Граф коммитов

192 Коммитов

Автор SHA1 Сообщение Дата
David S. Miller 0dbc81eab4 net: sched: Fix warnings from xchg() on RCU'd cookie pointer.
The kbuild test robot reports:

>> net/sched/act_api.c:71:15: sparse: incorrect type in initializer (different address spaces) @@    expected struct tc_cookie [noderef] <asn:4>*__ret @@    got [noderef] <asn:4>*__ret @@
   net/sched/act_api.c:71:15:    expected struct tc_cookie [noderef] <asn:4>*__ret
   net/sched/act_api.c:71:15:    got struct tc_cookie *new_cookie
>> net/sched/act_api.c:71:13: sparse: incorrect type in assignment (different address spaces) @@    expected struct tc_cookie *old @@    got struct tc_cookie [noderef] <struct tc_cookie *old @@
   net/sched/act_api.c:71:13:    expected struct tc_cookie *old
   net/sched/act_api.c:71:13:    got struct tc_cookie [noderef] <asn:4>*[assigned] __ret
>> net/sched/act_api.c:132:48: sparse: dereference of noderef expression

Handle this in the usual way by force casting away the __rcu annotation
when we are using xchg() on it.

Fixes: eec94fdb04 ("net: sched: use rcu for action cookie update")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-08 17:02:59 +09:00
Vlad Buslov 90b73b77d0 net: sched: change action API to use array of pointers to actions
Act API used linked list to pass set of actions to functions. It is
intrusive data structure that stores list nodes inside action structure
itself, which means it is not safe to modify such list concurrently.
However, action API doesn't use any linked list specific operations on this
set of actions, so it can be safely refactored into plain pointer array.

Refactor action API to use array of pointers to tc_actions instead of
linked list. Change argument 'actions' type of exported action init,
destroy and dump functions.

Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-08 12:42:29 +09:00
Vlad Buslov 0190c1d452 net: sched: atomically check-allocate action
Implement function that atomically checks if action exists and either takes
reference to it, or allocates idr slot for action index to prevent
concurrent allocations of actions with same index. Use EBUSY error pointer
to indicate that idr slot is reserved.

Implement cleanup helper function that removes temporary error pointer from
idr. (in case of error between idr allocation and insertion of newly
created action to specified index)

Refactor all action init functions to insert new action to idr using this
API.

Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-08 12:42:29 +09:00
Vlad Buslov cae422f379 net: sched: use reference counting action init
Change action API to assume that action init function always takes
reference to action, even when overwriting existing action. This is
necessary because action API continues to use action pointer after init
function is done. At this point action becomes accessible for concurrent
modifications, so user must always hold reference to it.

Implement helper put list function to atomically release list of actions
after action API init code is done using them.

Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-08 12:42:29 +09:00
Vlad Buslov 4e8ddd7f17 net: sched: don't release reference on action overwrite
Return from action init function with reference to action taken,
even when overwriting existing action.

Action init API initializes its fourth argument (pointer to pointer to tc
action) to either existing action with same index or newly created action.
In case of existing index(and bind argument is zero), init function returns
without incrementing action reference counter. Caller of action init then
proceeds working with action, without actually holding reference to it.
This means that action could be deleted concurrently.

Change action init behavior to always take reference to action before
returning successfully, in order to protect from concurrent deletion.

Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-08 12:42:29 +09:00
Vlad Buslov 16af606739 net: sched: implement reference counted action release
Implement helper delete function that uses new action ops 'delete', instead
of destroying action directly. This is required so act API could delete
actions by index, without holding any references to action that is being
deleted.

Implement function __tcf_action_put() that releases reference to action and
frees it, if necessary. Refactor action deletion code to use new put
function and not to rely on rtnl lock. Remove rtnl lock assertions that are
no longer needed.

Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-08 12:42:29 +09:00
Vlad Buslov 2a2ea34970 net: sched: implement action API that deletes action by index
Implement new action API function that atomically finds and deletes action
from idr by index. Intended to be used by lockless actions that do not rely
on rtnl lock.

Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-08 12:42:28 +09:00
Vlad Buslov 3f7c72bc42 net: sched: always take reference to action
Without rtnl lock protection it is no longer safe to use pointer to tc
action without holding reference to it. (it can be destroyed concurrently)

Remove unsafe action idr lookup function. Instead of it, implement safe tcf
idr check function that atomically looks up action in idr and increments
its reference and bind counters. Implement both action search and check
using new safe function

Reference taken by idr check is temporal and should not be accounted by
userspace clients (both logically and to preserver current API behavior).
Subtract temporal reference when dumping action to userspace using existing
tca_get_fill function arguments.

Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-08 12:42:28 +09:00
Vlad Buslov 789871bb2a net: sched: implement unlocked action init API
Add additional 'rtnl_held' argument to act API init functions. It is
required to implement actions that need to release rtnl lock before loading
kernel module and reacquire if afterwards.

Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-08 12:42:28 +09:00
Vlad Buslov 036bb44327 net: sched: change type of reference and bind counters
Change type of action reference counter to refcount_t.

Change type of action bind counter to atomic_t.
This type is used to allow decrementing bind counter without testing
for 0 result.

Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-08 12:42:28 +09:00
Vlad Buslov eec94fdb04 net: sched: use rcu for action cookie update
Implement functions to atomically update and free action cookie
using rcu mechanism.

Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-08 12:42:28 +09:00
Vlad Buslov 290aa0ad74 net: sched: don't disable bh when accessing action idr
Initial net_device implementation used ingress_lock spinlock to synchronize
ingress path of device. This lock was used in both process and bh context.
In some code paths action map lock was obtained while holding ingress_lock.
Commit e1e992e52f ("[NET_SCHED] protect action config/dump from irqs")
modified actions to always disable bh, while using action map lock, in
order to prevent deadlock on ingress_lock in softirq. This lock was removed
from net_device, so disabling bh, while accessing action map, is no longer
necessary.

Replace all action idr spinlock usage with regular calls that do not
disable bh.

Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-22 15:34:34 -04:00
David S. Miller c0b458a946 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Minor conflicts in drivers/net/ethernet/mellanox/mlx5/core/en_rep.c,
we had some overlapping changes:

1) In 'net' MLX5E_PARAMS_LOG_{SQ,RQ}_SIZE -->
   MLX5E_REP_PARAMS_LOG_{SQ,RQ}_SIZE

2) In 'net-next' params->log_rq_size is renamed to be
   params->log_rq_mtu_frames.

3) In 'net-next' params->hard_mtu is added.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-01 19:49:34 -04:00
Kirill Tkhai 2f635ceeb2 net: Drop pernet_operations::async
Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-27 13:18:09 -04:00
Craig Dillabaugh 734549eb55 net sched actions: fix dumping which requires several messages to user space
Fixes a bug in the tcf_dump_walker function that can cause some actions
to not be reported when dumping a large number of actions. This issue
became more aggrevated when cookies feature was added. In particular
this issue is manifest when large cookie values are assigned to the
actions and when enough actions are created that the resulting table
must be dumped in multiple batches.

The number of actions returned in each batch is limited by the total
number of actions and the memory buffer size.  With small cookies
the numeric limit is reached before the buffer size limit, which avoids
the code path triggering this bug. When large cookies are used buffer
fills before the numeric limit, and the erroneous code path is hit.

For example after creating 32 csum actions with the cookie
aaaabbbbccccdddd

$ tc actions ls action csum
total acts 26

    action order 0: csum (tcp) action continue
    index 1 ref 1 bind 0
    cookie aaaabbbbccccdddd

    .....

    action order 25: csum (tcp) action continue
    index 26 ref 1 bind 0
    cookie aaaabbbbccccdddd
total acts 6

    action order 0: csum (tcp) action continue
    index 28 ref 1 bind 0
    cookie aaaabbbbccccdddd

    ......

    action order 5: csum (tcp) action continue
    index 32 ref 1 bind 0
    cookie aaaabbbbccccdddd

Note that the action with index 27 is omitted from the report.

Fixes: 4b3550ef53 ("[NET_SCHED]: Use nla_nest_start/nla_nest_end")"
Signed-off-by: Craig Dillabaugh <cdillaba@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-27 10:59:12 -04:00
Davide Caratti affaa0c724 net/sched: remove tcf_idr_cleanup()
tcf_idr_cleanup() is no more used, so remove it.

Suggested-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-23 21:52:19 -04:00
Roman Mashak 4e76e75d6a net sched actions: calculate add/delete event message size
Introduce routines to calculate size of the shared tc netlink attributes
and the full message size including netlink header and tc service header.

Update add/delete action logic to have the size for event messages,
the size is passed to tcf_add_notify() and tcf_del_notify() where the
notification message is being allocated and constructed.

Signed-off-by: Roman Mashak <mrv@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-09 11:25:11 -05:00
Roman Mashak d04e6990c9 net sched actions: update Add/Delete action API with new argument
Introduce a new function argument to carry total attributes size for
correct allocation of skb in event messages.

Signed-off-by: Roman Mashak <mrv@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-09 11:25:11 -05:00
Roman Mashak d143b9e305 net sched actions: corrected extack message
Signed-off-by: Roman Mashak <mrv@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-05 10:19:29 -05:00
Alexander Aring b36201455a net: sched: act: handle extack in tcf_generic_walker
This patch adds extack handling for a common used TC act function
"tcf_generic_walker()" to add an extack message on failures.
The tcf_generic_walker() function can fail if get a invalid command
different than DEL and GET. The naming "action" here is wrong, the
correct naming would be command.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 16:05:50 -05:00
Alexander Aring 417801055b net: sched: act: add extack for walk callback
This patch adds extack support for act walker callback api. This
prepares to handle extack support inside each specific act
implementation.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 16:05:50 -05:00
Alexander Aring 331a9295de net: sched: act: add extack for lookup callback
This patch adds extack support for act lookup callback api. This
prepares to handle extack support inside each specific act
implementation.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 16:05:03 -05:00
Alexander Aring 589dad6d71 net: sched: act: add extack to init callback
This patch adds extack support for act init callback api. This
prepares to handle extack support inside each specific act
implementation.

Based on work by David Ahern <dsahern@gmail.com>

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 16:05:03 -05:00
Alexander Aring 84ae017a00 net: sched: act: handle generic action errors
This patch adds extack support for generic act handling. The extack
will be set deeper to each called function which is not part of netdev
core api.

Based on work by David Ahern <dsahern@gmail.com>

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 16:05:02 -05:00
Alexander Aring aea0d72789 net: sched: act: add extack to init
This patch adds extack to tcf_action_init and tcf_action_init_1
functions. These are necessary to make individual extack handling in
each act implementation.

Based on work by David Ahern <dsahern@gmail.com>

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 16:04:53 -05:00
Alexander Aring 1af8515581 net: sched: act: fix code style
This patch is used by subsequent patches. It fixes code style issues
caught by checkpatch.

Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 16:04:53 -05:00
David S. Miller ee99b2d8bf net: Revert sched action extack support series.
It was mis-applied and the changes had rejects.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 16:03:39 -05:00
Alexander Aring 10defbd29e net: sched: act: add extack to init
This patch adds extack to tcf_action_init and tcf_action_init_1
functions. These are necessary to make individual extack handling in
each act implementation.

Based on work by David Ahern <dsahern@gmail.com>

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 15:44:42 -05:00
Alexander Aring b7b347fa3c net: sched: act: fix code style
This patch is used by subsequent patches. It fixes code style issues
caught by checkpatch.

Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 15:44:41 -05:00
Davide Caratti 66dede2d6b net: sched: fix unbalance in the error path of tca_action_flush()
When tca_action_flush() calls the action walk() and gets an error,
a successful call to nla_nest_start() is not followed by a call to
nla_nest_cancel(). It's harmless, as the skb is freed in the error
path - but it's worth to fix this unbalance.

Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 15:43:17 -05:00
Kirill Tkhai 13da199c38 net: Convert subsys_initcall() registered pernet_operations from net/sched
psched_net_ops only creates and destroyes /proc entry,
and safe to be executed in parallel with any foreigh
pernet_operations.

tcf_action_net_ops initializes and destructs tcf_action_net::egdev_ht,
which is not touched by foreign pernet_operations.

So, make them async.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-13 10:36:07 -05:00
Matthew Wilcox 7a4575778f idr: Rename idr_for_each_entry_ext
Most places in the kernel that we need to distinguish functions by the
type of their arguments, we use '_ul' as a suffix for the unsigned long
variant, not '_ext'.  Also add kernel-doc.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
2018-02-06 16:41:28 -05:00
Matthew Wilcox 339913a8be net sched actions: Convert to use idr_alloc_u32
Use the new helper.  Also untangle the error path, and in so doing
noticed that estimator generator failure would lead to us leaking an
ID.  Fix that bug.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
2018-02-06 16:40:33 -05:00
Matthew Wilcox 322d884ba7 idr: Delete idr_find_ext function
Simply changing idr_remove's 'id' argument to 'unsigned long' works
for all callers.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
2018-02-06 16:40:32 -05:00
Matthew Wilcox 234a4624ef idr: Delete idr_replace_ext function
Changing idr_replace's 'id' argument to 'unsigned long' works for all
callers.  Callers which passed a negative ID now get -ENOENT instead of
-EINVAL.  No callers relied on this error value.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
2018-02-06 16:40:31 -05:00
Matthew Wilcox 9c16094140 idr: Delete idr_remove_ext function
Simply changing idr_remove's 'id' argument to 'unsigned long' suffices
for all callers.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
2018-02-06 16:40:31 -05:00
Cong Wang 9a63b255df net_sched: remove unused parameter from act cleanup ops
No one actually uses it.

Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-05 18:07:58 -05:00
David S. Miller 4dc6758d78 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Simple cases of overlapping changes in the packet scheduler.

Must easier to resolve this time.

Which probably means that I screwed it up somehow.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-10 10:00:18 +09:00
Cong Wang c7e460ce55 Revert "net_sched: hold netns refcnt for each action"
This reverts commit ceffcc5e25.
If we hold that refcnt, the netns can never be destroyed until
all actions are destroyed by user, this breaks our netns design
which we expect all actions are destroyed when we destroy the
whole netns.

Cc: Lucas Bates <lucasb@mojatatu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-09 10:03:09 +09:00
David S. Miller 2a171788ba Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Files removed in 'net-next' had their license header updated
in 'net'.  We take the remove from 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-04 09:26:51 +09:00
Cong Wang ceffcc5e25 net_sched: hold netns refcnt for each action
TC actions have been destroyed asynchronously for a long time,
previously in a RCU callback and now in a workqueue. If we
don't hold a refcnt for its netns, we could use the per netns
data structure, struct tcf_idrinfo, after it has been freed by
netns workqueue.

Hold refcnt to ensure netns destroy happens after all actions
are gone.

Fixes: ddf97ccdd7 ("net_sched: add network namespace support for tc actions")
Reported-by: Lucas Bates <lucasb@mojatatu.com>
Tested-by: Lucas Bates <lucasb@mojatatu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-03 10:30:38 +09:00
Cong Wang a159d3c4b8 net_sched: acquire RTNL in tc_action_net_exit()
I forgot to acquire RTNL in tc_action_net_exit()
which leads that action ops->cleanup() is not always
called with RTNL. This usually is not a big deal because
this function is called after all netns refcnt are gone,
but given RTNL protects more than just actions, add it
for safety and consistency.

Also add an assertion to catch other potential bugs.

Fixes: ddf97ccdd7 ("net_sched: add network namespace support for tc actions")
Reported-by: Lucas Bates <lucasb@mojatatu.com>
Tested-by: Lucas Bates <lucasb@mojatatu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-03 10:30:38 +09:00
Or Gerlitz 0843c092ee net/sched: Set the net-device for egress device instance
Currently the netdevice field is not set and the egdev instance
is not functional, fix that.

Fixes: 3f55bdda8df ('net: sched: introduce per-egress action device callbacks')
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-20 13:09:35 +01:00
Jiri Pirko b3f55bdda8 net: sched: introduce per-egress action device callbacks
Introduce infrastructure that allows drivers to register callbacks that
are called whenever tc would offload inserted rule and specified device
acts as tc action egress device.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-11 20:15:43 -07:00
Jiri Pirko 255cd50f20 net: sched: fix use-after-free in tcf_action_destroy and tcf_del_walker
Recent commit d7fb60b9ca ("net_sched: get rid of tcfa_rcu") removed
freeing in call_rcu, which changed already existing hard-to-hit
race condition into 100% hit:

[  598.599825] BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
[  598.607782] IP: tcf_action_destroy+0xc0/0x140

Or:

[   40.858924] BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
[   40.862840] IP: tcf_generic_walker+0x534/0x820

Fix this by storing the ops and use them directly for module_put call.

Fixes: a85a970af2 ("net_sched: move tc_action into tcf_common")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-13 09:34:08 -07:00
Cong Wang d7fb60b9ca net_sched: get rid of tcfa_rcu
gen estimator has been rewritten in commit 1c0d32fde5
("net_sched: gen_estimator: complete rewrite of rate estimators"),
the caller is no longer needed to wait for a grace period.
So this patch gets rid of it.

This also completely closes a race condition between action free
path and filter chain add/remove path for the following patch.
Because otherwise the nested RCU callback can't be caught by
rcu_barrier().

Please see also the comments in code.

Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-12 20:41:02 -07:00
Jakub Kicinski 2c8468dcf8 net: sched: don't use GFP_KERNEL under spin lock
The new TC IDR code uses GFP_KERNEL under spin lock.  Which leads
to:

[  582.621091] BUG: sleeping function called from invalid context at ../mm/slab.h:416
[  582.629721] in_atomic(): 1, irqs_disabled(): 0, pid: 3379, name: tc
[  582.636939] 2 locks held by tc/3379:
[  582.641049]  #0:  (rtnl_mutex){+.+.+.}, at: [<ffffffff910354ce>] rtnetlink_rcv_msg+0x92e/0x1400
[  582.650958]  #1:  (&(&tn->idrinfo->lock)->rlock){+.-.+.}, at: [<ffffffff9110a5e0>] tcf_idr_create+0x2f0/0x8e0
[  582.662217] Preemption disabled at:
[  582.662222] [<ffffffff9110a5e0>] tcf_idr_create+0x2f0/0x8e0
[  582.672592] CPU: 9 PID: 3379 Comm: tc Tainted: G        W       4.13.0-rc7-debug-00648-g43503a79b9f0 #287
[  582.683432] Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS 2.3.4 11/08/2016
[  582.691937] Call Trace:
...
[  582.742460]  kmem_cache_alloc+0x286/0x540
[  582.747055]  radix_tree_node_alloc.constprop.6+0x4a/0x450
[  582.753209]  idr_get_free_cmn+0x627/0xf80
...
[  582.815525]  idr_alloc_cmn+0x1a8/0x270
...
[  582.833804]  tcf_idr_create+0x31b/0x8e0
...

Try to preallocate the memory with idr_prealloc(GFP_KERNEL)
(as suggested by Eric Dumazet), and change the allocation
flags under spin lock.

Fixes: 65a206c01e ("net/sched: Change act_api and act_xxx modules to use IDR")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-05 14:48:29 -07:00
Chris Mi 65a206c01e net/sched: Change act_api and act_xxx modules to use IDR
Typically, each TC filter has its own action. All the actions of the
same type are saved in its hash table. But the hash buckets are too
small that it degrades to a list. And the performance is greatly
affected. For example, it takes about 0m11.914s to insert 64K rules.
If we convert the hash table to IDR, it only takes about 0m1.500s.
The improvement is huge.

But please note that the test result is based on previous patch that
cls_flower uses IDR.

Signed-off-by: Chris Mi <chrism@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-30 14:38:51 -07:00
Florian Westphal b97bac64a5 rtnetlink: make rtnl_register accept a flags parameter
This change allows us to later indicate to rtnetlink core that certain
doit functions should be called without acquiring rtnl_mutex.

This change should have no effect, we simply replace the last (now
unused) calcit argument with the new flag.

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-09 16:57:38 -07:00
Jiri Pirko ec1a9cca0e net: sched: remove check for number of actions in tcf_exts_exec
Leave it to tcf_action_exec to return TC_ACT_OK in case there is no
action present.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-04 11:21:23 -07:00