| Message ID | 20220105132141.2648876-8-vladimir.oltean@nxp.com (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | Cleanup to main DSA structures | expand |
On 1/5/22 5:21 AM, Vladimir Oltean wrote: > There is a 7 byte hole after dst->setup and a 4 byte hole after > dst->default_proto. Combining them, we have a single hole of just 3 > bytes on 64 bit machines. > > Before: > > pahole -C dsa_switch_tree net/dsa/slave.o > struct dsa_switch_tree { > struct list_head list; /* 0 16 */ > struct list_head ports; /* 16 16 */ > struct raw_notifier_head nh; /* 32 8 */ > unsigned int index; /* 40 4 */ > struct kref refcount; /* 44 4 */ > struct net_device * * lags; /* 48 8 */ > bool setup; /* 56 1 */ > > /* XXX 7 bytes hole, try to pack */ > > /* --- cacheline 1 boundary (64 bytes) --- */ > const struct dsa_device_ops * tag_ops; /* 64 8 */ > enum dsa_tag_protocol default_proto; /* 72 4 */ > > /* XXX 4 bytes hole, try to pack */ > > struct dsa_platform_data * pd; /* 80 8 */ > struct list_head rtable; /* 88 16 */ > unsigned int lags_len; /* 104 4 */ > unsigned int last_switch; /* 108 4 */ > > /* size: 112, cachelines: 2, members: 13 */ > /* sum members: 101, holes: 2, sum holes: 11 */ > /* last cacheline: 48 bytes */ > }; > > After: > > pahole -C dsa_switch_tree net/dsa/slave.o > struct dsa_switch_tree { > struct list_head list; /* 0 16 */ > struct list_head ports; /* 16 16 */ > struct raw_notifier_head nh; /* 32 8 */ > unsigned int index; /* 40 4 */ > struct kref refcount; /* 44 4 */ > struct net_device * * lags; /* 48 8 */ > const struct dsa_device_ops * tag_ops; /* 56 8 */ > /* --- cacheline 1 boundary (64 bytes) --- */ > enum dsa_tag_protocol default_proto; /* 64 4 */ > bool setup; /* 68 1 */ > > /* XXX 3 bytes hole, try to pack */ > > struct dsa_platform_data * pd; /* 72 8 */ > struct list_head rtable; /* 80 16 */ > unsigned int lags_len; /* 96 4 */ > unsigned int last_switch; /* 100 4 */ > > /* size: 104, cachelines: 2, members: 13 */ > /* sum members: 101, holes: 1, sum holes: 3 */ > /* last cacheline: 40 bytes */ > }; > > Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
diff --git a/include/net/dsa.h b/include/net/dsa.h index cbbac75138d9..5d0fec6db3ae 100644 --- a/include/net/dsa.h +++ b/include/net/dsa.h @@ -136,9 +136,6 @@ struct dsa_switch_tree { */ struct net_device **lags; - /* Has this tree been applied to the hardware? */ - bool setup; - /* Tagging protocol operations */ const struct dsa_device_ops *tag_ops; @@ -147,6 +144,9 @@ struct dsa_switch_tree { */ enum dsa_tag_protocol default_proto; + /* Has this tree been applied to the hardware? */ + bool setup; + /* * Configuration data for the platform device that owns * this dsa switch tree instance.
There is a 7 byte hole after dst->setup and a 4 byte hole after dst->default_proto. Combining them, we have a single hole of just 3 bytes on 64 bit machines. Before: pahole -C dsa_switch_tree net/dsa/slave.o struct dsa_switch_tree { struct list_head list; /* 0 16 */ struct list_head ports; /* 16 16 */ struct raw_notifier_head nh; /* 32 8 */ unsigned int index; /* 40 4 */ struct kref refcount; /* 44 4 */ struct net_device * * lags; /* 48 8 */ bool setup; /* 56 1 */ /* XXX 7 bytes hole, try to pack */ /* --- cacheline 1 boundary (64 bytes) --- */ const struct dsa_device_ops * tag_ops; /* 64 8 */ enum dsa_tag_protocol default_proto; /* 72 4 */ /* XXX 4 bytes hole, try to pack */ struct dsa_platform_data * pd; /* 80 8 */ struct list_head rtable; /* 88 16 */ unsigned int lags_len; /* 104 4 */ unsigned int last_switch; /* 108 4 */ /* size: 112, cachelines: 2, members: 13 */ /* sum members: 101, holes: 2, sum holes: 11 */ /* last cacheline: 48 bytes */ }; After: pahole -C dsa_switch_tree net/dsa/slave.o struct dsa_switch_tree { struct list_head list; /* 0 16 */ struct list_head ports; /* 16 16 */ struct raw_notifier_head nh; /* 32 8 */ unsigned int index; /* 40 4 */ struct kref refcount; /* 44 4 */ struct net_device * * lags; /* 48 8 */ const struct dsa_device_ops * tag_ops; /* 56 8 */ /* --- cacheline 1 boundary (64 bytes) --- */ enum dsa_tag_protocol default_proto; /* 64 4 */ bool setup; /* 68 1 */ /* XXX 3 bytes hole, try to pack */ struct dsa_platform_data * pd; /* 72 8 */ struct list_head rtable; /* 80 16 */ unsigned int lags_len; /* 96 4 */ unsigned int last_switch; /* 100 4 */ /* size: 104, cachelines: 2, members: 13 */ /* sum members: 101, holes: 1, sum holes: 3 */ /* last cacheline: 40 bytes */ }; Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> --- include/net/dsa.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)