From c69de58ba84f480879de64571d9dae5102d10ed6 Mon Sep 17 00:00:00 2001 From: William Tu Date: Thu, 25 Jan 2018 13:20:09 -0800 Subject: net: erspan: use bitfield instead of mask and offset Originally the erspan fields are defined as a group into a __be16 field, and use mask and offset to access each field. This is more costly due to calling ntohs/htons. The patch changes it to use bitfields. Signed-off-by: William Tu Acked-by: Pravin B Shelar Signed-off-by: David S. Miller --- include/net/erspan.h | 127 ++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 94 insertions(+), 33 deletions(-) (limited to 'include/net') diff --git a/include/net/erspan.h b/include/net/erspan.h index 712ea1b1f4db..6d30fe898286 100644 --- a/include/net/erspan.h +++ b/include/net/erspan.h @@ -65,16 +65,30 @@ #define GRA_MASK 0x0006 #define O_MASK 0x0001 +#define HWID_OFFSET 4 +#define DIR_OFFSET 3 + /* ERSPAN version 2 metadata header */ struct erspan_md2 { __be32 timestamp; __be16 sgt; /* security group tag */ - __be16 flags; -#define P_OFFSET 15 -#define FT_OFFSET 10 -#define HWID_OFFSET 4 -#define DIR_OFFSET 3 -#define GRA_OFFSET 1 +#if defined(__LITTLE_ENDIAN_BITFIELD) + __u8 hwid_upper:2, + ft:5, + p:1; + __u8 o:1, + gra:2, + dir:1, + hwid:4; +#elif defined(__BIG_ENDIAN_BITFIELD) + __u8 p:1, + ft:5, + hwid_upper:2; + __u8 hwid:4, + dir:1, + gra:2, + o:1; +#endif }; enum erspan_encap_type { @@ -95,15 +109,62 @@ struct erspan_metadata { }; struct erspan_base_hdr { - __be16 ver_vlan; -#define VER_OFFSET 12 - __be16 session_id; -#define COS_OFFSET 13 -#define EN_OFFSET 11 -#define BSO_OFFSET EN_OFFSET -#define T_OFFSET 10 +#if defined(__LITTLE_ENDIAN_BITFIELD) + __u8 vlan_upper:4, + ver:4; + __u8 vlan:8; + __u8 session_id_upper:2, + t:1, + en:2, + cos:3; + __u8 session_id:8; +#elif defined(__BIG_ENDIAN_BITFIELD) + __u8 ver: 4, + vlan_upper:4; + __u8 vlan:8; + __u8 cos:3, + en:2, + t:1, + session_id_upper:2; + __u8 session_id:8; +#else +#error "Please fix " +#endif }; +static inline void set_session_id(struct erspan_base_hdr *ershdr, u16 id) +{ + ershdr->session_id = id & 0xff; + ershdr->session_id_upper = (id >> 8) & 0x3; +} + +static inline u16 get_session_id(const struct erspan_base_hdr *ershdr) +{ + return (ershdr->session_id_upper << 8) + ershdr->session_id; +} + +static inline void set_vlan(struct erspan_base_hdr *ershdr, u16 vlan) +{ + ershdr->vlan = vlan & 0xff; + ershdr->vlan_upper = (vlan >> 8) & 0xf; +} + +static inline u16 get_vlan(const struct erspan_base_hdr *ershdr) +{ + return (ershdr->vlan_upper << 8) + ershdr->vlan; +} + +static inline void set_hwid(struct erspan_md2 *md2, u8 hwid) +{ + md2->hwid = hwid & 0xf; + md2->hwid_upper = (hwid >> 4) & 0x3; +} + +static inline u8 get_hwid(const struct erspan_md2 *md2) +{ + return (md2->hwid_upper << 4) + md2->hwid; +} + static inline int erspan_hdr_len(int version) { return sizeof(struct erspan_base_hdr) + @@ -120,7 +181,7 @@ static inline u8 tos_to_cos(u8 tos) } static inline void erspan_build_header(struct sk_buff *skb, - __be32 id, u32 index, + u32 id, u32 index, bool truncate, bool is_ipv4) { struct ethhdr *eth = (struct ethhdr *)skb->data; @@ -154,12 +215,12 @@ static inline void erspan_build_header(struct sk_buff *skb, memset(ershdr, 0, sizeof(*ershdr) + ERSPAN_V1_MDSIZE); /* Build base header */ - ershdr->ver_vlan = htons((vlan_tci & VLAN_MASK) | - (ERSPAN_VERSION << VER_OFFSET)); - ershdr->session_id = htons((u16)(ntohl(id) & ID_MASK) | - ((tos_to_cos(tos) << COS_OFFSET) & COS_MASK) | - (enc_type << EN_OFFSET & EN_MASK) | - ((truncate << T_OFFSET) & T_MASK)); + ershdr->ver = ERSPAN_VERSION; + ershdr->cos = tos_to_cos(tos); + ershdr->en = enc_type; + ershdr->t = truncate; + set_vlan(ershdr, vlan_tci); + set_session_id(ershdr, id); /* Build metadata */ ersmd = (struct erspan_metadata *)(ershdr + 1); @@ -187,7 +248,7 @@ static inline __be32 erspan_get_timestamp(void) } static inline void erspan_build_header_v2(struct sk_buff *skb, - __be32 id, u8 direction, u16 hwid, + u32 id, u8 direction, u16 hwid, bool truncate, bool is_ipv4) { struct ethhdr *eth = (struct ethhdr *)skb->data; @@ -198,7 +259,6 @@ static inline void erspan_build_header_v2(struct sk_buff *skb, __be16 tci; } *qp; u16 vlan_tci = 0; - u16 session_id; u8 gra = 0; /* 100 usec */ u8 bso = 0; /* Bad/Short/Oversized */ u8 sgt = 0; @@ -221,22 +281,23 @@ static inline void erspan_build_header_v2(struct sk_buff *skb, memset(ershdr, 0, sizeof(*ershdr) + ERSPAN_V2_MDSIZE); /* Build base header */ - ershdr->ver_vlan = htons((vlan_tci & VLAN_MASK) | - (ERSPAN_VERSION2 << VER_OFFSET)); - session_id = (u16)(ntohl(id) & ID_MASK) | - ((tos_to_cos(tos) << COS_OFFSET) & COS_MASK) | - (bso << BSO_OFFSET & BSO_MASK) | - ((truncate << T_OFFSET) & T_MASK); - ershdr->session_id = htons(session_id); + ershdr->ver = ERSPAN_VERSION2; + ershdr->cos = tos_to_cos(tos); + ershdr->en = bso; + ershdr->t = truncate; + set_vlan(ershdr, vlan_tci); + set_session_id(ershdr, id); /* Build metadata */ md = (struct erspan_metadata *)(ershdr + 1); md->u.md2.timestamp = erspan_get_timestamp(); md->u.md2.sgt = htons(sgt); - md->u.md2.flags = htons(((1 << P_OFFSET) & P_MASK) | - ((hwid << HWID_OFFSET) & HWID_MASK) | - ((direction << DIR_OFFSET) & DIR_MASK) | - ((gra << GRA_OFFSET) & GRA_MASK)); + md->u.md2.p = 1; + md->u.md2.ft = 0; + md->u.md2.dir = direction; + md->u.md2.gra = gra; + md->u.md2.o = 0; + set_hwid(&md->u.md2, hwid); } #endif -- cgit v1.2.3