Jonathan Cameron wrote: > On Mon, 07 Oct 2024 18:16:28 -0500 > ira.weiny@xxxxxxxxx wrote: > > > From: Navneet Singh <navneet.singh@xxxxxxxxx> > > > > Extent information can be helpful to the user to coordinate memory usage > > with the external orchestrator and FM. > > > > Expose the details of region extents by creating the following > > sysfs entries. > > > > /sys/bus/cxl/devices/dax_regionX/extentX.Y > > /sys/bus/cxl/devices/dax_regionX/extentX.Y/offset > > /sys/bus/cxl/devices/dax_regionX/extentX.Y/length > > /sys/bus/cxl/devices/dax_regionX/extentX.Y/tag > > > > Signed-off-by: Navneet Singh <navneet.singh@xxxxxxxxx> > > Co-developed-by: Ira Weiny <ira.weiny@xxxxxxxxx> > > Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx> > > > Trivial comments inline. > > Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> Thanks! > > > --- > > Changes: > > [djiang: Split sysfs docs up] > > [iweiny: Adjust sysfs docs dates] > > --- > > Documentation/ABI/testing/sysfs-bus-cxl | 32 ++++++++++++++++++ > > drivers/cxl/core/extent.c | 58 +++++++++++++++++++++++++++++++++ > > 2 files changed, 90 insertions(+) > > > > diff --git a/Documentation/ABI/testing/sysfs-bus-cxl b/Documentation/ABI/testing/sysfs-bus-cxl > > index b63ab622515f..64918180a3c9 100644 > > --- a/Documentation/ABI/testing/sysfs-bus-cxl > > +++ b/Documentation/ABI/testing/sysfs-bus-cxl > > @@ -632,3 +632,35 @@ Description: > > See Documentation/ABI/stable/sysfs-devices-node. access0 provides > > the number to the closest initiator and access1 provides the > > number to the closest CPU. > > + > > +What: /sys/bus/cxl/devices/dax_regionX/extentX.Y/offset > > +Date: December, 2024 > > +KernelVersion: v6.13 > > +Contact: linux-cxl@xxxxxxxxxxxxxxx > > +Description: > > + (RO) [For Dynamic Capacity regions only] Users can use the > > + extent information to create DAX devices on specific extents. > > + This is done by creating and destroying DAX devices in specific > > + sequences and looking at the mappings created. > > Similar to earlier patch, maybe put this doc for the directory, then > have much less duplication? > But none of the other directories are done this way so I'm inclined to keep it. > > > Extent offset > > + within the region. > > + > > +What: /sys/bus/cxl/devices/dax_regionX/extentX.Y/length > > +Date: December, 2024 > > +KernelVersion: v6.13 > > +Contact: linux-cxl@xxxxxxxxxxxxxxx > > +Description: > > + (RO) [For Dynamic Capacity regions only] Users can use the > > + extent information to create DAX devices on specific extents. > > + This is done by creating and destroying DAX devices in specific > > + sequences and looking at the mappings created. Extent length > > + within the region. > > + > > +What: /sys/bus/cxl/devices/dax_regionX/extentX.Y/tag > > +Date: December, 2024 > > +KernelVersion: v6.13 > > +Contact: linux-cxl@xxxxxxxxxxxxxxx > > +Description: > > + (RO) [For Dynamic Capacity regions only] Users can use the > > + extent information to create DAX devices on specific extents. > > + This is done by creating and destroying DAX devices in specific > > + sequences and looking at the mappings created. Extent tag. > > Maybe say we are treating it as a UUID? ok... How about? <quote> ... looking at the mappings created. UUID extent tag. </quote> > > diff --git a/drivers/cxl/core/extent.c b/drivers/cxl/core/extent.c > > index 69a7614ba6a9..a1eb6e8e4f1a 100644 > > --- a/drivers/cxl/core/extent.c > > +++ b/drivers/cxl/core/extent.c > > @@ -6,6 +6,63 @@ > > > +static struct attribute *region_extent_attrs[] = { > > + &dev_attr_offset.attr, > > + &dev_attr_length.attr, > > + &dev_attr_tag.attr, > > + NULL, > No need for trailing comma (one of my 'favourite' review comments :) I'm noticing... :-D Ira