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  1. 25 1月, 2018 2 次提交
  3. 23 1月, 2018 2 次提交
  5. 20 1月, 2018 6 次提交
  7. 18 1月, 2018 1 次提交
  9. 14 12月, 2017 1 次提交
  11. 09 11月, 2017 1 次提交
  13. 04 11月, 2017 1 次提交
  15. 29 10月, 2017 1 次提交
  17. 21 10月, 2017 3 次提交
  19. 20 10月, 2017 1 次提交
  21. 17 10月, 2017 1 次提交
  23. 29 9月, 2017 1 次提交
  25. 01 9月, 2017 1 次提交
    • C
      net_sched: add reverse binding for tc class · 07d79fc7
      由 Cong Wang 提交于 
      TC filters when used as classifiers are bound to TC classes.
However, there is a hidden difference when adding them in different
orders:

1. If we add tc classes before its filters, everything is fine.
   Logically, the classes exist before we specify their ID's in
   filters, it is easy to bind them together, just as in the current
   code base.

2. If we add tc filters before the tc classes they bind, we have to
   do dynamic lookup in fast path. What's worse, this happens all
   the time not just once, because on fast path tcf_result is passed
   on stack, there is no way to propagate back to the one in tc filters.

This hidden difference hurts performance silently if we have many tc
classes in hierarchy.

This patch intends to close this gap by doing the reverse binding when
we create a new class, in this case we can actually search all the
filters in its parent, match and fixup by classid. And because
tcf_result is specific to each type of tc filter, we have to introduce
a new ops for each filter to tell how to bind the class.

Note, we still can NOT totally get rid of those class lookup in
->enqueue() because cgroup and flow filters have no way to determine
the classid at setup time, they still have to go through dynamic lookup.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      07d79fc7
  27. 26 8月, 2017 1 次提交
    • W
      net_sched: kill u32_node pointer in Qdisc · 3cd904ec
      由 WANG Cong 提交于 
      It is ugly to hide a u32-filter-specific pointer inside Qdisc,
this breaks the TC layers:

1. Qdisc is a generic representation, should not have any specific
   data of any type

2. Qdisc layer is above filter layer, should only save filters in
   the list of struct tcf_proto.

This pointer is used as the head of the chain of u32 hash tables,
that is struct tc_u_hnode, because u32 filter is very special,
it allows to create multiple hash tables within one qdisc and
across multiple u32 filters.

Instead of using this ugly pointer, we can just save it in a global
hash table key'ed by (dev ifindex, qdisc handle), therefore we can
still treat it as a per qdisc basis data structure conceptually.

Of course, because of network namespaces, this key is not unique
at all, but it is fine as we already have a pointer to Qdisc in
struct tc_u_common, we can just compare the pointers when collision.

And this only affects slow paths, has no impact to fast path,
thanks to the pointer ->tp_c.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      3cd904ec
  29. 12 8月, 2017 1 次提交
  31. 08 8月, 2017 4 次提交
  33. 05 8月, 2017 1 次提交
  35. 08 6月, 2017 1 次提交
  37. 22 4月, 2017 1 次提交
    • W
      net_sched: move the empty tp check from ->destroy() to ->delete() · 763dbf63
      由 WANG Cong 提交于 
      We could have a race condition where in ->classify() path we
dereference tp->root and meanwhile a parallel ->destroy() makes it
a NULL. Daniel cured this bug in commit d9363774
("net, sched: respect rcu grace period on cls destruction").

This happens when ->destroy() is called for deleting a filter to
check if we are the last one in tp, this tp is still linked and
visible at that time. The root cause of this problem is the semantic
of ->destroy(), it does two things (for non-force case):

1) check if tp is empty
2) if tp is empty we could really destroy it

and its caller, if cares, needs to check its return value to see if it
is really destroyed. Therefore we can't unlink tp unless we know it is
empty.

As suggested by Daniel, we could actually move the test logic to ->delete()
so that we can safely unlink tp after ->delete() tells us the last one is
just deleted and before ->destroy().

Fixes: 1e052be6 ("net_sched: destroy proto tp when all filters are gone")
Cc: Roi Dayan <roid@mellanox.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      763dbf63
  39. 14 4月, 2017 1 次提交
  41. 18 2月, 2017 1 次提交
  43. 10 1月, 2017 1 次提交
  45. 20 9月, 2016 1 次提交
  47. 23 8月, 2016 1 次提交
  49. 09 6月, 2016 2 次提交
  51. 08 6月, 2016 2 次提交