.kernel.org > Signed-off-by: Jarod Wilson <jarod@redhat.com> > --- > Note: this replaces "[RFC PATCH net-next] net/core: initial support for > stacked dev feature toggles" for consideration. > > include/linux/netdev_features.h | 11 +++++++++ > net/core/dev.c | 52 +++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 63 insertions(+) > > diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h > index 9672781..0f5837a 100644 > --- a/include/linux/netdev_features.h > +++ b/include/linux/netdev_features.h > @@ -125,6 +125,11 @@ enum { > #define NETIF_F_HW_L2FW_DOFFLOAD __NETIF_F(HW_L2FW_DOFFLOAD) > #define NETIF_F_BUSY_POLL __NETIF_F(BUSY_POLL) > > +#define for_each_netdev_feature(mask_addr, feature) \ > + int bit; \ > + for_each_set_bit(bit, (unsigned long *)mask_addr, NETDEV_FEATURE_COUNT) \ > + feature = __NETIF_F_BIT(bit); > + > /* Features valid for ethtool to change */ > /* = all defined minus driver/device-class-related */ > #define NETIF_F_NEVER_CHANGE (NETIF_F_VLAN_CHALLENGED | \ > @@ -167,6 +172,12 @@ enum { > */ > #define NETIF_F_ALL_FOR_ALL (NETIF_F_NOCACHE_COPY | NETIF_F_FSO) > > +/* > + * If upper/master device has these features disabled, they must be disabled > + * on all lower/slave devices as well. > + */ > +#define NETIF_F_UPPER_DISABLES NETIF_F_LRO > + > /* changeable features with no special hardware requirements */ > #define NETIF_F_SOFT_FEATURES (NETIF_F_GSO | NETIF_F_GRO) > > diff --git a/net/core/dev.c b/net/core/dev.c > index 13f49f8..3a8dbbc 100644 > --- a/net/core/dev.c > +++ b/net/core/dev.c > @@ -6288,9 +6288,51 @@ static void rollback_registered(struct net_device *dev) > list_del(&single); > } > > +static netdev_features_t netdev_sync_upper_features(struct net_device *lower, > + struct net_device *upper, netdev_features_t features) > +{ > + netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; > + netdev_features_t feature; > + > + for_each_netdev_feature(&upper_disables, feature) { > + if (!(upper->wanted_features & feature) > + && (features & feature)) { > + netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n", > + &feature, upper->name); > + features &= ~feature; > + } > + } > + > + return features; > +} > + > +static void netdev_sync_lower_features(struct net_device *upper, > + struct net_device *lower, netdev_features_t features) > +{ > + netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; > + netdev_features_t feature; > + > + for_each_netdev_feature(&upper_disables, feature) { > + if (!(features & feature) && (lower->features & feature)) { > + netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n", > + &feature, lower->name); > + upper->wanted_features &= ~feature; Isn't this line redundant? The upper device should have already cleared the bit from the wanted_features? That is unless the ndo_fix_features call modified it in which case we shouldn't be modifying it ourselves. > + lower->wanted_features &= ~feature; > + netdev_update_features(lower); > + > + if (unlikely(lower->features & feature)) > + netdev_WARN(upper, "failed to disable %pNF on %s!\n", > + &feature, lower->name); > + } > + } > +} > + > static netdev_features_t netdev_fix_features(struct net_device *dev, > netdev_features_t features) > { > + struct net_device *upper, *lower; > + struct list_head *iter; > + > /* Fix illegal checksum combinations */ > if ((features & NETIF_F_HW_CSUM) && > (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { > @@ -6345,6 +6387,16 @@ static netdev_features_t netdev_fix_features(struct net_device *dev, > } > } > > + /* some features can't be enabled if they're off an an upper device */ > + netdev_for_each_upper_dev_rcu(dev, upper, iter) > + features = netdev_sync_upper_features(dev, upper, features); > + > + /* some features must be disabled on lower devices when disabled > + * on an upper device (think: bonding master or bridge) > + */ > + netdev_for_each_lower_dev(dev, lower, iter) > + netdev_sync_lower_features(dev, lower, features); > + I don't know if this is the right spot for this. You might want to look at placing this after the ndo_set_features call to handle things if there wasn't an error. That way if a lower device for some reason has an issue with one of the other settings being changed you don't end up in a state where all the lower devices have the feature stripped while the upper device still reports it as being enabled. > #ifdef CONFIG_NET_RX_BUSY_POLL > if (dev->netdev_ops->ndo_busy_poll) > features |= NETIF_F_BUSY_POLL; > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Alexander Duyck wrote: > On 11/02/2015 09:53 AM, Jarod Wilson wrote: >> There are some netdev features, which when disabled on an upper device, >> such as a bonding master or a bridge, must be disabled and cannot be >> re-enabled on underlying devices. >> >> This is a rework of an earlier more heavy-handed appraoch, which simply >> disables and prevents re-enabling of netdev features listed in a new >> define in include/net/netdev_features.h, NETIF_F_UPPER_DISABLES. Any >> upper >> device that disables a flag in that feature mask, the disabling will >> propagate down the stack, and any lower device that has any upper device >> with one of those flags disabled should not be able to enable said flag. >> >> Initially, only LRO is included for proof of concept, and because this >> code effectively does the same thing as dev_disable_lro(), though it will >> also activate from the ethtool path, which was one of the goals here. >> >> [root@dell-per730-01 ~]# ethtool -k bond0 |grep large >> large-receive-offload: on >> [root@dell-per730-01 ~]# ethtool -k p5p1 |grep large >> large-receive-offload: on >> [root@dell-per730-01 ~]# ethtool -K bond0 lro off >> [root@dell-per730-01 ~]# ethtool -k bond0 |grep large >> large-receive-offload: off >> [root@dell-per730-01 ~]# ethtool -k p5p1 |grep large >> large-receive-offload: off >> >> dmesg dump: >> >> [ 1033.277986] bond0: Disabling feature 0x0000000000008000 on lower >> dev p5p2. >> [ 1034.067949] bnx2x 0000:06:00.1 p5p2: using MSI-X IRQs: sp 74 fp[0] >> 76 ... fp[7] 83 >> [ 1034.753612] bond0: Disabling feature 0x0000000000008000 on lower >> dev p5p1. >> [ 1035.591019] bnx2x 0000:06:00.0 p5p1: using MSI-X IRQs: sp 62 fp[0] >> 64 ... fp[7] 71 >> >> This has been successfully tested with bnx2x, qlcnic and netxen network >> cards as slaves in a bond interface. Turning LRO on or off on the master >> also turns it on or off on each of the slaves, new slaves are added with >> LRO in the same state as the master, and LRO can't be toggled on the >> slaves. >> >> Also, this should largely remove the need for dev_disable_lro(), and >> most, >> if not all, of its call sites can be replaced by simply making sure >> NETIF_F_LRO isn't included in the relevant device's feature flags. >> >> Note that this patch is driven by bug reports from users saying it was >> confusing that bonds and slaves had different settings for the same >> features, and while it won't be 100% in sync if a lower device doesn't >> support a feature like LRO, I think this is a good step in the right >> direction. >> >> CC: "David S. Miller" <davem@davemloft.net> >> CC: Eric Dumazet <edumazet@google.com> >> CC: Jay Vosburgh <j.vosburgh@gmail.com> >> CC: Veaceslav Falico <vfalico@gmail.com> >> CC: Andy Gospodarek <gospo@cumulusnetworks.com> >> CC: Jiri Pirko <jiri@resnulli.us> >> CC: Nikolay Aleksandrov <razor@blackwall.org> >> CC: Michal Kubecek <mkubecek@suse.cz> >> CC: Alexander Duyck <alexander.duyck@gmail.com> >> CC: netdev@vger.kernel.org >> Signed-off-by: Jarod Wilson <jarod@redhat.com> >> --- >> Note: this replaces "[RFC PATCH net-next] net/core: initial support for >> stacked dev feature toggles" for consideration. >> >> include/linux/netdev_features.h | 11 +++++++++ >> net/core/dev.c | 52 +++++++++++++++++++++++++++++++++++++++++ >> 2 files changed, 63 insertions(+) >> >> diff --git a/include/linux/netdev_features.h >> b/include/linux/netdev_features.h >> index 9672781..0f5837a 100644 >> --- a/include/linux/netdev_features.h >> +++ b/include/linux/netdev_features.h >> @@ -125,6 +125,11 @@ enum { >> #define NETIF_F_HW_L2FW_DOFFLOAD __NETIF_F(HW_L2FW_DOFFLOAD) >> #define NETIF_F_BUSY_POLL __NETIF_F(BUSY_POLL) >> >> +#define for_each_netdev_feature(mask_addr, feature) \ >> + int bit; \ >> + for_each_set_bit(bit, (unsigned long *)mask_addr, >> NETDEV_FEATURE_COUNT) \ >> + feature = __NETIF_F_BIT(bit); >> + >> /* Features valid for ethtool to change */ >> /* = all defined minus driver/device-class-related */ >> #define NETIF_F_NEVER_CHANGE (NETIF_F_VLAN_CHALLENGED | \ >> @@ -167,6 +172,12 @@ enum { >> */ >> #define NETIF_F_ALL_FOR_ALL (NETIF_F_NOCACHE_COPY | NETIF_F_FSO) >> >> +/* >> + * If upper/master device has these features disabled, they must be >> disabled >> + * on all lower/slave devices as well. >> + */ >> +#define NETIF_F_UPPER_DISABLES NETIF_F_LRO >> + >> /* changeable features with no special hardware requirements */ >> #define NETIF_F_SOFT_FEATURES (NETIF_F_GSO | NETIF_F_GRO) >> >> diff --git a/net/core/dev.c b/net/core/dev.c >> index 13f49f8..3a8dbbc 100644 >> --- a/net/core/dev.c >> +++ b/net/core/dev.c >> @@ -6288,9 +6288,51 @@ static void rollback_registered(struct >> net_device *dev) >> list_del(&single); >> } >> >> +static netdev_features_t netdev_sync_upper_features(struct net_device >> *lower, >> + struct net_device *upper, netdev_features_t features) >> +{ >> + netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; >> + netdev_features_t feature; >> + >> + for_each_netdev_feature(&upper_disables, feature) { >> + if (!(upper->wanted_features & feature) >> + && (features & feature)) { >> + netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n", >> + &feature, upper->name); >> + features &= ~feature; >> + } >> + } >> + >> + return features; >> +} >> + >> +static void netdev_sync_lower_features(struct net_device *upper, >> + struct net_device *lower, netdev_features_t features) >> +{ >> + netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; >> + netdev_features_t feature; >> + >> + for_each_netdev_feature(&upper_disables, feature) { >> + if (!(features & feature) && (lower->features & feature)) { >> + netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n", >> + &feature, lower->name); >> + upper->wanted_features &= ~feature; > > Isn't this line redundant? The upper device should have already cleared > the bit from the wanted_features? That is unless the ndo_fix_features > call modified it in which case we shouldn't be modifying it ourselves. With the upper/lower feature sync calls where they currently are, no, its actually necessary to prevent flip-flopping flag values. ... >> @@ -6345,6 +6387,16 @@ static netdev_features_t >> netdev_fix_features(struct net_device *dev, >> } >> } >> >> + /* some features can't be enabled if they're off an an upper device */ >> + netdev_for_each_upper_dev_rcu(dev, upper, iter) >> + features = netdev_sync_upper_features(dev, upper, features); >> + >> + /* some features must be disabled on lower devices when disabled >> + * on an upper device (think: bonding master or bridge) >> + */ >> + netdev_for_each_lower_dev(dev, lower, iter) >> + netdev_sync_lower_features(dev, lower, features); >> + > > I don't know if this is the right spot for this. You might want to look > at placing this after the ndo_set_features call to handle things if > there wasn't an error. That way if a lower device for some reason has an > issue with one of the other settings being changed you don't end up in a > state where all the lower devices have the feature stripped while the > upper device still reports it as being enabled. I'll give it a go after the .ndo_set_features calls in __netdev_update_features(), see what shakes loose. Might even not need the extra upper->wanted_features twiddling with it here.
diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h index 9672781..0f5837a 100644 --- a/include/linux/netdev_features.h +++ b/include/linux/netdev_features.h @@ -125,6 +125,11 @@ enum { #define NETIF_F_HW_L2FW_DOFFLOAD __NETIF_F(HW_L2FW_DOFFLOAD) #define NETIF_F_BUSY_POLL __NETIF_F(BUSY_POLL) +#define for_each_netdev_feature(mask_addr, feature) \ + int bit; \ + for_each_set_bit(bit, (unsigned long *)mask_addr, NETDEV_FEATURE_COUNT) \ + feature = __NETIF_F_BIT(bit); + /* Features valid for ethtool to change */ /* = all defined minus driver/device-class-related */ #define NETIF_F_NEVER_CHANGE (NETIF_F_VLAN_CHALLENGED | \ @@ -167,6 +172,12 @@ enum { */ #define NETIF_F_ALL_FOR_ALL (NETIF_F_NOCACHE_COPY | NETIF_F_FSO) +/* + * If upper/master device has these features disabled, they must be disabled + * on all lower/slave devices as well. + */ +#define NETIF_F_UPPER_DISABLES NETIF_F_LRO + /* changeable features with no special hardware requirements */ #define NETIF_F_SOFT_FEATURES (NETIF_F_GSO | NETIF_F_GRO) diff --git a/net/core/dev.c b/net/core/dev.c index 13f49f8..3a8dbbc 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -6288,9 +6288,51 @@ static void rollback_registered(struct net_device *dev) list_del(&single); } +static netdev_features_t netdev_sync_upper_features(struct net_device *lower, + struct net_device *upper, netdev_features_t features) +{ + netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; + netdev_features_t feature; + + for_each_netdev_feature(&upper_disables, feature) { + if (!(upper->wanted_features & feature) + && (features & feature)) { + netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n", + &feature, upper->name); + features &= ~feature; + } + } + + return features; +} + +static void netdev_sync_lower_features(struct net_device *upper, + struct net_device *lower, netdev_features_t features) +{ + netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; + netdev_features_t feature; + + for_each_netdev_feature(&upper_disables, feature) { + if (!(features & feature) && (lower->features & feature)) { + netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n", + &feature, lower->name); + upper->wanted_features &= ~feature; + lower->wanted_features &= ~feature; + netdev_update_features(lower); + + if (unlikely(lower->features & feature)) + netdev_WARN(upper, "failed to disable %pNF on %s!\n", + &feature, lower->name); + } + } +} + static netdev_features_t netdev_fix_features(struct net_device *dev, netdev_features_t features) { + struct net_device *upper, *lower; + struct list_head *iter; + /* Fix illegal checksum combinations */ if ((features & NETIF_F_HW_CSUM) && (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { @@ -6345,6 +6387,16 @@ static netdev_features_t netdev_fix_features(struct net_device *dev, } } + /* some features can't be enabled if they're off an an upper device */ + netdev_for_each_upper_dev_rcu(dev, upper, iter) + features = netdev_sync_upper_features(dev, upper, features); + + /* some features must be disabled on lower devices when disabled + * on an upper device (think: bonding master or bridge) + */ + netdev_for_each_lower_dev(dev, lower, iter) + netdev_sync_lower_features(dev, lower, features); + #ifdef CONFIG_NET_RX_BUSY_POLL if (dev->netdev_ops->ndo_busy_poll) features |= NETIF_F_BUSY_POLL;
There are some netdev features, which when disabled on an upper device, such as a bonding master or a bridge, must be disabled and cannot be re-enabled on underlying devices. This is a rework of an earlier more heavy-handed appraoch, which simply disables and prevents re-enabling of netdev features listed in a new define in include/net/netdev_features.h, NETIF_F_UPPER_DISABLES. Any upper device that disables a flag in that feature mask, the disabling will propagate down the stack, and any lower device that has any upper device with one of those flags disabled should not be able to enable said flag. Initially, only LRO is included for proof of concept, and because this code effectively does the same thing as dev_disable_lro(), though it will also activate from the ethtool path, which was one of the goals here. [root@dell-per730-01 ~]# ethtool -k bond0 |grep large large-receive-offload: on [root@dell-per730-01 ~]# ethtool -k p5p1 |grep large large-receive-offload: on [root@dell-per730-01 ~]# ethtool -K bond0 lro off [root@dell-per730-01 ~]# ethtool -k bond0 |grep large large-receive-offload: off [root@dell-per730-01 ~]# ethtool -k p5p1 |grep large large-receive-offload: off dmesg dump: [ 1033.277986] bond0: Disabling feature 0x0000000000008000 on lower dev p5p2. [ 1034.067949] bnx2x 0000:06:00.1 p5p2: using MSI-X IRQs: sp 74 fp[0] 76 ... fp[7] 83 [ 1034.753612] bond0: Disabling feature 0x0000000000008000 on lower dev p5p1. [ 1035.591019] bnx2x 0000:06:00.0 p5p1: using MSI-X IRQs: sp 62 fp[0] 64 ... fp[7] 71 This has been successfully tested with bnx2x, qlcnic and netxen network cards as slaves in a bond interface. Turning LRO on or off on the master also turns it on or off on each of the slaves, new slaves are added with LRO in the same state as the master, and LRO can't be toggled on the slaves. Also, this should largely remove the need for dev_disable_lro(), and most, if not all, of its call sites can be replaced by simply making sure NETIF_F_LRO isn't included in the relevant device's feature flags. Note that this patch is driven by bug reports from users saying it was confusing that bonds and slaves had different settings for the same features, and while it won't be 100% in sync if a lower device doesn't support a feature like LRO, I think this is a good step in the right direction. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jay Vosburgh <j.vosburgh@gmail.com> CC: Veaceslav Falico <vfalico@gmail.com> CC: Andy Gospodarek <gospo@cumulusnetworks.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Nikolay Aleksandrov <razor@blackwall.org> CC: Michal Kubecek <mkubecek@suse.cz> CC: Alexander Duyck <alexander.duyck@gmail.com> CC: netdev@vger.kernel.org Signed-off-by: Jarod Wilson <jarod@redhat.com> --- Note: this replaces "[RFC PATCH net-next] net/core: initial support for stacked dev feature toggles" for consideration. include/linux/netdev_features.h | 11 +++++++++ net/core/dev.c | 52 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 63 insertions(+)