From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <igt-dev-bounces@lists.freedesktop.org>
Message-ID: <3d3c7982-5ad3-d5a7-0574-ec1b9848dd2a@linux.intel.com>
Date: Mon, 23 Jan 2023 10:24:07 +0000
MIME-Version: 1.0
Content-Language: en-US
To: "Das, Nirmoy" <nirmoy.das@linux.intel.com>,
 igt-dev@lists.freedesktop.org, Intel-gfx@lists.freedesktop.org
References: <20230119155428.3260937-1-tvrtko.ursulin@linux.intel.com>
 <46f7db49-eb5c-515f-b450-75cac53d770e@linux.intel.com>
From: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
In-Reply-To: <46f7db49-eb5c-515f-b450-75cac53d770e@linux.intel.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit
Subject: Re: [igt-dev] [Intel-gfx] [PATCH i-g-t] intel_gpu_top: Fix cleanup
 on old kernels / unsupported GPU
List-Unsubscribe: <https://lists.freedesktop.org/mailman/options/igt-dev>,
 <mailto:igt-dev-request@lists.freedesktop.org?subject=unsubscribe>
List-Archive: <https://lists.freedesktop.org/archives/igt-dev>
List-Post: <mailto:igt-dev@lists.freedesktop.org>
List-Help: <mailto:igt-dev-request@lists.freedesktop.org?subject=help>
List-Subscribe: <https://lists.freedesktop.org/mailman/listinfo/igt-dev>,
 <mailto:igt-dev-request@lists.freedesktop.org?subject=subscribe>
Errors-To: igt-dev-bounces@lists.freedesktop.org
Sender: "igt-dev" <igt-dev-bounces@lists.freedesktop.org>
List-ID: <igt-dev@lists.freedesktop.org>


On 20/01/2023 14:29, Das, Nirmoy wrote:
> Hi Tvrtko,
> 
> On 1/19/2023 4:54 PM, Tvrtko Ursulin wrote:
>> From: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
>>
>> Avoid trying to dereference null engines on exit when there are either
>> none which are supported, or kernel does not have i915 PMU support.
>>
>> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
>> ---
>>   tools/intel_gpu_top.c | 10 +++++++---
>>   1 file changed, 7 insertions(+), 3 deletions(-)
>>
>> diff --git a/tools/intel_gpu_top.c b/tools/intel_gpu_top.c
>> index 7aa233570463..517dc2995d26 100644
>> --- a/tools/intel_gpu_top.c
>> +++ b/tools/intel_gpu_top.c
>> @@ -448,6 +448,9 @@ static void free_engines(struct engines *engines)
>>       };
>>       unsigned int i;
>> +    if (!engines)
>> +        return;
>> +
> 
> 
> This check should happen before the  struct pmu_counter free_list 
> generation.

I could, but it doesn't have to, not sure what reasons for should you 
have in mind?

Regards,

Tvrtko

> 
> Regards,
> 
> Nirmoy
> 
>>       for (pmu = &free_list[0]; *pmu; pmu++) {
>>           if ((*pmu)->present)
>>               free((char *)(*pmu)->units);
>> @@ -2568,7 +2571,7 @@ int main(int argc, char **argv)
>>               "Failed to detect engines! (%s)\n(Kernel 4.16 or newer 
>> is required for i915 PMU support.)\n",
>>               strerror(errno));
>>           ret = EXIT_FAILURE;
>> -        goto err;
>> +        goto err_engines;
>>       }
>>       ret = pmu_init(engines);
>> @@ -2585,7 +2588,7 @@ int main(int argc, char **argv)
>>   "More information can be found at 'Perf events and tool security' 
>> document:\n"
>>   
>> "https://www.kernel.org/doc/html/latest/admin-guide/perf-security.html\n");
>>           ret = EXIT_FAILURE;
>> -        goto err;
>> +        goto err_pmu;
>>       }
>>       ret = EXIT_SUCCESS;
>> @@ -2699,8 +2702,9 @@ int main(int argc, char **argv)
>>           free_clients(clients);
>>       free(codename);
>> -err:
>> +err_pmu:
>>       free_engines(engines);
>> +err_engines:
>>       free(pmu_device);
>>   exit:
>>       igt_devices_free();