On 5/6/2024 12:00 PM, Willem de Bruijn wrote: > 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> >> --- >> Changes since v5 >> - Took care of documentation comments of tstamp_type >> in skbuff.h as mentioned by Willem. >> - Use of complete words instead of abbrevation in >> macro definitions as mentioned by Willem. >> - Fixed indentation problems >> - Removed BPF_SKB_TSTAMP_UNSPEC and marked it >> Deprecated as documentation, and introduced >> BPF_SKB_CLOCK_REALTIME instead. >> - BUILD_BUG_ON for additional enums introduced. >> - __ip_make_skb and ip6_make_skb now has >> tcp checks to mark tcp packet as mono tstamp base. >> - separated the selftests/bpf changes into another patch. >> - Made changes as per Martin in selftest bpf code and >> tool/include/uapi/linux/bpf.h >> >> Changes since v4 >> - Made changes to BPF code in filter.c as per >> Martin's comments >> - Minor fixes on comments given on documentation >> from Willem in skbuff.h (removed obvious ones) >> - Made changes to ctx_rewrite.c and test_tc_dtime.c >> - test_tc_dtime.c i am not really sure if i took care >> of all the changes as i am not too familiar with >> the framework. >> - Introduce common mask SKB_TSTAMP_TYPE_MASK instead >> of multiple SKB mask. >> - Optimisation on BPF code as suggested by Martin. >> - Set default case to SKB_CLOCK_REALTME. >> >> Changes since v3 >> - Carefully reviewed BPF APIs and made changes in >> BPF code as well. >> - Re-used actual clockid_t values since skbuff.h >> indirectly includes uapi/linux/time.h >> - Added CLOCK_TAI as part of the skb_set_delivery_time >> handling instead of CLOCK_USER >> - Added default in switch for unsupported and invalid >> timestamp with an WARN_ONCE >> - All of the above comments were given by Willem >> - Made changes in filter.c as per Martin's comments >> to handle invalid cases in bpf code with addition of >> SKB_TAI_DELIVERY_TIME_MASK >> >> Changes since v2 >> - Minor changes to commit subject >> >> Changes since v1 >> - identified additional changes in BPF framework. >> - Bit shift in SKB_MONO_DELIVERY_TIME_MASK and TC_AT_INGRESS_MASK. >> - Made changes in skb_set_delivery_time to keep changes similar to >> previous code for mono_delivery_time and just setting tstamp_type >> bit 1 for userspace timestamp. >> >> >> include/linux/skbuff.h | 21 +++++++++++-------- >> include/uapi/linux/bpf.h | 15 +++++++++----- >> net/core/filter.c | 44 +++++++++++++++++++++++----------------- >> net/ipv4/ip_output.c | 5 ++++- >> net/ipv4/raw.c | 2 +- >> net/ipv6/ip6_output.c | 5 ++++- >> net/ipv6/raw.c | 2 +- >> net/packet/af_packet.c | 7 +++---- >> 8 files changed, 61 insertions(+), 40 deletions(-) >> >> diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h >> index de3915e2bfdb..fe7d8dbef77e 100644 >> --- a/include/linux/skbuff.h >> +++ b/include/linux/skbuff.h >> @@ -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, >> }; >> >> /** >> @@ -829,8 +831,7 @@ enum skb_tstamp_type { >> * @decrypted: Decrypted SKB >> * @slow_gro: state present at GRO time, slower prepare step required >> * @tstamp_type: When set, skb->tstamp has the >> - * delivery_time in mono clock base Otherwise, the >> - * timestamp is considered real clock base. >> + * delivery_time clock base of skb->tstamp. >> * @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. >> @@ -958,7 +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; >> @@ -1088,15 +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) >> >> @@ -4213,6 +4215,9 @@ 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; >> diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h >> index 90706a47f6ff..25ea393cf084 100644 >> --- a/include/uapi/linux/bpf.h >> +++ b/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/net/core/filter.c b/net/core/filter.c >> index a3781a796da4..9f3df4a0d1ee 100644 >> --- a/net/core/filter.c >> +++ b/net/core/filter.c >> @@ -7726,16 +7726,20 @@ 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_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 = tstamp; >> + skb->tstamp_type = SKB_CLOCK_TAI; >> + break; >> + case BPF_SKB_CLOCK_REALTIME: >> + skb->tstamp = tstamp; >> skb->tstamp_type = SKB_CLOCK_REALTIME; > > Only since there is another reason to respin. > > The previous code did not do this, but let's order cases by their enum > value, starting with realtime. > > Also in anticipation with possible future expansions. > Noted I will take care of this. >
