From: Vlad Buslov <vladbu@mellanox.com>
To: Jiri Pirko <jiri@resnulli.us>
Cc: netdev@vger.kernel.org, davem@davemloft.net, jhs@mojatatu.com,
xiyou.wangcong@gmail.com, pablo@netfilter.org,
kadlec@blackhole.kfki.hu, fw@strlen.de, ast@kernel.org,
daniel@iogearbox.net, edumazet@google.com, keescook@chromium.org,
linux-kernel@vger.kernel.org, netfilter-devel@vger.kernel.org,
coreteam@netfilter.org, kliteyn@mellanox.com
Subject: Re: [PATCH 05/14] net: sched: always take reference to action
Date: Mon, 14 May 2018 21:49:07 +0300 [thread overview]
Message-ID: <vbftvradqe4.fsf@reg-r-vrt-018-180.mtr.labs.mlnx> (raw)
In-Reply-To: <20180514162301.GC2134@nanopsycho.orion>
On Mon 14 May 2018 at 16:23, Jiri Pirko <jiri@resnulli.us> wrote:
> Mon, May 14, 2018 at 04:27:06PM CEST, vladbu@mellanox.com wrote:
>>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.
>>
>>Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
>>---
>> net/sched/act_api.c | 38 ++++++++++++++++----------------------
>> 1 file changed, 16 insertions(+), 22 deletions(-)
>>
>>diff --git a/net/sched/act_api.c b/net/sched/act_api.c
>>index 1331beb..9459cce 100644
>>--- a/net/sched/act_api.c
>>+++ b/net/sched/act_api.c
>>@@ -284,44 +284,38 @@ int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
>> }
>> EXPORT_SYMBOL(tcf_generic_walker);
>>
>>-static struct tc_action *tcf_idr_lookup(u32 index, struct tcf_idrinfo *idrinfo)
>>+bool __tcf_idr_check(struct tc_action_net *tn, u32 index, struct tc_action **a,
>>+ int bind)
>> {
>>- struct tc_action *p = NULL;
>>+ struct tcf_idrinfo *idrinfo = tn->idrinfo;
>>+ struct tc_action *p;
>>
>> spin_lock_bh(&idrinfo->lock);
>
> Why "_bh" variant is necessary here?
It is not my code.
>
>> p = idr_find(&idrinfo->action_idr, index);
>>+ if (p) {
>>+ refcount_inc(&p->tcfa_refcnt);
>>+ if (bind)
>>+ atomic_inc(&p->tcfa_bindcnt);
>>+ }
>> spin_unlock_bh(&idrinfo->lock);
>
> [...]
next prev parent reply other threads:[~2018-05-14 18:49 UTC|newest]
Thread overview: 86+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-05-14 14:27 [PATCH 00/14] Modify action API for implementing lockless actions Vlad Buslov
2018-05-14 14:27 ` [PATCH 01/14] net: sched: use rcu for action cookie update Vlad Buslov
2018-05-14 15:10 ` Jiri Pirko
2018-05-14 23:39 ` kbuild test robot
2018-05-14 14:27 ` [PATCH 02/14] net: sched: change type of reference and bind counters Vlad Buslov
2018-05-14 15:11 ` Jiri Pirko
2018-05-19 21:04 ` Marcelo Ricardo Leitner
2018-05-20 10:55 ` Vlad Buslov
2018-05-14 14:27 ` [PATCH 03/14] net: sched: add 'delete' function to action ops Vlad Buslov
2018-05-14 15:12 ` Jiri Pirko
2018-05-14 16:30 ` Jiri Pirko
2018-05-14 14:27 ` [PATCH 04/14] net: sched: implement unlocked action init API Vlad Buslov
2018-05-14 15:16 ` Jiri Pirko
2018-05-19 21:11 ` Marcelo Ricardo Leitner
2018-05-14 14:27 ` [PATCH 05/14] net: sched: always take reference to action Vlad Buslov
2018-05-14 16:23 ` Jiri Pirko
2018-05-14 18:49 ` Vlad Buslov [this message]
2018-05-15 8:58 ` Jiri Pirko
2018-05-15 11:52 ` Vlad Buslov
2018-05-15 1:38 ` kbuild test robot
2018-05-15 1:38 ` [RFC PATCH] net: sched: __tcf_idr_check() can be static kbuild test robot
2018-05-14 14:27 ` [PATCH 06/14] net: sched: implement reference counted action release Vlad Buslov
2018-05-14 16:28 ` Jiri Pirko
2018-05-14 16:47 ` Jiri Pirko
2018-05-14 19:07 ` Vlad Buslov
2018-05-15 9:03 ` Jiri Pirko
2018-05-15 9:16 ` Vlad Buslov
2018-05-19 21:43 ` Marcelo Ricardo Leitner
2018-05-20 6:22 ` Jiri Pirko
2018-05-20 10:59 ` Vlad Buslov
2018-05-14 14:27 ` [PATCH 07/14] net: sched: use reference counting action init Vlad Buslov
2018-05-15 11:24 ` Jiri Pirko
2018-05-15 11:32 ` Vlad Buslov
2018-05-15 11:39 ` Jiri Pirko
2018-05-15 11:41 ` Vlad Buslov
2018-05-15 11:57 ` Jiri Pirko
2018-05-15 12:00 ` Vlad Buslov
2018-05-14 14:27 ` [PATCH 08/14] net: sched: account for temporary action reference Vlad Buslov
2018-05-16 7:12 ` Jiri Pirko
2018-05-14 14:27 ` [PATCH 09/14] net: sched: don't release reference on action overwrite Vlad Buslov
2018-05-16 7:43 ` Jiri Pirko
2018-05-16 7:47 ` Vlad Buslov
2018-05-16 7:50 ` Jiri Pirko
2018-05-19 21:52 ` Marcelo Ricardo Leitner
2018-05-20 18:42 ` Vlad Buslov
2018-05-14 14:27 ` [PATCH 10/14] net: sched: extend act API for lockless actions Vlad Buslov
2018-05-16 7:50 ` Jiri Pirko
2018-05-16 8:16 ` Vlad Buslov
2018-05-16 8:56 ` Jiri Pirko
2018-05-16 9:39 ` Vlad Buslov
2018-05-19 22:17 ` Marcelo Ricardo Leitner
2018-05-14 14:27 ` [PATCH 11/14] net: core: add new/replace rate estimator lock parameter Vlad Buslov
2018-05-16 9:54 ` Jiri Pirko
2018-05-16 10:00 ` Vlad Buslov
2018-05-16 10:11 ` Jiri Pirko
2018-05-14 14:27 ` [PATCH 12/14] net: sched: retry action check-insert on concurrent modification Vlad Buslov
2018-05-16 9:59 ` Jiri Pirko
2018-05-16 11:55 ` Vlad Buslov
2018-05-16 12:26 ` Jiri Pirko
2018-05-16 12:43 ` Vlad Buslov
2018-05-16 13:21 ` Jiri Pirko
2018-05-16 13:52 ` Vlad Buslov
2018-05-16 14:13 ` Jiri Pirko
2018-05-16 14:26 ` Vlad Buslov
2018-05-16 14:55 ` Jiri Pirko
2018-05-19 22:35 ` Marcelo Ricardo Leitner
2018-05-14 14:27 ` [PATCH 13/14] net: sched: use unique idr insert function in unlocked actions Vlad Buslov
2018-05-16 9:50 ` Jiri Pirko
2018-05-16 9:54 ` Vlad Buslov
2018-05-19 22:20 ` Marcelo Ricardo Leitner
2018-05-20 21:13 ` Or Gerlitz
2018-05-20 21:33 ` Marcelo Ricardo Leitner
2018-05-20 21:40 ` Or Gerlitz
2018-05-20 22:43 ` Marcelo Ricardo Leitner
2018-05-14 14:27 ` [PATCH 14/14] net: sched: implement delete for all actions Vlad Buslov
2018-05-16 9:48 ` Jiri Pirko
2018-05-16 9:58 ` Vlad Buslov
2018-05-19 22:45 ` Marcelo Ricardo Leitner
2018-05-14 18:03 ` [PATCH 00/14] Modify action API for implementing lockless actions Jamal Hadi Salim
2018-05-14 20:46 ` Vlad Buslov
2018-05-15 18:25 ` Jamal Hadi Salim
2018-05-15 21:21 ` Vlad Buslov
2018-05-15 8:20 ` Jiri Pirko
2018-05-24 23:34 ` Cong Wang
2018-05-25 20:39 ` Vlad Buslov
2018-05-25 21:40 ` Cong Wang
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