net: Add additional bit to support clockid_t timestamp type

tstamp_type is now set based on actual clockid_t compressed
into 2 bits.

To make the design scalable for future needs this commit bring in
the change to extend the tstamp_type:1 to tstamp_type:2 to support
other clockid_t timestamp.

We now support CLOCK_TAI as part of tstamp_type as part of this
commit with existing support CLOCK_MONOTONIC and CLOCK_REALTIME.

Signed-off-by: Abhishek Chauhan <quic_abchauha@quicinc.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240509211834.3235191-3-quic_abchauha@quicinc.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
This commit is contained in:
Abhishek Chauhan 2024-05-09 14:18:33 -07:00 committed by Martin KaFai Lau
parent 4d25ca2d68
commit 1693c5db6a
11 changed files with 81 additions and 46 deletions

View File

@ -709,6 +709,8 @@ typedef unsigned char *sk_buff_data_t;
enum skb_tstamp_type {
SKB_CLOCK_REALTIME,
SKB_CLOCK_MONOTONIC,
SKB_CLOCK_TAI,
__SKB_CLOCK_MAX = SKB_CLOCK_TAI,
};
/**
@ -957,7 +959,7 @@ struct sk_buff {
/* private: */
__u8 __mono_tc_offset[0];
/* public: */
__u8 tstamp_type:1; /* See skb_tstamp_type */
__u8 tstamp_type:2; /* See skb_tstamp_type */
#ifdef CONFIG_NET_XGRESS
__u8 tc_at_ingress:1; /* See TC_AT_INGRESS_MASK */
__u8 tc_skip_classify:1;
@ -1087,15 +1089,16 @@ struct sk_buff {
#endif
#define PKT_TYPE_OFFSET offsetof(struct sk_buff, __pkt_type_offset)
/* if you move tc_at_ingress or mono_delivery_time
/* if you move tc_at_ingress or tstamp_type
* around, you also must adapt these constants.
*/
#ifdef __BIG_ENDIAN_BITFIELD
#define SKB_MONO_DELIVERY_TIME_MASK (1 << 7)
#define TC_AT_INGRESS_MASK (1 << 6)
#define SKB_TSTAMP_TYPE_MASK (3 << 6)
#define SKB_TSTAMP_TYPE_RSHIFT (6)
#define TC_AT_INGRESS_MASK (1 << 5)
#else
#define SKB_MONO_DELIVERY_TIME_MASK (1 << 0)
#define TC_AT_INGRESS_MASK (1 << 1)
#define SKB_TSTAMP_TYPE_MASK (3)
#define TC_AT_INGRESS_MASK (1 << 2)
#endif
#define SKB_BF_MONO_TC_OFFSET offsetof(struct sk_buff, __mono_tc_offset)
@ -4216,6 +4219,9 @@ static inline void skb_set_delivery_type_by_clockid(struct sk_buff *skb,
case CLOCK_MONOTONIC:
tstamp_type = SKB_CLOCK_MONOTONIC;
break;
case CLOCK_TAI:
tstamp_type = SKB_CLOCK_TAI;
break;
default:
WARN_ON_ONCE(1);
kt = 0;

View File

@ -6207,12 +6207,17 @@ union { \
__u64 :64; \
} __attribute__((aligned(8)))
/* The enum used in skb->tstamp_type. It specifies the clock type
* of the time stored in the skb->tstamp.
*/
enum {
BPF_SKB_TSTAMP_UNSPEC,
BPF_SKB_TSTAMP_DELIVERY_MONO, /* tstamp has mono delivery time */
/* For any BPF_SKB_TSTAMP_* that the bpf prog cannot handle,
* the bpf prog should handle it like BPF_SKB_TSTAMP_UNSPEC
* and try to deduce it by ingress, egress or skb->sk->sk_clockid.
BPF_SKB_TSTAMP_UNSPEC = 0, /* DEPRECATED */
BPF_SKB_TSTAMP_DELIVERY_MONO = 1, /* DEPRECATED */
BPF_SKB_CLOCK_REALTIME = 0,
BPF_SKB_CLOCK_MONOTONIC = 1,
BPF_SKB_CLOCK_TAI = 2,
/* For any future BPF_SKB_CLOCK_* that the bpf prog cannot handle,
* the bpf prog can try to deduce it by ingress/egress/skb->sk->sk_clockid.
*/
};

View File

@ -7726,17 +7726,21 @@ BPF_CALL_3(bpf_skb_set_tstamp, struct sk_buff *, skb,
return -EOPNOTSUPP;
switch (tstamp_type) {
case BPF_SKB_TSTAMP_DELIVERY_MONO:
case BPF_SKB_CLOCK_REALTIME:
skb->tstamp = tstamp;
skb->tstamp_type = SKB_CLOCK_REALTIME;
break;
case BPF_SKB_CLOCK_MONOTONIC:
if (!tstamp)
return -EINVAL;
skb->tstamp = tstamp;
skb->tstamp_type = SKB_CLOCK_MONOTONIC;
break;
case BPF_SKB_TSTAMP_UNSPEC:
if (tstamp)
case BPF_SKB_CLOCK_TAI:
if (!tstamp)
return -EINVAL;
skb->tstamp = 0;
skb->tstamp_type = SKB_CLOCK_REALTIME;
skb->tstamp = tstamp;
skb->tstamp_type = SKB_CLOCK_TAI;
break;
default:
return -EINVAL;
@ -9387,16 +9391,17 @@ static struct bpf_insn *bpf_convert_tstamp_type_read(const struct bpf_insn *si,
{
__u8 value_reg = si->dst_reg;
__u8 skb_reg = si->src_reg;
/* AX is needed because src_reg and dst_reg could be the same */
__u8 tmp_reg = BPF_REG_AX;
*insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg,
SKB_BF_MONO_TC_OFFSET);
*insn++ = BPF_JMP32_IMM(BPF_JSET, tmp_reg,
SKB_MONO_DELIVERY_TIME_MASK, 2);
*insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_TSTAMP_UNSPEC);
*insn++ = BPF_JMP_A(1);
*insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_TSTAMP_DELIVERY_MONO);
BUILD_BUG_ON(__SKB_CLOCK_MAX != (int)BPF_SKB_CLOCK_TAI);
BUILD_BUG_ON(SKB_CLOCK_REALTIME != (int)BPF_SKB_CLOCK_REALTIME);
BUILD_BUG_ON(SKB_CLOCK_MONOTONIC != (int)BPF_SKB_CLOCK_MONOTONIC);
BUILD_BUG_ON(SKB_CLOCK_TAI != (int)BPF_SKB_CLOCK_TAI);
*insn++ = BPF_LDX_MEM(BPF_B, value_reg, skb_reg, SKB_BF_MONO_TC_OFFSET);
*insn++ = BPF_ALU32_IMM(BPF_AND, value_reg, SKB_TSTAMP_TYPE_MASK);
#ifdef __BIG_ENDIAN_BITFIELD
*insn++ = BPF_ALU32_IMM(BPF_RSH, value_reg, SKB_TSTAMP_TYPE_RSHIFT);
#else
BUILD_BUG_ON(!(SKB_TSTAMP_TYPE_MASK & 0x1));
#endif
return insn;
}
@ -9439,10 +9444,11 @@ static struct bpf_insn *bpf_convert_tstamp_read(const struct bpf_prog *prog,
__u8 tmp_reg = BPF_REG_AX;
*insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, SKB_BF_MONO_TC_OFFSET);
*insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg,
TC_AT_INGRESS_MASK | SKB_MONO_DELIVERY_TIME_MASK);
*insn++ = BPF_JMP32_IMM(BPF_JNE, tmp_reg,
TC_AT_INGRESS_MASK | SKB_MONO_DELIVERY_TIME_MASK, 2);
/* check if ingress mask bits is set */
*insn++ = BPF_JMP32_IMM(BPF_JSET, tmp_reg, TC_AT_INGRESS_MASK, 1);
*insn++ = BPF_JMP_A(4);
*insn++ = BPF_JMP32_IMM(BPF_JSET, tmp_reg, SKB_TSTAMP_TYPE_MASK, 1);
*insn++ = BPF_JMP_A(2);
/* skb->tc_at_ingress && skb->tstamp_type,
* read 0 as the (rcv) timestamp.
*/
@ -9479,7 +9485,7 @@ static struct bpf_insn *bpf_convert_tstamp_write(const struct bpf_prog *prog,
/* goto <store> */
*insn++ = BPF_JMP_A(2);
/* <clear>: skb->tstamp_type */
*insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, ~SKB_MONO_DELIVERY_TIME_MASK);
*insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, ~SKB_TSTAMP_TYPE_MASK);
*insn++ = BPF_STX_MEM(BPF_B, skb_reg, tmp_reg, SKB_BF_MONO_TC_OFFSET);
}
#endif

View File

@ -1457,7 +1457,10 @@ struct sk_buff *__ip_make_skb(struct sock *sk,
skb->priority = (cork->tos != -1) ? cork->priority: READ_ONCE(sk->sk_priority);
skb->mark = cork->mark;
skb->tstamp = cork->transmit_time;
if (sk_is_tcp(sk))
skb_set_delivery_time(skb, cork->transmit_time, SKB_CLOCK_MONOTONIC);
else
skb_set_delivery_type_by_clockid(skb, cork->transmit_time, sk->sk_clockid);
/*
* Steal rt from cork.dst to avoid a pair of atomic_inc/atomic_dec
* on dst refcount

View File

@ -360,7 +360,7 @@ static int raw_send_hdrinc(struct sock *sk, struct flowi4 *fl4,
skb->protocol = htons(ETH_P_IP);
skb->priority = READ_ONCE(sk->sk_priority);
skb->mark = sockc->mark;
skb->tstamp = sockc->transmit_time;
skb_set_delivery_type_by_clockid(skb, sockc->transmit_time, sk->sk_clockid);
skb_dst_set(skb, &rt->dst);
*rtp = NULL;

View File

@ -3625,6 +3625,8 @@ void __init tcp_v4_init(void)
*/
inet_sk(sk)->pmtudisc = IP_PMTUDISC_DO;
sk->sk_clockid = CLOCK_MONOTONIC;
per_cpu(ipv4_tcp_sk, cpu) = sk;
}
if (register_pernet_subsys(&tcp_sk_ops))

View File

@ -1924,7 +1924,10 @@ struct sk_buff *__ip6_make_skb(struct sock *sk,
skb->priority = READ_ONCE(sk->sk_priority);
skb->mark = cork->base.mark;
skb->tstamp = cork->base.transmit_time;
if (sk_is_tcp(sk))
skb_set_delivery_time(skb, cork->base.transmit_time, SKB_CLOCK_MONOTONIC);
else
skb_set_delivery_type_by_clockid(skb, cork->base.transmit_time, sk->sk_clockid);
ip6_cork_steal_dst(skb, cork);
IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTREQUESTS);

View File

@ -621,7 +621,7 @@ static int rawv6_send_hdrinc(struct sock *sk, struct msghdr *msg, int length,
skb->protocol = htons(ETH_P_IPV6);
skb->priority = READ_ONCE(sk->sk_priority);
skb->mark = sockc->mark;
skb->tstamp = sockc->transmit_time;
skb_set_delivery_type_by_clockid(skb, sockc->transmit_time, sk->sk_clockid);
skb_put(skb, length);
skb_reset_network_header(skb);

View File

@ -2387,8 +2387,14 @@ static struct inet_protosw tcpv6_protosw = {
static int __net_init tcpv6_net_init(struct net *net)
{
return inet_ctl_sock_create(&net->ipv6.tcp_sk, PF_INET6,
SOCK_RAW, IPPROTO_TCP, net);
int res;
res = inet_ctl_sock_create(&net->ipv6.tcp_sk, PF_INET6,
SOCK_RAW, IPPROTO_TCP, net);
if (!res)
net->ipv6.tcp_sk->sk_clockid = CLOCK_MONOTONIC;
return res;
}
static void __net_exit tcpv6_net_exit(struct net *net)

View File

@ -2056,8 +2056,7 @@ retry:
skb->dev = dev;
skb->priority = READ_ONCE(sk->sk_priority);
skb->mark = READ_ONCE(sk->sk_mark);
skb->tstamp = sockc.transmit_time;
skb_set_delivery_type_by_clockid(skb, sockc.transmit_time, sk->sk_clockid);
skb_setup_tx_timestamp(skb, sockc.tsflags);
if (unlikely(extra_len == 4))
@ -2584,7 +2583,7 @@ static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
skb->dev = dev;
skb->priority = READ_ONCE(po->sk.sk_priority);
skb->mark = READ_ONCE(po->sk.sk_mark);
skb->tstamp = sockc->transmit_time;
skb_set_delivery_type_by_clockid(skb, sockc->transmit_time, po->sk.sk_clockid);
skb_setup_tx_timestamp(skb, sockc->tsflags);
skb_zcopy_set_nouarg(skb, ph.raw);
@ -3062,7 +3061,7 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
skb->dev = dev;
skb->priority = READ_ONCE(sk->sk_priority);
skb->mark = sockc.mark;
skb->tstamp = sockc.transmit_time;
skb_set_delivery_type_by_clockid(skb, sockc.transmit_time, sk->sk_clockid);
if (unlikely(extra_len == 4))
skb->no_fcs = 1;

View File

@ -6207,12 +6207,17 @@ union { \
__u64 :64; \
} __attribute__((aligned(8)))
/* The enum used in skb->tstamp_type. It specifies the clock type
* of the time stored in the skb->tstamp.
*/
enum {
BPF_SKB_TSTAMP_UNSPEC,
BPF_SKB_TSTAMP_DELIVERY_MONO, /* tstamp has mono delivery time */
/* For any BPF_SKB_TSTAMP_* that the bpf prog cannot handle,
* the bpf prog should handle it like BPF_SKB_TSTAMP_UNSPEC
* and try to deduce it by ingress, egress or skb->sk->sk_clockid.
BPF_SKB_TSTAMP_UNSPEC = 0, /* DEPRECATED */
BPF_SKB_TSTAMP_DELIVERY_MONO = 1, /* DEPRECATED */
BPF_SKB_CLOCK_REALTIME = 0,
BPF_SKB_CLOCK_MONOTONIC = 1,
BPF_SKB_CLOCK_TAI = 2,
/* For any future BPF_SKB_CLOCK_* that the bpf prog cannot handle,
* the bpf prog can try to deduce it by ingress/egress/skb->sk->sk_clockid.
*/
};