On 5/6/2024 1:50 PM, Abhishek Chauhan (ABC) wrote: > > > On 5/6/2024 12:04 PM, Willem de Bruijn wrote: >> Abhishek Chauhan wrote: >>> With changes in the design to forward CLOCK_TAI in the skbuff >>> framework, existing selftest framework needs modification >>> to handle forwarding of UDP packets with CLOCK_TAI as clockid. >>> >>> Link: https://lore.kernel.org/netdev/bc037db4-58bb-4861-ac31-a361a93841d3@xxxxxxxxx/ >>> Signed-off-by: Abhishek Chauhan <quic_abchauha@xxxxxxxxxxx> >>> --- >>> tools/include/uapi/linux/bpf.h | 15 ++++--- >>> .../selftests/bpf/prog_tests/ctx_rewrite.c | 10 +++-- >>> .../selftests/bpf/prog_tests/tc_redirect.c | 3 -- >>> .../selftests/bpf/progs/test_tc_dtime.c | 39 +++++++++---------- >>> 4 files changed, 34 insertions(+), 33 deletions(-) >>> >>> diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h >>> index 90706a47f6ff..25ea393cf084 100644 >>> --- a/tools/include/uapi/linux/bpf.h >>> +++ b/tools/include/uapi/linux/bpf.h >>> @@ -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. >>> */ >>> }; >>> >>> diff --git a/tools/testing/selftests/bpf/prog_tests/ctx_rewrite.c b/tools/testing/selftests/bpf/prog_tests/ctx_rewrite.c >>> index 3b7c57fe55a5..71940f4ef0fb 100644 >>> --- a/tools/testing/selftests/bpf/prog_tests/ctx_rewrite.c >>> +++ b/tools/testing/selftests/bpf/prog_tests/ctx_rewrite.c >>> @@ -69,15 +69,17 @@ static struct test_case test_cases[] = { >>> { >>> N(SCHED_CLS, struct __sk_buff, tstamp), >>> .read = "r11 = *(u8 *)($ctx + sk_buff::__mono_tc_offset);" >>> - "w11 &= 3;" >>> - "if w11 != 0x3 goto pc+2;" >>> + "if w11 == 0x4 goto pc+1;" >>> + "goto pc+4;" >>> + "if w11 == 0x3 goto pc+1;" >>> + "goto pc+2;" >> >> Not an expert on this code, and I see that the existing code already >> has this below, but: isn't it odd and unnecessary to jump to an >> unconditional jump statement? >> > I am closely looking into your comment and i will evalute it(Martin can correct me > if the jumps are correct or not as i am new to BPF as well) but i found out that > JSET = "&" and not "==". So the above two ins has to change from - > > "if w11 == 0x4 goto pc+1;" ==>(needs to be corrected to) "if w11 & 0x4 goto pc+1;" > "if w11 == 0x3 goto pc+1;" ==> (needs to be correct to) "if w11 & 0x3 goto pc+1;" > > >>> "$dst = 0;" >>> "goto pc+1;" >>> "$dst = *(u64 *)($ctx + sk_buff::tstamp);", >>> .write = "r11 = *(u8 *)($ctx + sk_buff::__mono_tc_offset);" >>> - "if w11 & 0x2 goto pc+1;" >>> + "if w11 & 0x4 goto pc+1;" >>> "goto pc+2;" >>> - "w11 &= -2;" >>> + "w11 &= -3;" > Martin, > Also i am not sure why the the dissembly complains because the value of SKB_TSTAMP_TYPE_MASK = 3 and we are > negating it ~3 = -3. > > Can't match disassembly(left) with pattern(right): > r11 = *(u8 *)(r1 +129) ; r11 = *(u8 *)($ctx + sk_buff::__mono_tc_offset) > if w11 & 0x4 goto pc+1 ; if w11 & 0x4 goto pc+1 > goto pc+2 ; goto pc+2 > w11 &= -4 ; w11 &= -3 > Martin, Please ignore this. It has to -4 and not -3. I figured it out. >>> "*(u8 *)($ctx + sk_buff::__mono_tc_offset) = r11;" >>> "*(u64 *)($ctx + sk_buff::tstamp) = $src;", >>> },
