Re: [PATCH v6 02/13] PCI/P2PDMA: Add sysfs group to display p2pmem stats
From: Bjorn Helgaas <helgaas@kernel.org>
Date: 2018-09-21 13:07:09
Also in:
linux-nvme, linux-pci, linux-rdma, lkml, nvdimm
On Wed, Sep 12, 2018 at 06:11:45PM -0600, Logan Gunthorpe wrote:
Add a sysfs group to display statistics about P2P memory that is registered in each PCI device. Attributes in the group display the total amount of P2P memory, the amount available and whether it is published or not. Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
quoted hunk ↗ jump to hunk
+What: /sys/bus/pci/devices/.../p2pmem/available +Date: November 2017 +Contact: Logan Gunthorpe <logang@deltatee.com> +Description: + If the device has any Peer-to-Peer memory registered, this + file contains the amount of memory that has not been + allocated (in decimal). + +What: /sys/bus/pci/devices/.../p2pmem/size +Date: November 2017 +Contact: Logan Gunthorpe <logang@deltatee.com> +Description: + If the device has any Peer-to-Peer memory registered, this + file contains the total amount of memory that the device + provides (in decimal).
Maybe reorder this so the "size" (total amount) is documented before "available" (some subset of "size")?
quoted hunk ↗ jump to hunk
+ +What: /sys/bus/pci/devices/.../p2pmem/published +Date: November 2017 +Contact: Logan Gunthorpe <logang@deltatee.com> +Description: + If the device has any Peer-to-Peer memory registered, this + file contains a '1' if the memory has been published for + use inside the kernel or a '0' if it is only intended + for use within the driver that published it.
It doesn't read quite right to talk about "use within the driver that *published* it". Is it really published in that case? That sounds more like "private". I expected something like the following (but I don't claim to understand the whole use model here): ... this file contains a '1' if the memory has been published for use outside the driver that owns the device.