> BPF_CALL_3(bpf_skb_set_tstamp, struct sk_buff *, skb,
> u64, tstamp, u32, tstamp_type)
> {
> /* ... */
> case BPF_SKB_CLOCK_TAI:
> if (!tstamp)
> return -EINVAL;
> skb->tstamp = tstamp;
> skb->tstamp_type = SKB_CLOCK_TAI;
> break;
> case BPF_SKB_CLOCK_REALTIME:
> skb->tstamp = tstamp;
> skb->tstamp_type = SKB_CLOCK_REALTIME;
> break;
>
> /* ... */
> }
>
>> return -EINVAL;
>
>> @@ -9388,17 +9394,17 @@ 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 != BPF_SKB_TSTAMP_DELIVERY_TAI);
>
> Add these also:
>
> BUILD_BUG_ON(SKB_CLOCK_REALTIME != BPF_SKB_CLOCK_REALTIME);
> BUILD_BUG_ON(SKB_CLOCK_MONOTONIC != BPF_SKB_CLOCK_MONOTONIC);
> BUILD_BUG_ON(SKB_CLOCK_TAI != BPF_SKB_CLOCK_TAI);
>
Martin, The above suggestion of adding BUILD_BUG_ON always gives me a warning stating the following.
Some systems considers warning as error if compiler flags are enabled. I believe this requires your suggestion before i raise RFC v6 patchset to either keep the
BUILD_BUG_ON or remove it completely.
/local/mnt/workspace/kernel_master/linux-next/net/core/filter.c:9395:34: warning: comparison between ‘enum skb_tstamp_type’ and ‘enum <anonymous>’ [-Wenum-compare]
9395 | BUILD_BUG_ON(SKB_CLOCK_REALTIME != BPF_SKB_CLOCK_REALTIME);
| ^~
/local/mnt/workspace/kernel_master/linux-next/include/linux/compiler_types.h:451:9: note: in definition of macro ‘__compiletime_assert’
451 | if (!(condition)) \
| ^~~~~~~~~
/local/mnt/workspace/kernel_master/linux-next/include/linux/compiler_types.h:471:2: note: in expansion of macro ‘_compiletime_assert’
471 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
| ^~~~~~~~~~~~~~~~~~~
/local/mnt/workspace/kernel_master/linux-next/include/linux/build_bug.h:39:37: note: in expansion of macro ‘compiletime_assert’
39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
| ^~~~~~~~~~~~~~~~~~
/local/mnt/workspace/kernel_master/linux-next/include/linux/build_bug.h:50:2: note: in expansion of macro ‘BUILD_BUG_ON_MSG’
50 | BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition)
| ^~~~~~~~~~~~~~~~
/local/mnt/workspace/kernel_master/linux-next/net/core/filter.c:9395:2: note: in expansion of macro ‘BUILD_BUG_ON’
9395 | BUILD_BUG_ON(SKB_CLOCK_REALTIME != BPF_SKB_CLOCK_REALTIME);
| ^~~~~~~~~~~~
/local/mnt/workspace/kernel_master/linux-next/net/core/filter.c:9396:35: warning: comparison between ‘enum skb_tstamp_type’ and ‘enum <anonymous>’ [-Wenum-compare]
9396 | BUILD_BUG_ON(SKB_CLOCK_MONOTONIC != BPF_SKB_CLOCK_MONOTONIC);
| ^~
/local/mnt/workspace/kernel_master/linux-next/include/linux/compiler_types.h:451:9: note: in definition of macro ‘__compiletime_assert’
451 | if (!(condition)) \
| ^~~~~~~~~
| ^~
