AF_XDP example: Improvements to wake-up accuracy #36
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Calling tx_pkt() before the link is ready, result in no packets transmitted, but xsk_ring_prod__reserve() still succeeds. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Measurements show that on test systems, clock_nanosleep fairly consistently wakeup later (or after) the requested sleep time. It is fairly trivial to simply adjust the sleep/wakeup time with the measure inaccuracy of clock_nanosleep, and "ask" clock_nanosleep to wakeup a bit earlier. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
This is done to easier visually see the time difference when debug printing the timespec's (via print_timespec). Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
When interval goes below 1 sec this hack screwup first clock_nanosleep. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Give a print WARN if code/AF_XDP somehow have MORE packets to complete from CQ than our counter for xsk->outstanding_tx packets. This should not happen, but currently hunting for a TX issue. The code (below) reset xsk->outstanding_tx, which were introduced via a discussion on xdp-tutorial: xdp-project/xdp-tutorial#180 Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
I hope there exist a better API for determining when AF_XDP is ready for transmitting packets. This workaround keeps trying to send a single packet, and check return value seen from sendto() syscall, until it doesn't return an error. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
…t_adj happened Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
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Measurements show that on test systems, clock_nanosleep fairly consistently wakeup later (or after) the requested sleep time.
In this branch I've been playing with improving on wake-up accuracy for cyclic-TX.
Mainly creating this for @jopbs to notice ;-)