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  1. Jul 26, 2016
  3. Jun 15, 2016
  5. Jun 07, 2016
  7. May 20, 2016
    • Arnd Bergmann's avatar
      mlx5: avoid unused variable warning · e6790fd8
      Arnd Bergmann authored 
      

When CONFIG_NET_CLS_ACT is disabled, we get a new warning in the mlx5
ethernet driver because the tc_for_each_action() loop never references
the iterator:

mellanox/mlx5/core/en_tc.c: In function 'mlx5e_stats_flower':
mellanox/mlx5/core/en_tc.c:431:20: error: unused variable 'a' [-Werror=unused-variable]
  struct tc_action *a;

This changes the dummy tc_for_each_action() macro by adding a
cast to void, letting the compiler know that the variable is
intentionally declared but not used here. I could not come up
with a nicer workaround, but this seems to do the trick.

Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Fixes: aad7e08d ("net/mlx5e: Hardware offloaded flower filter statistics support")
Fixes: 00175aec ("net/sched: Macro instead of CONFIG_NET_CLS_ACT ifdef")
Acked-By: default avatarAmir Vadai <amir@vadai.me>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e6790fd8
  9. May 16, 2016
  11. Apr 06, 2016
  13. Mar 10, 2016
  15. Feb 25, 2016
  17. Aug 26, 2015
  19. Jul 30, 2015
    • Daniel Borkmann's avatar
      net: sched: fix refcount imbalance in actions · 28e6b67f
      Daniel Borkmann authored 
      

Since commit 55334a5d ("net_sched: act: refuse to remove bound action
outside"), we end up with a wrong reference count for a tc action.

Test case 1:

  FOO="1,6 0 0 4294967295,"
  BAR="1,6 0 0 4294967294,"
  tc filter add dev foo parent 1: bpf bytecode "$FOO" flowid 1:1 \
     action bpf bytecode "$FOO"
  tc actions show action bpf
    action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe
    index 1 ref 1 bind 1
  tc actions replace action bpf bytecode "$BAR" index 1
  tc actions show action bpf
    action order 0: bpf bytecode '1,6 0 0 4294967294' default-action pipe
    index 1 ref 2 bind 1
  tc actions replace action bpf bytecode "$FOO" index 1
  tc actions show action bpf
    action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe
    index 1 ref 3 bind 1

Test case 2:

  FOO="1,6 0 0 4294967295,"
  tc filter add dev foo parent 1: bpf bytecode "$FOO" flowid 1:1 action ok
  tc actions show action gact
    action order 0: gact action pass
    random type none pass val 0
     index 1 ref 1 bind 1
  tc actions add action drop index 1
    RTNETLINK answers: File exists [...]
  tc actions show action gact
    action order 0: gact action pass
     random type none pass val 0
     index 1 ref 2 bind 1
  tc actions add action drop index 1
    RTNETLINK answers: File exists [...]
  tc actions show action gact
    action order 0: gact action pass
     random type none pass val 0
     index 1 ref 3 bind 1

What happens is that in tcf_hash_check(), we check tcf_common for a given
index and increase tcfc_refcnt and conditionally tcfc_bindcnt when we've
found an existing action. Now there are the following cases:

  1) We do a late binding of an action. In that case, we leave the
     tcfc_refcnt/tcfc_bindcnt increased and are done with the ->init()
     handler. This is correctly handeled.

  2) We replace the given action, or we try to add one without replacing
     and find out that the action at a specific index already exists
     (thus, we go out with error in that case).

In case of 2), we have to undo the reference count increase from
tcf_hash_check() in the tcf_hash_check() function. Currently, we fail to
do so because of the 'tcfc_bindcnt > 0' check which bails out early with
an -EPERM error.

Now, while commit 55334a5d prevents 'tc actions del action ...' on an
already classifier-bound action to drop the reference count (which could
then become negative, wrap around etc), this restriction only accounts for
invocations outside a specific action's ->init() handler.

One possible solution would be to add a flag thus we possibly trigger
the -EPERM ony in situations where it is indeed relevant.

After the patch, above test cases have correct reference count again.

Fixes: 55334a5d ("net_sched: act: refuse to remove bound action outside")
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Reviewed-by: default avatarCong Wang <cwang@twopensource.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      28e6b67f
  21. Jul 08, 2015
  23. Feb 13, 2014
  25. Jan 21, 2014
  27. Jan 20, 2014
  29. Jan 13, 2014
  31. Jan 02, 2014
  33. Dec 18, 2013
  35. Aug 01, 2013
  37. Jun 11, 2013
    • Eric Dumazet's avatar
      net_sched: add 64bit rate estimators · 45203a3b
      Eric Dumazet authored 
      

struct gnet_stats_rate_est contains u32 fields, so the bytes per second
field can wrap at 34360Mbit.

Add a new gnet_stats_rate_est64 structure to get 64bit bps/pps fields,
and switch the kernel to use this structure natively.

This structure is dumped to user space as a new attribute :

TCA_STATS_RATE_EST64

Old tc command will now display the capped bps (to 34360Mbit), instead
of wrapped values, and updated tc command will display correct
information.

Old tc command output, after patch :

eric:~# tc -s -d qd sh dev lo
qdisc pfifo 8001: root refcnt 2 limit 1000p
 Sent 80868245400 bytes 1978837 pkt (dropped 0, overlimits 0 requeues 0)
 rate 34360Mbit 189696pps backlog 0b 0p requeues 0

This patch carefully reorganizes "struct Qdisc" layout to get optimal
performance on SMP.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      45203a3b
  39. Feb 12, 2013
  41. Jan 14, 2013
  43. Jul 06, 2011
  45. Jun 12, 2010
    • Eric Dumazet's avatar
      pkt_sched: gen_kill_estimator() rcu fixes · c7de2cf0
      Eric Dumazet authored 
      

gen_kill_estimator() API is incomplete or not well documented, since
caller should make sure an RCU grace period is respected before
freeing stats_lock.

This was partially addressed in commit 5d944c64
(gen_estimator: deadlock fix), but same problem exist for all
gen_kill_estimator() users, if lock they use is not already RCU
protected.

A code review shows xt_RATEEST.c, act_api.c, act_police.c have this
problem. Other are ok because they use qdisc lock, already RCU
protected.

Signed-off-by: default avatarEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      c7de2cf0
  47. Aug 18, 2009
  49. Jan 28, 2008