On Thu, Dec 14, 2017 at 3:10 AM, Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx> wrote: > Add a new sysfs subsystem, /sys/devices/system/hmat, which surfaces > information about memory initiators and memory targets to the user. These > initiators and targets are described by the ACPI SRAT and HMAT tables. > > A "memory initiator" in this case is a NUMA node containing one or more > devices such as CPU or separate memory I/O devices that can initiate > memory requests. A "memory target" is NUMA node containing at least one > CPU-accessible physical address range. > > The key piece of information surfaced by this patch is the mapping between > the ACPI table "proximity domain" numbers, held in the "firmware_id" > attribute, and Linux NUMA node numbers. Every ACPI proximity domain will > end up being a unique NUMA node in Linux, but the numbers may get reordered > and Linux can create extra NUMA nodes that don't map back to ACPI proximity > domains. The firmware_id value is needed if anyone ever wants to look at > the ACPI HMAT and SRAT tables directly and make sense of how they map to > NUMA nodes in Linux. > > Initiators are found at /sys/devices/system/hmat/mem_initX, and the > attributes for a given initiator look like this: > > # tree mem_init0 > mem_init0 > ├── firmware_id > ├── node0 -> ../../node/node0 > ├── power > │ ├── async > │ ... > ├── subsystem -> ../../../../bus/hmat > └── uevent > > Where "mem_init0" on my system represents the CPU acting as a memory > initiator at NUMA node 0. Users can discover which CPUs are part of this > memory initiator by following the node0 symlink and looking at cpumap, > cpulist and the cpu* symlinks. > > Targets are found at /sys/devices/system/hmat/mem_tgtX, and the attributes > for a given target look like this: > > # tree mem_tgt2 > mem_tgt2 > ├── firmware_id > ├── is_cached > ├── node2 -> ../../node/node2 > ├── power > │ ├── async > │ ... > ├── subsystem -> ../../../../bus/hmat > └── uevent > > Users can discover information about the memory owned by this memory target > by following the node2 symlink and looking at meminfo, vmstat and at the > memory* memory section symlinks. > > Signed-off-by: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx> > --- > MAINTAINERS | 6 + > drivers/acpi/Kconfig | 1 + > drivers/acpi/Makefile | 1 + > drivers/acpi/hmat/Kconfig | 7 + > drivers/acpi/hmat/Makefile | 2 + > drivers/acpi/hmat/core.c | 536 ++++++++++++++++++++++++++++++++++++++++++ > drivers/acpi/hmat/hmat.h | 47 ++++ > drivers/acpi/hmat/initiator.c | 43 ++++ > drivers/acpi/hmat/target.c | 55 +++++ > 9 files changed, 698 insertions(+) > create mode 100644 drivers/acpi/hmat/Kconfig > create mode 100644 drivers/acpi/hmat/Makefile > create mode 100644 drivers/acpi/hmat/core.c > create mode 100644 drivers/acpi/hmat/hmat.h > create mode 100644 drivers/acpi/hmat/initiator.c > create mode 100644 drivers/acpi/hmat/target.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 82ad0eabce4f..64ebec0708de 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -6366,6 +6366,12 @@ S: Supported > F: drivers/scsi/hisi_sas/ > F: Documentation/devicetree/bindings/scsi/hisilicon-sas.txt > > +HMAT - ACPI Heterogeneous Memory Attribute Table Support > +M: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx> > +L: linux-mm@xxxxxxxxx > +S: Supported > +F: drivers/acpi/hmat/ > + > HMM - Heterogeneous Memory Management > M: Jérôme Glisse <jglisse@xxxxxxxxxx> > L: linux-mm@xxxxxxxxx > diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig > index 46505396869e..21cdd1288430 100644 > --- a/drivers/acpi/Kconfig > +++ b/drivers/acpi/Kconfig > @@ -466,6 +466,7 @@ config ACPI_REDUCED_HARDWARE_ONLY > If you are unsure what to do, do not enable this option. > > source "drivers/acpi/nfit/Kconfig" > +source "drivers/acpi/hmat/Kconfig" > > source "drivers/acpi/apei/Kconfig" > source "drivers/acpi/dptf/Kconfig" > diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile > index 41954a601989..ed5eab6b0412 100644 > --- a/drivers/acpi/Makefile > +++ b/drivers/acpi/Makefile > @@ -75,6 +75,7 @@ obj-$(CONFIG_ACPI_PROCESSOR) += processor.o > obj-$(CONFIG_ACPI) += container.o > obj-$(CONFIG_ACPI_THERMAL) += thermal.o > obj-$(CONFIG_ACPI_NFIT) += nfit/ > +obj-$(CONFIG_ACPI_HMAT) += hmat/ > obj-$(CONFIG_ACPI) += acpi_memhotplug.o > obj-$(CONFIG_ACPI_HOTPLUG_IOAPIC) += ioapic.o > obj-$(CONFIG_ACPI_BATTERY) += battery.o > diff --git a/drivers/acpi/hmat/Kconfig b/drivers/acpi/hmat/Kconfig > new file mode 100644 > index 000000000000..954ad4701005 > --- /dev/null > +++ b/drivers/acpi/hmat/Kconfig > @@ -0,0 +1,7 @@ > +config ACPI_HMAT > + bool "ACPI Heterogeneous Memory Attribute Table Support" > + depends on ACPI_NUMA > + depends on SYSFS > + help > + Exports a sysfs representation of the ACPI Heterogeneous Memory > + Attributes Table (HMAT). > diff --git a/drivers/acpi/hmat/Makefile b/drivers/acpi/hmat/Makefile > new file mode 100644 > index 000000000000..edf4bcb1c97d > --- /dev/null > +++ b/drivers/acpi/hmat/Makefile > @@ -0,0 +1,2 @@ > +obj-$(CONFIG_ACPI_HMAT) := hmat.o > +hmat-y := core.o initiator.o target.o > diff --git a/drivers/acpi/hmat/core.c b/drivers/acpi/hmat/core.c > new file mode 100644 > index 000000000000..61b90dadf84b > --- /dev/null > +++ b/drivers/acpi/hmat/core.c > @@ -0,0 +1,536 @@ > +/* > + * Heterogeneous Memory Attributes Table (HMAT) representation in sysfs > + * > + * Copyright (c) 2017, Intel Corporation. > + * > + * This program is free software; you can redistribute it and/or modify it > + * under the terms and conditions of the GNU General Public License, > + * version 2, as published by the Free Software Foundation. > + * > + * This program is distributed in the hope it will be useful, but WITHOUT > + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for > + * more details. > + */ Minor nit for starters: you should use SPDX license indentifiers in new files and if you do so, the license boilerplace is not necessary any more. Thanks, Rafael -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href
