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Subject: Re: [PATCH 2/3] rhashtable-test: retry insert operations in threads
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Herbert Xu <herbert@gondor.apana.org.au>
Cc: tgraf@suug.ch, davem@davemloft.net, netdev@vger.kernel.org,
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Date: Tue, 01 Sep 2015 06:40:48 -0700
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On Tue, 2015-09-01 at 21:00 +0800, Herbert Xu wrote:
> On Tue, Sep 01, 2015 at 02:46:48PM +0200, Phil Sutter wrote:
> >
> > This is not an inherent behaviour of the implementation but general
> > agreement. The insertion may fail non-permanently (returning -EBUSY),
> > users are expected to handle this by retrying the operation.
> 
> Absolutely not.  The only reason for an insertion to fail is if we
> can't allocate enough memory.  Unless the user is also looping its
> kmalloc calls it definitely shouldn't be retrying the insert.
> 
> If an expansion fails it means either that the system is suffering
> a catastrophic memory shortage, or the user of rhashtable is doing
> something wrong.


-EBUSY does not sound as a memory allocation error.