Re: [RFC PATCH v2 02/20] tracing/filters: Enable filtering a cpumask field by another cpumask

From: Josh Poimboeuf <jpoimboe@kernel.org>
To: Valentin Schneider <vschneid@redhat.com>
Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org,
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	"Yair Podemsky" <ypodemsk@redhat.com>
Subject: Re: [RFC PATCH v2 02/20] tracing/filters: Enable filtering a cpumask field by another cpumask
Date: Wed, 26 Jul 2023 12:41:48 -0700	[thread overview]
Message-ID: <20230726194148.4jhyqqbtn3qqqqsq@treble> (raw)
In-Reply-To: <20230720163056.2564824-3-vschneid@redhat.com>

On Thu, Jul 20, 2023 at 05:30:38PM +0100, Valentin Schneider wrote:
>  int filter_assign_type(const char *type)
>  {
> -	if (strstr(type, "__data_loc") && strstr(type, "char"))
> -		return FILTER_DYN_STRING;
> +	if (strstr(type, "__data_loc")) {
> +		if (strstr(type, "char"))
> +			return FILTER_DYN_STRING;
> +		if (strstr(type, "cpumask_t"))
> +			return FILTER_CPUMASK;
> +		}

The closing bracket has the wrong indentation.

> +		/* Copy the cpulist between { and } */
> +		tmp = kmalloc((i - maskstart) + 1, GFP_KERNEL);
> +		strscpy(tmp, str + maskstart, (i - maskstart) + 1);

Need to check kmalloc() failure?  And also free tmp?

> +
> +		pred->mask = kzalloc(cpumask_size(), GFP_KERNEL);
> +		if (!pred->mask)
> +			goto err_mem;
> +
> +		/* Now parse it */
> +		if (cpulist_parse(tmp, pred->mask)) {
> +			parse_error(pe, FILT_ERR_INVALID_CPULIST, pos + i);
> +			goto err_free;
> +		}
> +
> +		/* Move along */
> +		i++;
> +		if (field->filter_type == FILTER_CPUMASK)
> +			pred->fn_num = FILTER_PRED_FN_CPUMASK;
> +

-- 
Josh