[PATCH] iommu/arm-smmu-v3: Stop pre-zeroing batch commands

Will Deacon will at kernel.org
Fri Aug 13 07:33:47 PDT 2021


On Wed, 11 Aug 2021 23:49:26 +0800, John Garry wrote:
> Pre-zeroing the batched commands structure is inefficient, as individual
> commands are zeroed later in arm_smmu_cmdq_build_cmd(). The size is quite
> large and commonly most commands won't even be used:
> 
> 	struct arm_smmu_cmdq_batch cmds = {};
> 345c:	52800001 	mov	w1, #0x0                   	// #0
> 3460:	d2808102 	mov	x2, #0x408                 	// #1032
> 3464:	910143a0 	add	x0, x29, #0x50
> 3468:	94000000 	bl	0 <memset>
> 
> [...]

Applied to will (for-joerg/arm-smmu/updates), thanks!

[1/1] iommu/arm-smmu-v3: Stop pre-zeroing batch commands
      https://git.kernel.org/will/c/fac956710ab0

Cheers,
-- 
Will

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