diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-cxl | 48 | ||||
| -rw-r--r-- | Documentation/admin-guide/perf/cxl.rst | 68 | ||||
| -rw-r--r-- | Documentation/admin-guide/perf/index.rst | 1 |
3 files changed, 117 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-cxl b/Documentation/ABI/testing/sysfs-bus-cxl index 48ac0d911801..6350dd82b9a9 100644 --- a/Documentation/ABI/testing/sysfs-bus-cxl +++ b/Documentation/ABI/testing/sysfs-bus-cxl @@ -58,6 +58,54 @@ Description: affinity for this device. +What: /sys/bus/cxl/devices/memX/security/state +Date: June, 2023 +KernelVersion: v6.5 +Contact: linux-cxl@vger.kernel.org +Description: + (RO) Reading this file will display the CXL security state for + that device. Such states can be: 'disabled', 'sanitize', when + a sanitization is currently underway; or those available only + for persistent memory: 'locked', 'unlocked' or 'frozen'. This + sysfs entry is select/poll capable from userspace to notify + upon completion of a sanitize operation. + + +What: /sys/bus/cxl/devices/memX/security/sanitize +Date: June, 2023 +KernelVersion: v6.5 +Contact: linux-cxl@vger.kernel.org +Description: + (WO) Write a boolean 'true' string value to this attribute to + sanitize the device to securely re-purpose or decommission it. + This is done by ensuring that all user data and meta-data, + whether it resides in persistent capacity, volatile capacity, + or the LSA, is made permanently unavailable by whatever means + is appropriate for the media type. This functionality requires + the device to be not be actively decoding any HPA ranges. + + +What /sys/bus/cxl/devices/memX/security/erase +Date: June, 2023 +KernelVersion: v6.5 +Contact: linux-cxl@vger.kernel.org +Description: + (WO) Write a boolean 'true' string value to this attribute to + secure erase user data by changing the media encryption keys for + all user data areas of the device. + + +What: /sys/bus/cxl/devices/memX/firmware/ +Date: April, 2023 +KernelVersion: v6.5 +Contact: linux-cxl@vger.kernel.org +Description: + (RW) Firmware uploader mechanism. The different files under + this directory can be used to upload and activate new + firmware for CXL devices. The interfaces under this are + documented in sysfs-class-firmware. + + What: /sys/bus/cxl/devices/*/devtype Date: June, 2021 KernelVersion: v5.14 diff --git a/Documentation/admin-guide/perf/cxl.rst b/Documentation/admin-guide/perf/cxl.rst new file mode 100644 index 000000000000..9233ea0d0b10 --- /dev/null +++ b/Documentation/admin-guide/perf/cxl.rst @@ -0,0 +1,68 @@ +.. SPDX-License-Identifier: GPL-2.0 + +====================================== +CXL Performance Monitoring Unit (CPMU) +====================================== + +The CXL rev 3.0 specification provides a definition of CXL Performance +Monitoring Unit in section 13.2: Performance Monitoring. + +CXL components (e.g. Root Port, Switch Upstream Port, End Point) may have +any number of CPMU instances. CPMU capabilities are fully discoverable from +the devices. The specification provides event definitions for all CXL protocol +message types and a set of additional events for things commonly counted on +CXL devices (e.g. DRAM events). + +CPMU driver +=========== + +The CPMU driver registers a perf PMU with the name pmu_mem<X>.<Y> on the CXL bus +representing the Yth CPMU for memX. + + /sys/bus/cxl/device/pmu_mem<X>.<Y> + +The associated PMU is registered as + + /sys/bus/event_sources/devices/cxl_pmu_mem<X>.<Y> + +In common with other CXL bus devices, the id has no specific meaning and the +relationship to specific CXL device should be established via the device parent +of the device on the CXL bus. + +PMU driver provides description of available events and filter options in sysfs. + +The "format" directory describes all formats of the config (event vendor id, +group id and mask) config1 (threshold, filter enables) and config2 (filter +parameters) fields of the perf_event_attr structure. The "events" directory +describes all documented events show in perf list. + +The events shown in perf list are the most fine grained events with a single +bit of the event mask set. More general events may be enable by setting +multiple mask bits in config. For example, all Device to Host Read Requests +may be captured on a single counter by setting the bits for all of + +* d2h_req_rdcurr +* d2h_req_rdown +* d2h_req_rdshared +* d2h_req_rdany +* d2h_req_rdownnodata + +Example of usage:: + + $#perf list + cxl_pmu_mem0.0/clock_ticks/ [Kernel PMU event] + cxl_pmu_mem0.0/d2h_req_rdshared/ [Kernel PMU event] + cxl_pmu_mem0.0/h2d_req_snpcur/ [Kernel PMU event] + cxl_pmu_mem0.0/h2d_req_snpdata/ [Kernel PMU event] + cxl_pmu_mem0.0/h2d_req_snpinv/ [Kernel PMU event] + ----------------------------------------------------------- + + $# perf stat -a -e cxl_pmu_mem0.0/clock_ticks/ -e cxl_pmu_mem0.0/d2h_req_rdshared/ + +Vendor specific events may also be available and if so can be used via + + $# perf stat -a -e cxl_pmu_mem0.0/vid=VID,gid=GID,mask=MASK/ + +The driver does not support sampling so "perf record" is unsupported. +It only supports system-wide counting so attaching to a task is +unsupported. diff --git a/Documentation/admin-guide/perf/index.rst b/Documentation/admin-guide/perf/index.rst index 9de64a40adab..f60be04e4e33 100644 --- a/Documentation/admin-guide/perf/index.rst +++ b/Documentation/admin-guide/perf/index.rst @@ -21,3 +21,4 @@ Performance monitor support alibaba_pmu nvidia-pmu meson-ddr-pmu + cxl |