Re: [PATCH v3 2/2] iommu/amd: Add basic debugfs infrastructure for AMD IOMMU

From: Hook, Gary
Date: Tue Apr 17 2018 - 13:43:06 EST

On 4/16/2018 8:52 PM, Mehta, Sohil wrote:
On Fri, 2018-04-06 at 08:17 -0500, Gary R Hook wrote:

diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
index 5eb1121d54b9..0ca250f626d9 100644
--- a/drivers/iommu/Makefile
+++ b/drivers/iommu/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_IOMMU_IOVA) += iova.o
Âobj-$(CONFIG_OF_IOMMU)Â+= of_iommu.o
Âobj-$(CONFIG_MSM_IOMMU) += msm_iommu.o
Âobj-$(CONFIG_AMD_IOMMU) += amd_iommu.o amd_iommu_init.o
+obj-$(CONFIG_IOMMU_DEBUG) += amd_iommu_debugfs.o

Compiling amd_iommu_debugfs.c seems to depend only
onÂCONFIG_IOMMU_DEBUG. Can we prevent the code within
amd_iommu_debugfs.c from getting compiled when either CONFIG_AMD_IOMMU
or CONFIG_IOMMU_DEBUG is disabled?

That's a good point. My intention was that only one switch was required to incorporate any DebugFS support, but I see now that I didn't consider all of the cases.

It appears that a per-device switch is also necessary. Unless someone has a better idea.

Âobj-$(CONFIG_AMD_IOMMU_V2) += amd_iommu_v2.o
Âobj-$(CONFIG_ARM_SMMU) += arm-smmu.o
Âobj-$(CONFIG_ARM_SMMU_V3) += arm-smmu-v3.o