Re: [PATCH v7 7/7] perf/amd/iommu: Enable support for multiple IOMMUs

From: Suravee Suthikulpanit
Date: Fri Jan 13 2017 - 22:02:30 EST




On 1/13/17 18:49, Borislav Petkov wrote:
On Fri, Jan 13, 2017 at 05:24:01PM +0700, Suravee Suthikulpanit wrote:
IIUC, Perf tools looks at the /sys/devices/xxxxx to identify
availalble PMUs. Are you planning to have perf tools look at
/sys/devices/system/iommu/xxx instead?

No, I'm planning to understand what do you mean exactly. Because the
PMUs are, as I'm being pointed to, here:

#define EVENT_SOURCE_DEVICE_PATH "/bus/event_source/devices/"

Do you mean that, per chance?


Ah, okay. I can see the following directory path:

# ls -l /sys/devices/
drwxr-xr-x 5 root root 0 Jan 13 20:36 amd_iommu_0

# ls -l /sys/bus/event_source/devices/
lrwxrwxrwx 1 root root 0 Jan 13 20:33 amd_iommu_0 -> ../../../devices/amd_iommu_0

I'll update the commit log to mention /bus/event_source/devices/amd_iommu_X instead.

Thanks,
S