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Reply-To: Gavin Shan <gshan@redhat.com>
Subject: Re: [PATCH v3 11/16] arch_topology: Check for non-negative value
 rather than -1 for IDs validity
To:     Sudeep Holla <sudeep.holla@arm.com>, linux-kernel@vger.kernel.org
Cc:     Atish Patra <atishp@atishpatra.org>,
        Atish Patra <atishp@rivosinc.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Morten Rasmussen <morten.rasmussen@arm.com>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Qing Wang <wangqing@vivo.com>,
        linux-arm-kernel@lists.infradead.org,
        linux-riscv@lists.infradead.org, Rob Herring <robh+dt@kernel.org>,
        Andy Shevchenko <andy.shevchenko@gmail.com>
References: <20220525081416.3306043-1-sudeep.holla@arm.com>
 <20220525081416.3306043-2-sudeep.holla@arm.com>
 <20220525081416.3306043-3-sudeep.holla@arm.com>
 <20220525081416.3306043-4-sudeep.holla@arm.com>
 <20220525081416.3306043-5-sudeep.holla@arm.com>
 <20220525081416.3306043-6-sudeep.holla@arm.com>
 <20220525081416.3306043-7-sudeep.holla@arm.com>
 <20220525081416.3306043-8-sudeep.holla@arm.com>
 <20220525081416.3306043-9-sudeep.holla@arm.com>
 <20220525081416.3306043-10-sudeep.holla@arm.com>
 <20220525081416.3306043-11-sudeep.holla@arm.com>
 <20220525081416.3306043-12-sudeep.holla@arm.com>
From:   Gavin Shan <gshan@redhat.com>
Message-ID: <59764f2b-60c8-3f0c-8159-3103f606494c@redhat.com>
Date:   Wed, 1 Jun 2022 11:38:33 +0800
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On 5/25/22 4:14 PM, Sudeep Holla wrote:
> Instead of just comparing the cpu topology IDs with -1 to check their
> validity, improve that by checking for a valid non-negative value.
> 
> Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
> ---
>   drivers/base/arch_topology.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 

Reviewed-by: Gavin Shan <gshan@redhat.com>

> diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c
> index 59dc2c80c439..f73a5e669e42 100644
> --- a/drivers/base/arch_topology.c
> +++ b/drivers/base/arch_topology.c
> @@ -637,7 +637,7 @@ static int __init parse_dt_topology(void)
>   	 * only mark cores described in the DT as possible.
>   	 */
>   	for_each_possible_cpu(cpu)
> -		if (cpu_topology[cpu].package_id == -1)
> +		if (cpu_topology[cpu].package_id < 0)
>   			ret = -EINVAL;
>   
>   out_map:
> @@ -709,7 +709,7 @@ void update_siblings_masks(unsigned int cpuid)
>   		if (cpuid_topo->cluster_id != cpu_topo->cluster_id)
>   			continue;
>   
> -		if (cpuid_topo->cluster_id != -1) {
> +		if (cpuid_topo->cluster_id >= 0) {
>   			cpumask_set_cpu(cpu, &cpuid_topo->cluster_sibling);
>   			cpumask_set_cpu(cpuid, &cpu_topo->cluster_sibling);
>   		}
>