From: "Medvedkin, Vladimir" <vladimir.medvedkin@intel.com>
To: Kevin Traynor <ktraynor@redhat.com>, <dev@dpdk.org>
Subject: Re: [PATCH] app/test-fib: fix possible division by zero
Date: Wed, 12 Jan 2022 16:49:11 +0100 [thread overview]
Message-ID: <7dbf048e-27c0-6143-5b25-9644b87fc8c0@intel.com> (raw)
In-Reply-To: <f06c8d6d-c0d6-5dbc-e325-627fbcb11f2e@redhat.com>
Hi Kevin,
On 11/01/2022 17:15, Kevin Traynor wrote:
> On 23/12/2021 15:25, Vladimir Medvedkin wrote:
>> This patch fixes the division by 0, which occurs if the number of
>> routes is less than 10.
>> Can be triggered by passing -n argument with value < 10:
>>
>
> 9 causing a divide by zero - another example of inflation :-)
>
Too bad that we are not working in a wheel
(https://en.wikipedia.org/wiki/Wheel_theory), where division by 0 is
always defined :)
>> ./dpdk-test-fib -- -n 9
>> ...
>> Floating point exception (core dumped)
>>
>> Fixes: 103809d032cd ("app/test-fib: add test application for FIB")
>> Cc: vladimir.medvedkin@intel.com
>>
>
> You probably want to add 'Cc: stable@dpdk.org' for this.
>
>> Signed-off-by: Vladimir Medvedkin <vladimir.medvedkin@intel.com>
>> ---
>> app/test-fib/main.c | 40 ++++++++++++++++++++++++----------------
>> 1 file changed, 24 insertions(+), 16 deletions(-)
>>
>> diff --git a/app/test-fib/main.c b/app/test-fib/main.c
>> index ecd420116a..9bc8b8a7ca 100644
>> --- a/app/test-fib/main.c
>> +++ b/app/test-fib/main.c
>> @@ -902,8 +902,9 @@ run_v4(void)
>> return -ret;
>> }
>> }
>> - printf("AVG FIB add %"PRIu64"\n",
>> - (rte_rdtsc_precise() - start) / j);
>> + if (j != 0)
>> + printf("AVG FIB add %"PRIu64"\n",
>> + (rte_rdtsc_precise() - start) / j);
>
>
> You are just not printing the result for these cases. Do you think it is
> worth to print a warning message (one), and update any documentation so
> the user is aware of the acceptable bounds?
>
Agree, I'll send v2
>> i += j;
>> }
>> @@ -930,8 +931,9 @@ run_v4(void)
>> return -ret;
>> }
>> }
>> - printf("AVG LPM add %"PRIu64"\n",
>> - (rte_rdtsc_precise() - start) / j);
>> + if (j != 0)
>> + printf("AVG LPM add %"PRIu64"\n",
>> + (rte_rdtsc_precise() - start) / j);
>> i += j;
>> }
>> }
>> @@ -984,8 +986,9 @@ run_v4(void)
>> for (j = 0; j < (config.nb_routes - i) / k; j++)
>> rte_fib_delete(fib, rt[i + j].addr, rt[i + j].depth);
>> - printf("AVG FIB delete %"PRIu64"\n",
>> - (rte_rdtsc_precise() - start) / j);
>> + if (j != 0)
>> + printf("AVG FIB delete %"PRIu64"\n",
>> + (rte_rdtsc_precise() - start) / j);
>> i += j;
>> }
>> @@ -996,8 +999,9 @@ run_v4(void)
>> rte_lpm_delete(lpm, rt[i + j].addr,
>> rt[i + j].depth);
>> - printf("AVG LPM delete %"PRIu64"\n",
>> - (rte_rdtsc_precise() - start) / j);
>> + if (j != 0)
>> + printf("AVG LPM delete %"PRIu64"\n",
>> + (rte_rdtsc_precise() - start) / j);
>> i += j;
>> }
>> }
>> @@ -1097,8 +1101,9 @@ run_v6(void)
>> return -ret;
>> }
>> }
>> - printf("AVG FIB add %"PRIu64"\n",
>> - (rte_rdtsc_precise() - start) / j);
>> + if (j != 0)
>> + printf("AVG FIB add %"PRIu64"\n",
>> + (rte_rdtsc_precise() - start) / j);
>> i += j;
>> }
>> @@ -1125,8 +1130,9 @@ run_v6(void)
>> return -ret;
>> }
>> }
>> - printf("AVG LPM add %"PRIu64"\n",
>> - (rte_rdtsc_precise() - start) / j);
>> + if (j != 0)
>> + printf("AVG LPM add %"PRIu64"\n",
>> + (rte_rdtsc_precise() - start) / j);
>> i += j;
>> }
>> }
>> @@ -1183,8 +1189,9 @@ run_v6(void)
>> for (j = 0; j < (config.nb_routes - i) / k; j++)
>> rte_fib6_delete(fib, rt[i + j].addr, rt[i + j].depth);
>> - printf("AVG FIB delete %"PRIu64"\n",
>> - (rte_rdtsc_precise() - start) / j);
>> + if (j != 0)
>> + printf("AVG FIB delete %"PRIu64"\n",
>> + (rte_rdtsc_precise() - start) / j);
>> i += j;
>> }
>> @@ -1195,8 +1202,9 @@ run_v6(void)
>> rte_lpm6_delete(lpm, rt[i + j].addr,
>> rt[i + j].depth);
>> - printf("AVG LPM delete %"PRIu64"\n",
>> - (rte_rdtsc_precise() - start) / j);
>> + if (j != 0)
>> + printf("AVG LPM delete %"PRIu64"\n",
>> + (rte_rdtsc_precise() - start) / j);
>> i += j;
>> }
>> }
>>
>
--
Regards,
Vladimir
prev parent reply other threads:[~2022-01-12 15:49 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-12-23 15:25 Vladimir Medvedkin
2022-01-11 16:15 ` Kevin Traynor
2022-01-12 15:49 ` Medvedkin, Vladimir [this message]
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