Re: [Intel-gfx] [PATCH i-g-t 5/6] intel_gpu_top: Fix cleanup on old kernels / unsupported GPU

From: Kamil Konieczny <kamil.konieczny@linux.intel.com>
To: igt-dev@lists.freedesktop.org
Cc: intel-gfx@lists.freedesktop.org, Nirmoy Das <nirmoy.das@intel.com>
Subject: Re: [Intel-gfx] [PATCH i-g-t 5/6] intel_gpu_top: Fix cleanup on old kernels / unsupported GPU
Date: Fri, 27 Jan 2023 17:10:52 +0100	[thread overview]
Message-ID: <20230127161052.thz5q2sqxtge2cwn@kamilkon-desk1> (raw)
In-Reply-To: <20230127111241.3624629-6-tvrtko.ursulin@linux.intel.com>

Hi Tvrtko,

On 2023-01-27 at 11:12:40 +0000, 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.
> 
> Also fix a memory leak on the same failure path just so Valgrind runs are
> quite.
> 
> v2:
>  * Fix a memory leak in the same failure mode too.

Please rebase, patch do not apply.

> 
> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
> Acked-by: Nirmoy Das <nirmoy.das@intel.com> # v1
-------------------------------------------- ^^^^^
Delete this.

Rest looks good,

Regards,
Kamil

> ---
>  tools/intel_gpu_top.c | 21 ++++++++++++++-------
>  1 file changed, 14 insertions(+), 7 deletions(-)
> 
> diff --git a/tools/intel_gpu_top.c b/tools/intel_gpu_top.c
> index 7aa233570463..0a1de41b3374 100644
> --- a/tools/intel_gpu_top.c
> +++ b/tools/intel_gpu_top.c
> @@ -340,7 +340,7 @@ static struct engines *discover_engines(char *device)
>  
>  	d = opendir(sysfs_root);
>  	if (!d)
> -		return NULL;
> +		goto err;
>  
>  	while ((dent = readdir(d)) != NULL) {
>  		const char *endswith = "-busy";
> @@ -423,10 +423,8 @@ static struct engines *discover_engines(char *device)
>  	}
>  
>  	if (ret) {
> -		free(engines);
>  		errno = ret;
> -
> -		return NULL;
> +		goto err;
>  	}
>  
>  	qsort(engine_ptr(engines, 0), engines->num_engines,
> @@ -435,6 +433,11 @@ static struct engines *discover_engines(char *device)
>  	engines->root = d;
>  
>  	return engines;
> +
> +err:
> +	free(engines);
> +
> +	return NULL;
>  }
>  
>  static void free_engines(struct engines *engines)
> @@ -448,6 +451,9 @@ static void free_engines(struct engines *engines)
>  	};
>  	unsigned int i;
>  
> +	if (!engines)
> +		return;
> +
>  	for (pmu = &free_list[0]; *pmu; pmu++) {
>  		if ((*pmu)->present)
>  			free((char *)(*pmu)->units);
> @@ -2568,7 +2574,7 @@ 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 +2591,7 @@ 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 +2705,9 @@ 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();
> -- 
> 2.34.1
> 