diff options
Diffstat (limited to 'Documentation/gpu')
| -rw-r--r-- | Documentation/gpu/amdgpu/amdgpu-glossary.rst | 13 | ||||
| -rw-r--r-- | Documentation/gpu/drm-usage-stats.rst | 112 | ||||
| -rw-r--r-- | Documentation/gpu/i915.rst | 28 | ||||
| -rw-r--r-- | Documentation/gpu/index.rst | 1 |
4 files changed, 154 insertions, 0 deletions
diff --git a/Documentation/gpu/amdgpu/amdgpu-glossary.rst b/Documentation/gpu/amdgpu/amdgpu-glossary.rst index 859dcec6c6f9..db924d37f93e 100644 --- a/Documentation/gpu/amdgpu/amdgpu-glossary.rst +++ b/Documentation/gpu/amdgpu/amdgpu-glossary.rst @@ -8,12 +8,19 @@ we have a dedicated glossary for Display Core at .. glossary:: + active_cu_number + The number of CUs that are active on the system. The number of active + CUs may be less than SE * SH * CU depending on the board configuration. + CP Command Processor CPLIB Content Protection Library + CU + Compute Unit + DFS Digital Frequency Synthesizer @@ -74,6 +81,12 @@ we have a dedicated glossary for Display Core at SDMA System DMA + SE + Shader Engine + + SH + SHader array + SMU System Management Unit diff --git a/Documentation/gpu/drm-usage-stats.rst b/Documentation/gpu/drm-usage-stats.rst new file mode 100644 index 000000000000..6c9f166a8d6f --- /dev/null +++ b/Documentation/gpu/drm-usage-stats.rst @@ -0,0 +1,112 @@ +.. _drm-client-usage-stats: + +====================== +DRM client usage stats +====================== + +DRM drivers can choose to export partly standardised text output via the +`fops->show_fdinfo()` as part of the driver specific file operations registered +in the `struct drm_driver` object registered with the DRM core. + +One purpose of this output is to enable writing as generic as practicaly +feasible `top(1)` like userspace monitoring tools. + +Given the differences between various DRM drivers the specification of the +output is split between common and driver specific parts. Having said that, +wherever possible effort should still be made to standardise as much as +possible. + +File format specification +========================= + +- File shall contain one key value pair per one line of text. +- Colon character (`:`) must be used to delimit keys and values. +- All keys shall be prefixed with `drm-`. +- Whitespace between the delimiter and first non-whitespace character shall be + ignored when parsing. +- Neither keys or values are allowed to contain whitespace characters. +- Numerical key value pairs can end with optional unit string. +- Data type of the value is fixed as defined in the specification. + +Key types +--------- + +1. Mandatory, fully standardised. +2. Optional, fully standardised. +3. Driver specific. + +Data types +---------- + +- <uint> - Unsigned integer without defining the maximum value. +- <str> - String excluding any above defined reserved characters or whitespace. + +Mandatory fully standardised keys +--------------------------------- + +- drm-driver: <str> + +String shall contain the name this driver registered as via the respective +`struct drm_driver` data structure. + +Optional fully standardised keys +-------------------------------- + +- drm-pdev: <aaaa:bb.cc.d> + +For PCI devices this should contain the PCI slot address of the device in +question. + +- drm-client-id: <uint> + +Unique value relating to the open DRM file descriptor used to distinguish +duplicated and shared file descriptors. Conceptually the value should map 1:1 +to the in kernel representation of `struct drm_file` instances. + +Uniqueness of the value shall be either globally unique, or unique within the +scope of each device, in which case `drm-pdev` shall be present as well. + +Userspace should make sure to not double account any usage statistics by using +the above described criteria in order to associate data to individual clients. + +- drm-engine-<str>: <uint> ns + +GPUs usually contain multiple execution engines. Each shall be given a stable +and unique name (str), with possible values documented in the driver specific +documentation. + +Value shall be in specified time units which the respective GPU engine spent +busy executing workloads belonging to this client. + +Values are not required to be constantly monotonic if it makes the driver +implementation easier, but are required to catch up with the previously reported +larger value within a reasonable period. Upon observing a value lower than what +was previously read, userspace is expected to stay with that larger previous +value until a monotonic update is seen. + +- drm-engine-capacity-<str>: <uint> + +Engine identifier string must be the same as the one specified in the +drm-engine-<str> tag and shall contain a greater than zero number in case the +exported engine corresponds to a group of identical hardware engines. + +In the absence of this tag parser shall assume capacity of one. Zero capacity +is not allowed. + +- drm-memory-<str>: <uint> [KiB|MiB] + +Each possible memory type which can be used to store buffer objects by the +GPU in question shall be given a stable and unique name to be returned as the +string here. + +Value shall reflect the amount of storage currently consumed by the buffer +object belong to this client, in the respective memory region. + +Default unit shall be bytes with optional unit specifiers of 'KiB' or 'MiB' +indicating kibi- or mebi-bytes. + +=============================== +Driver specific implementations +=============================== + +:ref:`i915-usage-stats` diff --git a/Documentation/gpu/i915.rst b/Documentation/gpu/i915.rst index 0f08693d05cd..54060cd6c419 100644 --- a/Documentation/gpu/i915.rst +++ b/Documentation/gpu/i915.rst @@ -697,3 +697,31 @@ The style guide for ``i915_reg.h``. .. kernel-doc:: drivers/gpu/drm/i915/i915_reg.h :doc: The i915 register macro definition style guide + +.. _i915-usage-stats: + +i915 DRM client usage stats implementation +========================================== + +The drm/i915 driver implements the DRM client usage stats specification as +documented in :ref:`drm-client-usage-stats`. + +Example of the output showing the implemented key value pairs and entirety of +the currently possible format options: + +:: + + pos: 0 + flags: 0100002 + mnt_id: 21 + drm-driver: i915 + drm-pdev: 0000:00:02.0 + drm-client-id: 7 + drm-engine-render: 9288864723 ns + drm-engine-copy: 2035071108 ns + drm-engine-video: 0 ns + drm-engine-capacity-video: 2 + drm-engine-video-enhance: 0 ns + +Possible `drm-engine-` key names are: `render`, `copy`, `video` and +`video-enhance`. diff --git a/Documentation/gpu/index.rst b/Documentation/gpu/index.rst index b9c1214d8f23..b99dede9a5b1 100644 --- a/Documentation/gpu/index.rst +++ b/Documentation/gpu/index.rst @@ -10,6 +10,7 @@ Linux GPU Driver Developer's Guide drm-kms drm-kms-helpers drm-uapi + drm-usage-stats driver-uapi drm-client drivers |