From 354259fa73e2aac92ae5e19522adb69a92c15b49 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 9 Nov 2022 09:57:58 +0000 Subject: [PATCH] net: remove skb->vlan_present skb->vlan_present seems redundant. We can instead derive it from this boolean expression: vlan_present = skb->vlan_proto != 0 || skb->vlan_tci != 0 Add a new union, to access both fields in a single load/store when possible. union { u32 vlan_all; struct { __be16 vlan_proto; __u16 vlan_tci; }; }; This allows following patch to remove a conditional test in GRO stack. Note: We move remcsum_offload to keep TC_AT_INGRESS_MASK and SKB_MONO_DELIVERY_TIME_MASK unchanged. Signed-off-by: Eric Dumazet Acked-by: Yonghong Song Acked-by: Martin KaFai Lau Signed-off-by: Jakub Kicinski --- arch/sparc/net/bpf_jit_comp_32.c | 10 ++++----- .../ethernet/marvell/octeontx2/nic/otx2_pf.c | 2 +- include/linux/if_vlan.h | 9 +++----- include/linux/skbuff.h | 18 ++++++++------- lib/test_bpf.c | 1 - net/core/filter.c | 22 +++++++++---------- 6 files changed, 29 insertions(+), 33 deletions(-) diff --git a/arch/sparc/net/bpf_jit_comp_32.c b/arch/sparc/net/bpf_jit_comp_32.c index b1dbf2fa8c0a..a74e5004c6c8 100644 --- a/arch/sparc/net/bpf_jit_comp_32.c +++ b/arch/sparc/net/bpf_jit_comp_32.c @@ -555,11 +555,11 @@ void bpf_jit_compile(struct bpf_prog *fp) emit_skb_load16(vlan_tci, r_A); break; case BPF_ANC | SKF_AD_VLAN_TAG_PRESENT: - __emit_skb_load8(__pkt_vlan_present_offset, r_A); - if (PKT_VLAN_PRESENT_BIT) - emit_alu_K(SRL, PKT_VLAN_PRESENT_BIT); - if (PKT_VLAN_PRESENT_BIT < 7) - emit_andi(r_A, 1, r_A); + emit_skb_load32(vlan_all, r_A); + emit_cmpi(r_A, 0); + emit_branch_off(BE, 12); + emit_nop(); + emit_loadimm(1, r_A); break; case BPF_LD | BPF_W | BPF_LEN: emit_skb_load32(len, r_A); diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c index 303930499a4c..c1ea60bc2630 100644 --- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c +++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c @@ -1973,7 +1973,7 @@ static u16 otx2_select_queue(struct net_device *netdev, struct sk_buff *skb, #endif #ifdef CONFIG_DCB - if (!skb->vlan_present) + if (!skb_vlan_tag_present(skb)) goto pick_tx; vlan_prio = skb->vlan_tci >> 13; diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h index e00c4ee81ff7..6864b89ef868 100644 --- a/include/linux/if_vlan.h +++ b/include/linux/if_vlan.h @@ -76,7 +76,7 @@ static inline bool is_vlan_dev(const struct net_device *dev) return dev->priv_flags & IFF_802_1Q_VLAN; } -#define skb_vlan_tag_present(__skb) ((__skb)->vlan_present) +#define skb_vlan_tag_present(__skb) (!!(__skb)->vlan_all) #define skb_vlan_tag_get(__skb) ((__skb)->vlan_tci) #define skb_vlan_tag_get_id(__skb) ((__skb)->vlan_tci & VLAN_VID_MASK) #define skb_vlan_tag_get_cfi(__skb) (!!((__skb)->vlan_tci & VLAN_CFI_MASK)) @@ -471,7 +471,7 @@ static inline struct sk_buff *vlan_insert_tag_set_proto(struct sk_buff *skb, */ static inline void __vlan_hwaccel_clear_tag(struct sk_buff *skb) { - skb->vlan_present = 0; + skb->vlan_all = 0; } /** @@ -483,9 +483,7 @@ static inline void __vlan_hwaccel_clear_tag(struct sk_buff *skb) */ static inline void __vlan_hwaccel_copy_tag(struct sk_buff *dst, const struct sk_buff *src) { - dst->vlan_present = src->vlan_present; - dst->vlan_proto = src->vlan_proto; - dst->vlan_tci = src->vlan_tci; + dst->vlan_all = src->vlan_all; } /* @@ -519,7 +517,6 @@ static inline void __vlan_hwaccel_put_tag(struct sk_buff *skb, { skb->vlan_proto = vlan_proto; skb->vlan_tci = vlan_tci; - skb->vlan_present = 1; } /** diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 59c9fd55699d..4e464a27adaf 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -818,7 +818,7 @@ typedef unsigned char *sk_buff_data_t; * @mark: Generic packet mark * @reserved_tailroom: (aka @mark) number of bytes of free space available * at the tail of an sk_buff - * @vlan_present: VLAN tag is present + * @vlan_all: vlan fields (proto & tci) * @vlan_proto: vlan encapsulation protocol * @vlan_tci: vlan tag control information * @inner_protocol: Protocol (encapsulation) @@ -951,7 +951,7 @@ struct sk_buff { /* private: */ __u8 __pkt_vlan_present_offset[0]; /* public: */ - __u8 vlan_present:1; /* See PKT_VLAN_PRESENT_BIT */ + __u8 remcsum_offload:1; __u8 csum_complete_sw:1; __u8 csum_level:2; __u8 dst_pending_confirm:1; @@ -966,7 +966,6 @@ struct sk_buff { __u8 ipvs_property:1; __u8 inner_protocol_type:1; - __u8 remcsum_offload:1; #ifdef CONFIG_NET_SWITCHDEV __u8 offload_fwd_mark:1; __u8 offload_l3_fwd_mark:1; @@ -999,8 +998,13 @@ struct sk_buff { __u32 priority; int skb_iif; __u32 hash; - __be16 vlan_proto; - __u16 vlan_tci; + union { + u32 vlan_all; + struct { + __be16 vlan_proto; + __u16 vlan_tci; + }; + }; #if defined(CONFIG_NET_RX_BUSY_POLL) || defined(CONFIG_XPS) union { unsigned int napi_id; @@ -1059,15 +1063,13 @@ struct sk_buff { #endif #define PKT_TYPE_OFFSET offsetof(struct sk_buff, __pkt_type_offset) -/* if you move pkt_vlan_present, tc_at_ingress, or mono_delivery_time +/* if you move tc_at_ingress or mono_delivery_time * around, you also must adapt these constants. */ #ifdef __BIG_ENDIAN_BITFIELD -#define PKT_VLAN_PRESENT_BIT 7 #define TC_AT_INGRESS_MASK (1 << 0) #define SKB_MONO_DELIVERY_TIME_MASK (1 << 2) #else -#define PKT_VLAN_PRESENT_BIT 0 #define TC_AT_INGRESS_MASK (1 << 7) #define SKB_MONO_DELIVERY_TIME_MASK (1 << 5) #endif diff --git a/lib/test_bpf.c b/lib/test_bpf.c index 5820704165a6..ade9ac672adb 100644 --- a/lib/test_bpf.c +++ b/lib/test_bpf.c @@ -14346,7 +14346,6 @@ static struct sk_buff *populate_skb(char *buf, int size) skb->hash = SKB_HASH; skb->queue_mapping = SKB_QUEUE_MAP; skb->vlan_tci = SKB_VLAN_TCI; - skb->vlan_present = SKB_VLAN_PRESENT; skb->vlan_proto = htons(ETH_P_IP); dev_net_set(&dev, &init_net); skb->dev = &dev; diff --git a/net/core/filter.c b/net/core/filter.c index bb0136e7a8e4..358d5e70671a 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -325,11 +325,11 @@ static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg, offsetof(struct sk_buff, vlan_tci)); break; case SKF_AD_VLAN_TAG_PRESENT: - *insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_VLAN_PRESENT_OFFSET); - if (PKT_VLAN_PRESENT_BIT) - *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, PKT_VLAN_PRESENT_BIT); - if (PKT_VLAN_PRESENT_BIT < 7) - *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1); + BUILD_BUG_ON(sizeof_field(struct sk_buff, vlan_all) != 4); + *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg, + offsetof(struct sk_buff, vlan_all)); + *insn++ = BPF_JMP_IMM(BPF_JEQ, dst_reg, 0, 1); + *insn++ = BPF_ALU32_IMM(BPF_MOV, dst_reg, 1); break; } @@ -9290,13 +9290,11 @@ static u32 bpf_convert_ctx_access(enum bpf_access_type type, break; case offsetof(struct __sk_buff, vlan_present): - *target_size = 1; - *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg, - PKT_VLAN_PRESENT_OFFSET); - if (PKT_VLAN_PRESENT_BIT) - *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, PKT_VLAN_PRESENT_BIT); - if (PKT_VLAN_PRESENT_BIT < 7) - *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1); + *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, + bpf_target_off(struct sk_buff, + vlan_all, 4, target_size)); + *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1); + *insn++ = BPF_ALU32_IMM(BPF_MOV, si->dst_reg, 1); break; case offsetof(struct __sk_buff, vlan_tci):