Re: [dpdk-dev] [PATCH] rte_mempool_dump() crashes with NULL rte_mempool pointer.

["Wiles, Roger Keith" <keith.wiles@windriver.com>]

On Sep 27, 2014, at 8:55 PM, Neil Horman <nhorman@tuxdriver.com> wrote:

> On Sun, Sep 28, 2014 at 01:14:05AM +0000, Wiles, Roger Keith wrote:
>> 
>> On Sep 27, 2014, at 7:37 PM, Neil Horman <nhorman@tuxdriver.com> wrote:
>> 
>>> On Sat, Sep 27, 2014 at 06:35:01PM +0000, Wiles, Roger Keith wrote:
>>>> 
>>>> Check the FILE *f and rte_mempool *mp pointers for NULL and
>>>> return plus print out a message if RTE_LIBRTE_MEMPOOL_DEBUG is enabled.
>>>> 
>>>> Signed-off-by: Keith Wiles <keith.wiles@windriver.com>
>>>> ---
>>>> lib/librte_mempool/rte_mempool.c | 6 ++++++
>>>> 1 file changed, 6 insertions(+)
>>>> 
>>>> diff --git a/lib/librte_mempool/rte_mempool.c b/lib/librte_mempool/rte_mempool.c
>>>> index 332f469..efa6a6c 100644
>>>> --- a/lib/librte_mempool/rte_mempool.c
>>>> +++ b/lib/librte_mempool/rte_mempool.c
>>>> @@ -765,6 +765,12 @@ rte_mempool_dump(FILE *f, const struct rte_mempool *mp)
>>>>   unsigned common_count;
>>>>   unsigned cache_count;
>>>> 
>>>> +   if ( (f == NULL) || (mp == NULL) ) {
>>>> +#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
>>>> +       fprintf(stderr, "*** Called rte_mempool_dump(%p, %p) with NULL argument\n", f, mp);
>>>> +#endif /* RTE_LIBRTE_MEMPOOL_DEBUG */
>>>> +       return;
>>>> +   }
>>>>   fprintf(f, "mempool <%s>@%p\n", mp->name, mp);
>>>>   fprintf(f, "  flags=%x\n", mp->flags);
>>>>   fprintf(f, "  ring=<%s>@%p\n", mp->ring->name, mp->ring);
>>>> -- 
>>>> 2.1.0
>>>> 
>>>> 
>>> Maybe use RTE_VERIFY instead?
>>> Neil
>>> 
>> I did not think it needs to panic as it is just a debug function and returning would be fine by me, comments?
>> Do we have a similar RTE_VERIFY like function that does not panic?
>> 
> If we don't, it would seem useful to make one.  It beats having to do specific
> condition checking/error reporting.  RTE_VERIFY_WARN or some such.
> Neil

I decided to just use RTE_VERIFY() instead of creating a new macro for now, it seems this maybe an isolated case. I agree having RTE_VERIFY_WARN() would be nice, but as I was writing the macro I wanted to return from the function. For this routine ‘return’ would work as it returns (void), but for other routines a value may need to be returned.

Need a clean way to exit the routine without causing the macro to understand its return values. Just seem to become a bit messy at this point. Multiple macros for different return types or make the macros return a boolean value to be tested seemed to more complex then needed.
> 
>> Keith Wiles, Principal Technologist with CTO office, Wind River mobile 972-213-5533

Keith Wiles, Principal Technologist with CTO office, Wind River mobile 972-213-5533