remarkable-linux/net/sched
Jarek Poplawski 8caf153974 net: sch_netem: Fix an inconsistency in ingress netem timestamps.
Alex Sidorenko reported:

"while experimenting with 'netem' we have found some strange behaviour. It
seemed that ingress delay as measured by 'ping' command shows up on some
hosts but not on others.

After some investigation I have found that the problem is that skbuff->tstamp
field value depends on whether there are any packet sniffers enabled. That
is:

- if any ptype_all handler is registered, the tstamp field is as expected
- if there are no ptype_all handlers, the tstamp field does not show the delay"

This patch prevents unnecessary update of tstamp in dev_queue_xmit_nit()
on ingress path (with act_mirred) adding a check, so minimal overhead on
the fast path, but only when sniffers etc. are active.

Since netem at ingress seems to logically emulate a network before a host,
tstamp is zeroed to trigger the update and pretend delays are from the
outside.

Reported-by: Alex Sidorenko <alexandre.sidorenko@hp.com>
Tested-by: Alex Sidorenko <alexandre.sidorenko@hp.com>
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-20 02:14:59 -07:00
..
act_api.c
act_gact.c
act_ipt.c
act_mirred.c
act_nat.c
act_pedit.c
act_police.c pkt_sched: act_police: Fix a rate estimator test. 2009-03-04 17:38:10 -08:00
act_simple.c
act_skbedit.c
cls_api.c
cls_basic.c
cls_cgroup.c cls_cgroup: clean up for cgroup part 2008-12-29 19:40:45 -08:00
cls_flow.c
cls_fw.c
cls_route.c
cls_rsvp.c
cls_rsvp.h
cls_rsvp6.c
cls_tcindex.c
cls_u32.c pkt_sched: cls_u32: Fix locking in u32_change() 2009-01-05 18:14:19 -08:00
em_cmp.c
em_meta.c netsched: Allow meta match on vlan tag on receive 2009-04-13 18:12:57 -07:00
em_nbyte.c
em_text.c
em_u32.c
ematch.c
Kconfig cls_cgroup: clean up Kconfig 2008-12-29 19:40:46 -08:00
Makefile
sch_api.c pkt_sched: sch_hfsc: sch_htb: Add non-work-conserving warning handler. 2009-02-01 01:12:42 -08:00
sch_atm.c
sch_blackhole.c
sch_cbq.c pkt_sched: Change misleading code in class delete. 2009-03-15 20:00:19 -07:00
sch_drr.c pkt_sched: Change misleading code in class delete. 2009-03-15 20:00:19 -07:00
sch_dsmark.c
sch_fifo.c
sch_generic.c Revert "net: Fix for initial link state in 2.6.28" 2009-01-05 16:01:51 -08:00
sch_gred.c
sch_hfsc.c pkt_sched: Change misleading code in class delete. 2009-03-15 20:00:19 -07:00
sch_htb.c pkt_sched: Change misleading code in class delete. 2009-03-15 20:00:19 -07:00
sch_ingress.c
sch_multiq.c pkt_sched: sch_multiq: Change errno on non-multiqueue devices use. 2009-02-10 00:11:21 -08:00
sch_netem.c net: sch_netem: Fix an inconsistency in ingress netem timestamps. 2009-04-20 02:14:59 -07:00
sch_prio.c
sch_red.c
sch_sfq.c remove lots of double-semicolons 2009-01-08 08:31:14 -08:00
sch_tbf.c net/*: use linux/kernel.h swap() 2009-03-21 13:36:17 -07:00
sch_teql.c sch_teql: convert to net_device_ops 2009-01-06 10:45:57 -08:00