Re: [igt-dev] [Intel-gfx] [PATCH i-g-t] intel_gpu_top: Fix cleanup on old kernels / unsupported GPU

Das, Nirmoy
2023-01-20T14:29:43Z

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.

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();