From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jan Blunck <jblunck@infradead.org>
Subject: Re: [PATCH] eal: bus scan and probe never fail
Date: Tue, 19 Sep 2017 20:51:33 +0200
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References: <20170812102220.27773-1-shreyansh.jain@nxp.com>
 <422ce0c6-7868-b601-2fe9-e361497d7b14@nxp.com>
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Cc: Shreyansh Jain <shreyansh.jain@nxp.com>, dev <dev@dpdk.org>,
 Thomas Monjalon <thomas@monjalon.net>
To: Hemant Agrawal <hemant.agrawal@nxp.com>
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On Mon, Sep 18, 2017 at 1:36 PM, Hemant Agrawal <hemant.agrawal@nxp.com> wrote:
> Tested-by: Hemant Agrawal <hemant.agrawal@nxp.com>
>
>
> On 8/12/2017 3:52 PM, Shreyansh Jain wrote:
>>
>> Bus scan is responsible for finding devices over *all* buses.
>> Some of these buses might not be able to scan but that should
>> not prevent other buses to be scanned.
>>

If scanning the bus fails this is signaling an error. In that case we
might even want to unregister the bus.

>> Same is the case for probing. It is possible that some devices which
>> were scanned didn't have a specific driver. That should not prevent
>> other buses from being probed.

Absolutely correct.

>>
>> Signed-off-by: Shreyansh Jain <shreyansh.jain@nxp.com>
>>
>> ---
>> Until now, this decision was left onto author of bus specific scan and
>> probe function. But, that is incorrect.
>> ---
>>  lib/librte_eal/common/eal_common_bus.c | 12 +++---------
>>  1 file changed, 3 insertions(+), 9 deletions(-)
>>
>> diff --git a/lib/librte_eal/common/eal_common_bus.c
>> b/lib/librte_eal/common/eal_common_bus.c
>> index 08bec2d..58e1084 100644
>> --- a/lib/librte_eal/common/eal_common_bus.c
>> +++ b/lib/librte_eal/common/eal_common_bus.c
>> @@ -73,11 +73,9 @@ rte_bus_scan(void)
>>
>>         TAILQ_FOREACH(bus, &rte_bus_list, next) {
>>                 ret = bus->scan();
>> -               if (ret) {
>> +               if (ret)
>>                         RTE_LOG(ERR, EAL, "Scan for (%s) bus failed.\n",
>>                                 bus->name);
>> -                       return ret;
>> -               }
>>         }
>>
>>         return 0;
>> @@ -97,20 +95,16 @@ rte_bus_probe(void)
>>                 }
>>
>>                 ret = bus->probe();
>> -               if (ret) {
>> +               if (ret)
>>                         RTE_LOG(ERR, EAL, "Bus (%s) probe failed.\n",
>>                                 bus->name);
>> -                       return ret;
>> -               }
>>         }
>>
>>         if (vbus) {
>>                 ret = vbus->probe();
>> -               if (ret) {
>> +               if (ret)
>>                         RTE_LOG(ERR, EAL, "Bus (%s) probe failed.\n",
>>                                 vbus->name);
>> -                       return ret;
>> -               }
>>         }
>>
>>         return 0;
>>
>