Re: rhashtable: Kill harmless RCU warning in rhashtable_walk_init

From	David Miller <davem@davemloft.net>
Newsgroups	linux.kernel
Subject	Re: rhashtable: Kill harmless RCU warning in rhashtable_walk_init
Date	2015-12-18 22:30 +0100
Message-ID	<qHaL8-2xT-1@gated-at.bofh.it> (permalink)
References	<qGWIa-1Xj-7@gated-at.bofh.it> <qH2NA-5M6-5@gated-at.bofh.it> <qH36X-682-19@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Fri, 18 Dec 2015 21:14:08 +0800

> On Fri, Dec 18, 2015 at 04:54:14AM -0800, Eric Dumazet wrote:
>>
>> You can avoid the comment by using the self documented and lockdep
>> enabled primitive
>> 
>> iter->walker->tbl = rcu_dereference_protected(ht->tbl,
>> 					      lockdep_is_held(&ht->lock));
> 
> That is just gross.  I think a comment is much better in this case.

Herbert, this macro was created exactly to handle this situation,
and this is what we do everywhere else in the tree.

Please use it.

Thanks.
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Re: [lkp] [rhashtable] f9f51b8070: INFO: suspicious RCU usage. ] Herbert Xu <herbert@gondor.apana.org.au> - 2015-12-18 06:40 +0100
  rhashtable: Kill harmless RCU warning in rhashtable_walk_init Herbert Xu <herbert@gondor.apana.org.au> - 2015-12-18 07:30 +0100
    Re: rhashtable: Kill harmless RCU warning in rhashtable_walk_init Eric Dumazet <eric.dumazet@gmail.com> - 2015-12-18 14:00 +0100
      Re: rhashtable: Kill harmless RCU warning in rhashtable_walk_init Herbert Xu <herbert@gondor.apana.org.au> - 2015-12-18 14:20 +0100
        Re: rhashtable: Kill harmless RCU warning in rhashtable_walk_init David Miller <davem@davemloft.net> - 2015-12-18 22:30 +0100
          [PATCH v2] rhashtable: Kill harmless RCU warning in  rhashtable_walk_init Herbert Xu <herbert@gondor.apana.org.au> - 2015-12-19 03:50 +0100
            Re: [LKP] [PATCH v2] rhashtable: Kill harmless RCU warning in  rhashtable_walk_init Fengguang Wu <fengguang.wu@intel.com> - 2015-12-19 05:50 +0100
            Re: [PATCH v2] rhashtable: Kill harmless RCU warning in  rhashtable_walk_init David Miller <davem@davemloft.net> - 2015-12-19 05:50 +0100

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