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Subject: Re: [PATCH] RDMA/core: reduce IB_POLL_BATCH constant
To:     Max Gurtovoy <maxg@mellanox.com>,
        Chuck Lever <chuck.lever@oracle.com>,
        Bart Van Assche <Bart.VanAssche@wdc.com>
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        "leonro@mellanox.com" <leonro@mellanox.com>,
        "linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>
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From:   Sagi Grimberg <sagi@grimberg.me>
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Date:   Thu, 22 Feb 2018 17:39:09 +0200
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>> The only reason why I added this array on-stack was to allow consumers
>> that did not use ib_alloc_cq api to call it, but that seems like a
>> wrong decision when thinking it over again (as probably these users
>> did not set the wr_cqe correctly).
>>
>> How about we make ib_process_cq_direct use the cq wc array and add
>> a WARN_ON statement (and fail it gracefully) if the caller used this
>> API without calling ib_alloc_cq?
> 
> but we tried to avoid cuncurrent access to cq->wc.

Not sure its a valid use-case. But if there is a compelling
reason to keep it as is, then we can do smaller on-stack
array.