net: sched: make default fifo qdiscs appear in the dump
authorJiri Kosina <jkosina@suse.cz>
Wed, 8 Mar 2017 15:03:32 +0000 (16:03 +0100)
committerDavid S. Miller <davem@davemloft.net>
Mon, 13 Mar 2017 05:53:02 +0000 (22:53 -0700)
commit49b499718fa1b0d639663cfd03085b9bfd23cdc8
tree7aab59bb529a6fe9e03ff2b5375bade8d559f061
parent5e8456fdd23c23bbfa06e0d647c90758102a4410
net: sched: make default fifo qdiscs appear in the dump

The original reason [1] for having hidden qdiscs (potential scalability
issues in qdisc_match_from_root() with single linked list in case of large
amount of qdiscs) has been invalidated by 59cc1f61f0 ("net: sched: convert
qdisc linked list to hashtable").

This allows us for bringing more clarity and determinism into the dump by
making default pfifo qdiscs visible.

We're not turning this on by default though, at it was deemed [2] too
intrusive / unnecessary change of default behavior towards userspace.
Instead, TCA_DUMP_INVISIBLE netlink attribute is introduced, which allows
applications to request complete qdisc hierarchy dump, including the
ones that have always been implicit/invisible.

Singleton noop_qdisc stays invisible, as teaching the whole infrastructure
about singletons would require quite some surgery with very little gain
(seeing no qdisc or seeing noop qdisc in the dump is probably setting
the same user expectation).

[1] http://lkml.kernel.org/r/1460732328.10638.74.camel@edumazet-glaptop3.roam.corp.google.com
[2] http://lkml.kernel.org/r/20161021.105935.1907696543877061916.davem@davemloft.net

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
18 files changed:
include/net/pkt_sched.h
include/net/sch_generic.h
include/uapi/linux/rtnetlink.h
net/sched/sch_api.c
net/sched/sch_cbq.c
net/sched/sch_drr.c
net/sched/sch_dsmark.c
net/sched/sch_generic.c
net/sched/sch_hfsc.c
net/sched/sch_htb.c
net/sched/sch_mq.c
net/sched/sch_mqprio.c
net/sched/sch_multiq.c
net/sched/sch_prio.c
net/sched/sch_qfq.c
net/sched/sch_red.c
net/sched/sch_sfb.c
net/sched/sch_tbf.c