Re: [PATCH v6 04/21] x86/resctrl: Group struct rdt_hw_domain cleanup

[haoxin <xhao@linux.alibaba.com>]

在 2022/9/2 下午11:48, James Morse 写道:
> domain_add_cpu() and domain_remove_cpu() need to kfree() the child
> arrays that were allocated by domain_setup_ctrlval().
>
> As this memory is moved around, and new arrays are created, adjusting
> the error handling cleanup code becomes noisier.
>
> To simplify this, move all the kfree() calls into a domain_free() helper.
> This depends on struct rdt_hw_domain being kzalloc()d, allowing it to
> unconditionally kfree() all the child arrays.
>
> Reviewed-by: Jamie Iles <quic_jiles@quicinc.com>
> Tested-by: Xin Hao <xhao@linux.alibaba.com>
> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com>
> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com>
> Tested-by: Cristian Marussi <cristian.marussi@arm.com>
> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
> Signed-off-by: James Morse <james.morse@arm.com>
> ---
> Changes since v2:
>   * Made domain_free() static.
>
> Changes since v1:
>   * This patch is new
> ---
>   arch/x86/kernel/cpu/resctrl/core.c | 17 ++++++++++-------
>   1 file changed, 10 insertions(+), 7 deletions(-)
>
> diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
> index 25f30148478b..e37889f7a1a5 100644
> --- a/arch/x86/kernel/cpu/resctrl/core.c
> +++ b/arch/x86/kernel/cpu/resctrl/core.c
> @@ -414,6 +414,13 @@ void setup_default_ctrlval(struct rdt_resource *r, u32 *dc, u32 *dm)
>   	}
>   }
>   
> +static void domain_free(struct rdt_hw_domain *hw_dom)
add inline ?
> +{
> +	kfree(hw_dom->ctrl_val);
> +	kfree(hw_dom->mbps_val);
> +	kfree(hw_dom);
> +}
> +
>   static int domain_setup_ctrlval(struct rdt_resource *r, struct rdt_domain *d)
>   {
>   	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
> @@ -488,7 +495,7 @@ static void domain_add_cpu(int cpu, struct rdt_resource *r)
>   	rdt_domain_reconfigure_cdp(r);
>   
>   	if (r->alloc_capable && domain_setup_ctrlval(r, d)) {
> -		kfree(hw_dom);
> +		domain_free(hw_dom);
>   		return;
>   	}
>   
> @@ -497,9 +504,7 @@ static void domain_add_cpu(int cpu, struct rdt_resource *r)
>   	err = resctrl_online_domain(r, d);
>   	if (err) {
>   		list_del(&d->list);
> -		kfree(hw_dom->ctrl_val);
> -		kfree(hw_dom->mbps_val);
> -		kfree(hw_dom);
> +		domain_free(hw_dom);
>   	}
>   }
>   
> @@ -547,12 +552,10 @@ static void domain_remove_cpu(int cpu, struct rdt_resource *r)
>   		if (d->plr)
>   			d->plr->d = NULL;
>   
> -		kfree(hw_dom->ctrl_val);
> -		kfree(hw_dom->mbps_val);
>   		bitmap_free(d->rmid_busy_llc);
>   		kfree(d->mbm_total);
>   		kfree(d->mbm_local);
> -		kfree(hw_dom);
> +		domain_free(hw_dom);
>   		return;
>   	}
>