[dpdk-dev] [PATCH v7 1/1] fbarray: fix duplicated fbarray file in secondary

[Yasufumi Ogawa]

On 2019/11/14 2:01, Burakov, Anatoly wrote:
> On 13-Nov-19 9:43 PM, yasufum.o at gmail.com wrote:
>> From: Yasufumi Ogawa <ogawa.yasufumi at lab.ntt.co.jp>
>>
>> In secondary_msl_create_walk(), it creates a file for fbarrays with its
>> PID for reserving unique name among secondary processes. However, it
>> does not work if several secondaries run as app containers because each
>> of containerized secondary has PID 1, and failed to reserve unique name
>> other than first one. To reserve unique name in each of containers, use
>> hostname in addition to PID.
>>
>> Cc: stable at dpdk.org
>>
>> Signed-off-by: Yasufumi Ogawa <yasufum.o at gmail.com>
>> ---
>>   lib/librte_eal/linux/eal/eal_memalloc.c | 16 +++++++++++++---
>>   1 file changed, 13 insertions(+), 3 deletions(-)
>>
>> diff --git a/lib/librte_eal/linux/eal/eal_memalloc.c 
>> b/lib/librte_eal/linux/eal/eal_memalloc.c
>> index af6d0d023..11de6d4d6 100644
>> --- a/lib/librte_eal/linux/eal/eal_memalloc.c
>> +++ b/lib/librte_eal/linux/eal/eal_memalloc.c
>> @@ -1365,6 +1365,12 @@ secondary_msl_create_walk(const struct 
>> rte_memseg_list *msl,
>>       struct rte_memseg_list *primary_msl, *local_msl;
>>       char name[PATH_MAX];
>>       int msl_idx, ret;
>> +    char hostname[HOST_NAME_MAX+1] = { 0 };
>> +    /* filename of secondary's fbarray is defined such as
>> +     * "fbarray_memseg-1048576k-0-0_PID_HOSTNAME" and length of PID
>> +     * can be 7 digits maximumly.
>> +     */
>> +    int fbarray_sec_name_len = 32 + 7 + 1 + HOST_NAME_MAX + 1;
> 
> What does 32 stand for? Maybe #define both 32 and 7 values?
Hi Anatoly,

Thank you for your comments! If my understanding is correct, the prefix 
"fbarray_memseg-1048576k-0-0_" is 28 digits and it could be larger if 
using the size of hugepage or the number of NUMA nodes are larger 
possibly. However, I think 32 digits is still enough.

 > Maybe #define both 32 and 7 values?
Yes. I think it should be better to use #define if this values are 
referred several times.

Thanks,
Yasufumi

> 
> Other than that,
> 
> Acked-by: Anatoly Burakov <anatoly.burakov at intel.com>
>