Re: [PATCH v1 1/7] iommu/arm-smmu-v3: Move ctx_desc out of s1_cfg

From: Jason Gunthorpe <jgg@nvidia.com>
To: Michael Shavit <mshavit@google.com>
Cc: Will Deacon <will@kernel.org>,
	Robin Murphy <robin.murphy@arm.com>,
	Joerg Roedel <joro@8bytes.org>,
	jean-philippe@linaro.org, nicolinc@nvidia.com,
	baolu.lu@linux.intel.com, linux-arm-kernel@lists.infradead.org,
	iommu@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v1 1/7] iommu/arm-smmu-v3: Move ctx_desc out of s1_cfg
Date: Thu, 27 Jul 2023 15:45:32 -0300	[thread overview]
Message-ID: <ZMK7TMA3BvInUx+l@nvidia.com> (raw)
In-Reply-To: <20230727182647.4106140-2-mshavit@google.com>

On Fri, Jul 28, 2023 at 02:26:17AM +0800, Michael Shavit wrote:
> @@ -715,25 +714,28 @@ enum arm_smmu_domain_stage {
>  };
>  
>  struct arm_smmu_domain {
> -	struct arm_smmu_device		*smmu;
> -	struct mutex			init_mutex; /* Protects smmu pointer */
> +	struct arm_smmu_device			*smmu;
> +	struct mutex				init_mutex; /* Protects smmu pointer */
>  
> -	struct io_pgtable_ops		*pgtbl_ops;
> -	bool				stall_enabled;
> -	atomic_t			nr_ats_masters;
> +	struct io_pgtable_ops			*pgtbl_ops;
> +	bool					stall_enabled;
> +	atomic_t				nr_ats_masters;
>  
> -	enum arm_smmu_domain_stage	stage;
> +	enum arm_smmu_domain_stage		stage;
>  	union {
> -		struct arm_smmu_s1_cfg	s1_cfg;
> -		struct arm_smmu_s2_cfg	s2_cfg;
> +		struct {
> +		struct arm_smmu_ctx_desc	cd;
> +		struct arm_smmu_s1_cfg		s1_cfg;
> +		};
> +		struct arm_smmu_s2_cfg		s2_cfg;
>  	};
>  
> -	struct iommu_domain		domain;
> +	struct iommu_domain			domain;
>  
> -	struct list_head		devices;
> -	spinlock_t			devices_lock;
> +	struct list_head			devices;
> +	spinlock_t				devices_lock;
>  
> -	struct list_head		mmu_notifiers;
> +	struct list_head			mmu_notifiers;
>  };

Don't re-indent a whole struct just to get column alignment. Do
a few lines around where you are touching.

This is also why I quite dislike column alignment, aside from being
unreadable, it harms readability of diffs and increases maintenance
costs.

Jason