diff mbox series

[v2,net-next,1/7] net: dsa: move dsa_port :: stp_state near dsa_port :: mac

Message ID 20220105132141.2648876-2-vladimir.oltean@nxp.com (mailing list archive)
State Accepted
Delegated to: Netdev Maintainers
Headers show
Series Cleanup to main DSA structures | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 18 this patch: 18
netdev/cc_maintainers warning 2 maintainers not CCed: olteanv@gmail.com linux@armlinux.org.uk
netdev/build_clang success Errors and warnings before: 26 this patch: 26
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 20 this patch: 20
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 15 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Vladimir Oltean Jan. 5, 2022, 1:21 p.m. UTC
The MAC address of a port is 6 octets in size, and this creates a 2
octet hole after it. There are some other u8 members of struct dsa_port
that we can put in that hole. One such member is the stp_state.

Before:

pahole -C dsa_port net/dsa/slave.o
struct dsa_port {
        union {
                struct net_device * master;              /*     0     8 */
                struct net_device * slave;               /*     0     8 */
        };                                               /*     0     8 */
        const struct dsa_device_ops  * tag_ops;          /*     8     8 */
        struct dsa_switch_tree *   dst;                  /*    16     8 */
        struct sk_buff *           (*rcv)(struct sk_buff *, struct net_device *); /*    24     8 */
        enum {
                DSA_PORT_TYPE_UNUSED = 0,
                DSA_PORT_TYPE_CPU    = 1,
                DSA_PORT_TYPE_DSA    = 2,
                DSA_PORT_TYPE_USER   = 3,
        } type;                                          /*    32     4 */

        /* XXX 4 bytes hole, try to pack */

        struct dsa_switch *        ds;                   /*    40     8 */
        unsigned int               index;                /*    48     4 */

        /* XXX 4 bytes hole, try to pack */

        const char  *              name;                 /*    56     8 */
        /* --- cacheline 1 boundary (64 bytes) --- */
        struct dsa_port *          cpu_dp;               /*    64     8 */
        u8                         mac[6];               /*    72     6 */

        /* XXX 2 bytes hole, try to pack */

        struct device_node *       dn;                   /*    80     8 */
        unsigned int               ageing_time;          /*    88     4 */
        bool                       vlan_filtering;       /*    92     1 */
        bool                       learning;             /*    93     1 */
        u8                         stp_state;            /*    94     1 */

        /* XXX 1 byte hole, try to pack */

        struct dsa_bridge *        bridge;               /*    96     8 */
        struct devlink_port        devlink_port;         /*   104   288 */
        /* --- cacheline 6 boundary (384 bytes) was 8 bytes ago --- */
        bool                       devlink_port_setup;   /*   392     1 */

        /* XXX 7 bytes hole, try to pack */

        struct phylink *           pl;                   /*   400     8 */
        struct phylink_config      pl_config;            /*   408    40 */
        /* --- cacheline 7 boundary (448 bytes) --- */
        struct net_device *        lag_dev;              /*   448     8 */
        bool                       lag_tx_enabled;       /*   456     1 */

        /* XXX 7 bytes hole, try to pack */

        struct net_device *        hsr_dev;              /*   464     8 */
        struct list_head           list;                 /*   472    16 */
        const struct ethtool_ops  * orig_ethtool_ops;    /*   488     8 */
        const struct dsa_netdevice_ops  * netdev_ops;    /*   496     8 */
        struct mutex               addr_lists_lock;      /*   504    32 */
        /* --- cacheline 8 boundary (512 bytes) was 24 bytes ago --- */
        struct list_head           fdbs;                 /*   536    16 */
        struct list_head           mdbs;                 /*   552    16 */
        bool                       setup;                /*   568     1 */

        /* size: 576, cachelines: 9, members: 30 */
        /* sum members: 544, holes: 6, sum holes: 25 */
        /* padding: 7 */
};

After:

pahole -C dsa_port net/dsa/slave.o
struct dsa_port {
        union {
                struct net_device * master;              /*     0     8 */
                struct net_device * slave;               /*     0     8 */
        };                                               /*     0     8 */
        const struct dsa_device_ops  * tag_ops;          /*     8     8 */
        struct dsa_switch_tree *   dst;                  /*    16     8 */
        struct sk_buff *           (*rcv)(struct sk_buff *, struct net_device *); /*    24     8 */
        enum {
                DSA_PORT_TYPE_UNUSED = 0,
                DSA_PORT_TYPE_CPU    = 1,
                DSA_PORT_TYPE_DSA    = 2,
                DSA_PORT_TYPE_USER   = 3,
        } type;                                          /*    32     4 */

        /* XXX 4 bytes hole, try to pack */

        struct dsa_switch *        ds;                   /*    40     8 */
        unsigned int               index;                /*    48     4 */

        /* XXX 4 bytes hole, try to pack */

        const char  *              name;                 /*    56     8 */
        /* --- cacheline 1 boundary (64 bytes) --- */
        struct dsa_port *          cpu_dp;               /*    64     8 */
        u8                         mac[6];               /*    72     6 */
        u8                         stp_state;            /*    78     1 */

        /* XXX 1 byte hole, try to pack */

        struct device_node *       dn;                   /*    80     8 */
        unsigned int               ageing_time;          /*    88     4 */
        bool                       vlan_filtering;       /*    92     1 */
        bool                       learning;             /*    93     1 */

        /* XXX 2 bytes hole, try to pack */

        struct dsa_bridge *        bridge;               /*    96     8 */
        struct devlink_port        devlink_port;         /*   104   288 */
        /* --- cacheline 6 boundary (384 bytes) was 8 bytes ago --- */
        bool                       devlink_port_setup;   /*   392     1 */

        /* XXX 7 bytes hole, try to pack */

        struct phylink *           pl;                   /*   400     8 */
        struct phylink_config      pl_config;            /*   408    40 */
        /* --- cacheline 7 boundary (448 bytes) --- */
        struct net_device *        lag_dev;              /*   448     8 */
        bool                       lag_tx_enabled;       /*   456     1 */

        /* XXX 7 bytes hole, try to pack */

        struct net_device *        hsr_dev;              /*   464     8 */
        struct list_head           list;                 /*   472    16 */
        const struct ethtool_ops  * orig_ethtool_ops;    /*   488     8 */
        const struct dsa_netdevice_ops  * netdev_ops;    /*   496     8 */
        struct mutex               addr_lists_lock;      /*   504    32 */
        /* --- cacheline 8 boundary (512 bytes) was 24 bytes ago --- */
        struct list_head           fdbs;                 /*   536    16 */
        struct list_head           mdbs;                 /*   552    16 */
        bool                       setup;                /*   568     1 */

        /* size: 576, cachelines: 9, members: 30 */
        /* sum members: 544, holes: 6, sum holes: 25 */
        /* padding: 7 */
};

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
 include/net/dsa.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Comments

Florian Fainelli Jan. 5, 2022, 6:30 p.m. UTC | #1
On 1/5/22 5:21 AM, Vladimir Oltean wrote:
> The MAC address of a port is 6 octets in size, and this creates a 2
> octet hole after it. There are some other u8 members of struct dsa_port
> that we can put in that hole. One such member is the stp_state.
> 
> Before:
> 
> pahole -C dsa_port net/dsa/slave.o
> struct dsa_port {
>         union {
>                 struct net_device * master;              /*     0     8 */
>                 struct net_device * slave;               /*     0     8 */
>         };                                               /*     0     8 */
>         const struct dsa_device_ops  * tag_ops;          /*     8     8 */
>         struct dsa_switch_tree *   dst;                  /*    16     8 */
>         struct sk_buff *           (*rcv)(struct sk_buff *, struct net_device *); /*    24     8 */
>         enum {
>                 DSA_PORT_TYPE_UNUSED = 0,
>                 DSA_PORT_TYPE_CPU    = 1,
>                 DSA_PORT_TYPE_DSA    = 2,
>                 DSA_PORT_TYPE_USER   = 3,
>         } type;                                          /*    32     4 */
> 
>         /* XXX 4 bytes hole, try to pack */
> 
>         struct dsa_switch *        ds;                   /*    40     8 */
>         unsigned int               index;                /*    48     4 */
> 
>         /* XXX 4 bytes hole, try to pack */
> 
>         const char  *              name;                 /*    56     8 */
>         /* --- cacheline 1 boundary (64 bytes) --- */
>         struct dsa_port *          cpu_dp;               /*    64     8 */
>         u8                         mac[6];               /*    72     6 */
> 
>         /* XXX 2 bytes hole, try to pack */
> 
>         struct device_node *       dn;                   /*    80     8 */
>         unsigned int               ageing_time;          /*    88     4 */
>         bool                       vlan_filtering;       /*    92     1 */
>         bool                       learning;             /*    93     1 */
>         u8                         stp_state;            /*    94     1 */
> 
>         /* XXX 1 byte hole, try to pack */
> 
>         struct dsa_bridge *        bridge;               /*    96     8 */
>         struct devlink_port        devlink_port;         /*   104   288 */
>         /* --- cacheline 6 boundary (384 bytes) was 8 bytes ago --- */
>         bool                       devlink_port_setup;   /*   392     1 */
> 
>         /* XXX 7 bytes hole, try to pack */
> 
>         struct phylink *           pl;                   /*   400     8 */
>         struct phylink_config      pl_config;            /*   408    40 */
>         /* --- cacheline 7 boundary (448 bytes) --- */
>         struct net_device *        lag_dev;              /*   448     8 */
>         bool                       lag_tx_enabled;       /*   456     1 */
> 
>         /* XXX 7 bytes hole, try to pack */
> 
>         struct net_device *        hsr_dev;              /*   464     8 */
>         struct list_head           list;                 /*   472    16 */
>         const struct ethtool_ops  * orig_ethtool_ops;    /*   488     8 */
>         const struct dsa_netdevice_ops  * netdev_ops;    /*   496     8 */
>         struct mutex               addr_lists_lock;      /*   504    32 */
>         /* --- cacheline 8 boundary (512 bytes) was 24 bytes ago --- */
>         struct list_head           fdbs;                 /*   536    16 */
>         struct list_head           mdbs;                 /*   552    16 */
>         bool                       setup;                /*   568     1 */
> 
>         /* size: 576, cachelines: 9, members: 30 */
>         /* sum members: 544, holes: 6, sum holes: 25 */
>         /* padding: 7 */
> };
> 
> After:
> 
> pahole -C dsa_port net/dsa/slave.o
> struct dsa_port {
>         union {
>                 struct net_device * master;              /*     0     8 */
>                 struct net_device * slave;               /*     0     8 */
>         };                                               /*     0     8 */
>         const struct dsa_device_ops  * tag_ops;          /*     8     8 */
>         struct dsa_switch_tree *   dst;                  /*    16     8 */
>         struct sk_buff *           (*rcv)(struct sk_buff *, struct net_device *); /*    24     8 */
>         enum {
>                 DSA_PORT_TYPE_UNUSED = 0,
>                 DSA_PORT_TYPE_CPU    = 1,
>                 DSA_PORT_TYPE_DSA    = 2,
>                 DSA_PORT_TYPE_USER   = 3,
>         } type;                                          /*    32     4 */
> 
>         /* XXX 4 bytes hole, try to pack */
> 
>         struct dsa_switch *        ds;                   /*    40     8 */
>         unsigned int               index;                /*    48     4 */
> 
>         /* XXX 4 bytes hole, try to pack */
> 
>         const char  *              name;                 /*    56     8 */
>         /* --- cacheline 1 boundary (64 bytes) --- */
>         struct dsa_port *          cpu_dp;               /*    64     8 */
>         u8                         mac[6];               /*    72     6 */
>         u8                         stp_state;            /*    78     1 */
> 
>         /* XXX 1 byte hole, try to pack */
> 
>         struct device_node *       dn;                   /*    80     8 */
>         unsigned int               ageing_time;          /*    88     4 */
>         bool                       vlan_filtering;       /*    92     1 */
>         bool                       learning;             /*    93     1 */
> 
>         /* XXX 2 bytes hole, try to pack */
> 
>         struct dsa_bridge *        bridge;               /*    96     8 */
>         struct devlink_port        devlink_port;         /*   104   288 */
>         /* --- cacheline 6 boundary (384 bytes) was 8 bytes ago --- */
>         bool                       devlink_port_setup;   /*   392     1 */
> 
>         /* XXX 7 bytes hole, try to pack */
> 
>         struct phylink *           pl;                   /*   400     8 */
>         struct phylink_config      pl_config;            /*   408    40 */
>         /* --- cacheline 7 boundary (448 bytes) --- */
>         struct net_device *        lag_dev;              /*   448     8 */
>         bool                       lag_tx_enabled;       /*   456     1 */
> 
>         /* XXX 7 bytes hole, try to pack */
> 
>         struct net_device *        hsr_dev;              /*   464     8 */
>         struct list_head           list;                 /*   472    16 */
>         const struct ethtool_ops  * orig_ethtool_ops;    /*   488     8 */
>         const struct dsa_netdevice_ops  * netdev_ops;    /*   496     8 */
>         struct mutex               addr_lists_lock;      /*   504    32 */
>         /* --- cacheline 8 boundary (512 bytes) was 24 bytes ago --- */
>         struct list_head           fdbs;                 /*   536    16 */
>         struct list_head           mdbs;                 /*   552    16 */
>         bool                       setup;                /*   568     1 */
> 
>         /* size: 576, cachelines: 9, members: 30 */
>         /* sum members: 544, holes: 6, sum holes: 25 */
>         /* padding: 7 */
> };
> 
> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
diff mbox series

Patch

diff --git a/include/net/dsa.h b/include/net/dsa.h
index f16959444ae1..8878f9ce251b 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -258,12 +258,14 @@  struct dsa_port {
 	const char		*name;
 	struct dsa_port		*cpu_dp;
 	u8			mac[ETH_ALEN];
+
+	u8			stp_state;
+
 	struct device_node	*dn;
 	unsigned int		ageing_time;
 	bool			vlan_filtering;
 	/* Managed by DSA on user ports and by drivers on CPU and DSA ports */
 	bool			learning;
-	u8			stp_state;
 	struct dsa_bridge	*bridge;
 	struct devlink_port	devlink_port;
 	bool			devlink_port_setup;