On 4/18/2024 11:47 AM, Willem de Bruijn wrote: > Abhishek Chauhan wrote: >> mono_delivery_time was added to check if skb->tstamp has delivery >> time in mono clock base (i.e. EDT) otherwise skb->tstamp has >> timestamp in ingress and delivery_time at egress. >> >> Renaming the bitfield from mono_delivery_time to tstamp_type is for >> extensibilty for other timestamps such as userspace timestamp >> (i.e. SO_TXTIME) set via sock opts. >> >> As we are renaming the mono_delivery_time to tstamp_type, it makes >> sense to start assigning tstamp_type based on enum defined >> in this commit. >> >> Earlier we used bool arg flag to check if the tstamp is mono in >> function skb_set_delivery_time, Now the signature of the functions >> accepts tstamp_type to distinguish between mono and real time. >> >> In future tstamp_type:1 can be extended to support userspace timestamp >> by increasing the bitfield. >> >> 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 >> + * represented by time base in skb >> + * 0x0 => real timestamp_type >> + * 0x1 => mono timestamp_type >> + */ >> +enum skb_tstamp_type { >> + SKB_CLOCK_REAL, /* Time base is skb is REALTIME */ >> + SKB_CLOCK_MONO, /* Time base is skb is MONOTONIC */ >> +}; >> + > > Can drop the comments. These names are self documenting. Noted! . I will take care of this > >> /** >> * DOC: Basic sk_buff geometry >> * >> @@ -819,7 +830,7 @@ typedef unsigned char *sk_buff_data_t; >> * @dst_pending_confirm: need to confirm neighbour >> * @decrypted: Decrypted SKB >> * @slow_gro: state present at GRO time, slower prepare step required >> - * @mono_delivery_time: When set, skb->tstamp has the >> + * @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. > > Is this still correct? I think all egress does now annotate correctly > as SKB_CLOCK_MONO. So when not set it always is SKB_CLOCK_REAL. > That is correct. >> diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c >> index 61119d42b0fd..a062f88c47c3 100644 >> --- a/net/ipv4/tcp_output.c >> +++ b/net/ipv4/tcp_output.c >> @@ -1300,7 +1300,7 @@ static int __tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, >> tp = tcp_sk(sk); >> prior_wstamp = tp->tcp_wstamp_ns; >> tp->tcp_wstamp_ns = max(tp->tcp_wstamp_ns, tp->tcp_clock_cache); >> - skb_set_delivery_time(skb, tp->tcp_wstamp_ns, true); >> + skb_set_delivery_time(skb, tp->tcp_wstamp_ns, CLOCK_MONOTONIC); > > Multiple references to CLOCK_MONOTONIC left > I think i took care of all the references. Apologies if i didn't understand your comment here. > >
