Abhishek Chauhan wrote: > 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 exisiting support CLOCK_MONOTONIC and CLOCK_REALTIME. > > Link: https://lore.kernel.org/netdev/bc037db4-58bb-4861-ac31-a361a93841d3@xxxxxxxxx/ > Signed-off-by: Abhishek Chauhan <quic_abchauha@xxxxxxxxxxx> > > /** > - * tstamp_type:1 can take 2 values each > + * tstamp_type:2 can take 4 values each > * represented by time base in skb > * 0x0 => real timestamp_type > * 0x1 => mono timestamp_type > + * 0x2 => tai timestamp_type > + * 0x3 => undefined timestamp_type Same point as previous patch about comment that repeats name. > @@ -833,7 +836,8 @@ enum skb_tstamp_type { > * @tstamp_type: When set, skb->tstamp has the > * delivery_time in mono clock base (i.e. EDT). Otherwise, the > * skb->tstamp has the (rcv) timestamp at ingress and > - * delivery_time at egress. > + * delivery_time at egress or skb->tstamp defined by skb->sk->sk_clockid > + * coming from userspace I would simplify the comment: clock base of skb->tstamp. Already in the first patch. > * @napi_id: id of the NAPI struct this skb came from > * @sender_cpu: (aka @napi_id) source CPU in XPS > * @alloc_cpu: CPU which did the skb allocation. > @@ -961,7 +965,7 @@ struct sk_buff { > /* private: */ > __u8 __mono_tc_offset[0]; > /* public: */ > - __u8 tstamp_type:1; /* See SKB_CLOCK_*_MASK */ > + __u8 tstamp_type:2; /* See skb_tstamp_type enum */ Probably good to call out that according to pahole this fills a hole. > #ifdef CONFIG_NET_XGRESS > __u8 tc_at_ingress:1; /* See TC_AT_INGRESS_MASK */ > __u8 tc_skip_classify:1; > @@ -1096,10 +1100,12 @@ struct sk_buff { > */ > #ifdef __BIG_ENDIAN_BITFIELD > #define SKB_MONO_DELIVERY_TIME_MASK (1 << 7) > -#define TC_AT_INGRESS_MASK (1 << 6) > +#define SKB_TAI_DELIVERY_TIME_MASK (1 << 6) SKB_TSTAMP_TYPE_BIT2_MASK? > +#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_TAI_DELIVERY_TIME_MASK (1 << 1) > +#define TC_AT_INGRESS_MASK (1 << 2) > #endif > #define SKB_BF_MONO_TC_OFFSET offsetof(struct sk_buff, __mono_tc_offset) > > @@ -4206,6 +4212,11 @@ static inline void skb_set_delivery_time(struct sk_buff *skb, ktime_t kt, > case CLOCK_MONOTONIC: > skb->tstamp_type = SKB_CLOCK_MONO; > break; > + case CLOCK_TAI: > + skb->tstamp_type = SKB_CLOCK_TAI; > + break; > + default: > + WARN_ONCE(true, "clockid %d not supported", tstamp_type); and set to 0 and default tstamp_type? > } > } > > @@ -9372,10 +9378,16 @@ static struct bpf_insn *bpf_convert_tstamp_type_read(const struct bpf_insn *si, > *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); > + SKB_MONO_DELIVERY_TIME_MASK | SKB_TAI_DELIVERY_TIME_MASK, 2); > + *insn++ = BPF_JMP32_IMM(BPF_JSET, tmp_reg, > + SKB_MONO_DELIVERY_TIME_MASK, 3); > + *insn++ = BPF_JMP32_IMM(BPF_JSET, tmp_reg, > + SKB_TAI_DELIVERY_TIME_MASK, 4); > *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); > + *insn++ = BPF_JMP_A(1); > + *insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_TSTAMP_DELIVERY_TAI); > > return insn; > } > @@ -9418,10 +9430,26 @@ 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); > + /*check if all three bits are set*/ > *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); > + TC_AT_INGRESS_MASK | SKB_MONO_DELIVERY_TIME_MASK | > + SKB_TAI_DELIVERY_TIME_MASK); > + /*if all 3 bits are set jump 3 instructions and clear the register */ > + *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, > + TC_AT_INGRESS_MASK | SKB_MONO_DELIVERY_TIME_MASK | > + SKB_TAI_DELIVERY_TIME_MASK, 4); > + /*Now check Mono is set with ingress mask if so clear */ > + *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, > + TC_AT_INGRESS_MASK | SKB_MONO_DELIVERY_TIME_MASK, 3); > + /*Now Check tai is set with ingress mask if so clear */ > + *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, > + TC_AT_INGRESS_MASK | SKB_TAI_DELIVERY_TIME_MASK, 2); > + /*Now Check tai and mono are set if so clear */ > + *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, > + SKB_MONO_DELIVERY_TIME_MASK | > + SKB_TAI_DELIVERY_TIME_MASK, 1); This looks as if all JEQ result in "if so clear"? Is the goal to only do something different for the two bits being 0x1, can we have a single test with a two-bit mask, rather than four tests?
