Message-ID: <6e2ae46c-5407-ca6a-3353-69e76f10d913@linux.ibm.com>
Date:   Wed, 5 Jan 2022 14:25:43 +0100
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Subject: Re: [PATCH net v3] net/smc: Reset conn->lgr when link group
 registration fails
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To:     Wen Gu <guwen@linux.alibaba.com>, dust.li@linux.alibaba.com,
        davem@davemloft.net, kuba@kernel.org
Cc:     linux-s390@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <1641364133-61284-1-git-send-email-guwen@linux.alibaba.com>
 <20220105075408.GC31579@linux.alibaba.com>
 <23b607fe-95da-ea8a-8dda-900a51572b90@linux.alibaba.com>
From:   Karsten Graul <kgraul@linux.ibm.com>
Organization: IBM Deutschland Research & Development GmbH
In-Reply-To: <23b607fe-95da-ea8a-8dda-900a51572b90@linux.alibaba.com>
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On 05/01/2022 09:55, Wen Gu wrote:
> On 2022/1/5 3:54 pm, dust.li wrote:
> 
>>> -        if (rc)
>>> +        if (rc) {
>>> +            spin_lock_bh(lgr_lock);
>>> +            if (!list_empty(&lgr->list))
>>> +                list_del_init(&lgr->list);
>>> +            spin_unlock_bh(lgr_lock);
>>> +            __smc_lgr_terminate(lgr, true);
>>
>> What about adding a smc_lgr_terminate() wrapper and put list_del_init()
>> and __smc_lgr_terminate() into it ?
> 
> Adding a new wrapper is a good idea. But I think the logic here is relatively simple.
> So instead of wrapping them, I coded them like what smc_lgr_cleanup_early() does.

It might look cleaner with the following changes:
- adopt smc_lgr_cleanup_early() to take only an lgr as parameter and remove the call to smc_conn_free()
- change smc_conn_abort() (which is the only caller of smc_lgr_cleanup_early() right now), always
  call smc_conn_free() and if (local_first) additionally call smc_lgr_cleanup_early() 
  (hold a local copy of the lgr for this call)
- finally call smc_lgr_cleanup_early(lgr) from smc_conn_create()

This should be the same processing, but the smc_conn_free() is moved to smc_conn_abort() where
it looks to be a better place for this call. And smc_lgr_cleanup_early() takes only care of an lgr.

What do you think? Did I miss something?