diff options
Diffstat (limited to 'Documentation/gpu')
-rw-r--r-- | Documentation/gpu/drm-compute.rst | 54 | ||||
-rw-r--r-- | Documentation/gpu/drm-kms-helpers.rst | 3 | ||||
-rw-r--r-- | Documentation/gpu/drm-usage-stats.rst | 54 | ||||
-rw-r--r-- | Documentation/gpu/index.rst | 1 | ||||
-rw-r--r-- | Documentation/gpu/xe/index.rst | 1 | ||||
-rw-r--r-- | Documentation/gpu/xe/xe_devcoredump.rst | 14 | ||||
-rw-r--r-- | Documentation/gpu/zynqmp.rst | 2 |
7 files changed, 100 insertions, 29 deletions
diff --git a/Documentation/gpu/drm-compute.rst b/Documentation/gpu/drm-compute.rst new file mode 100644 index 000000000000..f90c3e63aa9e --- /dev/null +++ b/Documentation/gpu/drm-compute.rst @@ -0,0 +1,54 @@ +================================== +Long running workloads and compute +================================== + +Long running workloads (compute) are workloads that will not complete in 10 +seconds. (The time let the user wait before he reaches for the power button). +This means that other techniques need to be used to manage those workloads, +that cannot use fences. + +Some hardware may schedule compute jobs, and have no way to pre-empt them, or +have their memory swapped out from them. Or they simply want their workload +not to be preempted or swapped out at all. + +This means that it differs from what is described in driver-api/dma-buf.rst. + +As with normal compute jobs, dma-fence may not be used at all. In this case, +not even to force preemption. The driver with is simply forced to unmap a BO +from the long compute job's address space on unbind immediately, not even +waiting for the workload to complete. Effectively this terminates the workload +when there is no hardware support to recover. + +Since this is undesirable, there need to be mitigations to prevent a workload +from being terminated. There are several possible approach, all with their +advantages and drawbacks. + +The first approach you will likely try is to pin all buffers used by compute. +This guarantees that the job will run uninterrupted, but also allows a very +denial of service attack by pinning as much memory as possible, hogging the +all GPU memory, and possibly a huge chunk of CPU memory. + +A second approach that will work slightly better on its own is adding an option +not to evict when creating a new job (any kind). If all of userspace opts in +to this flag, it would prevent cooperating userspace from forced terminating +older compute jobs to start a new one. + +If job preemption and recoverable pagefaults are not available, those are the +only approaches possible. So even with those, you want a separate way of +controlling resources. The standard kernel way of doing so is cgroups. + +This creates a third option, using cgroups to prevent eviction. Both GPU and +driver-allocated CPU memory would be accounted to the correct cgroup, and +eviction would be made cgroup aware. This allows the GPU to be partitioned +into cgroups, that will allow jobs to run next to each other without +interference. + +The interface to the cgroup would be similar to the current CPU memory +interface, with similar semantics for min/low/high/max, if eviction can +be made cgroup aware. + +What should be noted is that each memory region (tiled memory for example) +should have its own accounting. + +The key is set to the regionid set by the driver, for example "tile0". +For the value of $card, we use drmGetUnique(). diff --git a/Documentation/gpu/drm-kms-helpers.rst b/Documentation/gpu/drm-kms-helpers.rst index 8cf2f041af47..b4ee25af1702 100644 --- a/Documentation/gpu/drm-kms-helpers.rst +++ b/Documentation/gpu/drm-kms-helpers.rst @@ -221,6 +221,9 @@ Panel Helper Reference .. kernel-doc:: drivers/gpu/drm/drm_panel_orientation_quirks.c :export: +.. kernel-doc:: drivers/gpu/drm/drm_panel_backlight_quirks.c + :export: + Panel Self Refresh Helper Reference =================================== diff --git a/Documentation/gpu/drm-usage-stats.rst b/Documentation/gpu/drm-usage-stats.rst index 2717cb2a597e..b7fc106dad99 100644 --- a/Documentation/gpu/drm-usage-stats.rst +++ b/Documentation/gpu/drm-usage-stats.rst @@ -145,57 +145,57 @@ both. Memory ^^^^^^ -- drm-memory-<region>: <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. +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 used as the "<region>" +string. The region name "memory" is reserved to refer to normal system memory. -Value shall reflect the amount of storage currently consumed by the buffer +The value shall reflect the amount of storage currently consumed by the buffer objects 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. -This key is deprecated and is an alias for drm-resident-<region>. Only one of -the two should be present in the output. - -- drm-shared-<region>: <uint> [KiB|MiB] +- drm-total-<region>: <uint> [KiB|MiB] -The total size of buffers that are shared with another file (e.g., have more -than a single handle). +The total size of all requested buffers, including both shared and private +memory. The backing store for the buffers does not need to be currently +instantiated to count under this category. To avoid double-counting, if a buffer +has multiple regions where it can be allocated to, the implementation should +consistently select a single region for accounting purposes. -- drm-total-<region>: <uint> [KiB|MiB] +- drm-shared-<region>: <uint> [KiB|MiB] -The total size of all created buffers including shared and private memory. The -backing store for the buffers does not have to be currently instantiated to be -counted under this category. +The total size of buffers that are shared with another file (i.e., have more +than one handle). The same requirement to avoid double-counting that applies to +drm-total-<region> also applies here. - drm-resident-<region>: <uint> [KiB|MiB] -The total size of buffers that are resident (have their backing store present or -instantiated) in the specified region. +The total size of buffers that are resident (i.e., have their backing store +present or instantiated) in the specified region. + +- drm-memory-<region>: <uint> [KiB|MiB] -This is an alias for drm-memory-<region> and only one of the two should be -present in the output. +This key is deprecated and is only printed by amdgpu; it is an alias for +drm-resident-<region>. - drm-purgeable-<region>: <uint> [KiB|MiB] -The total size of buffers that are purgeable. +The total size of buffers that are resident and purgeable. -For example drivers which implement a form of 'madvise' like functionality can -here count buffers which have instantiated backing store, but have been marked -with an equivalent of MADV_DONTNEED. +For example, drivers that implement functionality similar to 'madvise' can count +buffers that have instantiated backing stores but have been marked with an +equivalent of MADV_DONTNEED. - drm-active-<region>: <uint> [KiB|MiB] The total size of buffers that are active on one or more engines. -One practical example of this can be presence of unsignaled fences in an GEM -buffer reservation object. Therefore the active category is a subset of -resident. +One practical example of this could be the presence of unsignaled fences in a +GEM buffer reservation object. Therefore, the active category is a subset of the +resident category. Implementation Details ====================== diff --git a/Documentation/gpu/index.rst b/Documentation/gpu/index.rst index 37e383ccf73f..7dcb15850afd 100644 --- a/Documentation/gpu/index.rst +++ b/Documentation/gpu/index.rst @@ -13,6 +13,7 @@ GPU Driver Developer's Guide drm-usage-stats driver-uapi drm-client + drm-compute drivers backlight vga-switcheroo diff --git a/Documentation/gpu/xe/index.rst b/Documentation/gpu/xe/index.rst index 3f07aa3b5432..92cfb25e64d3 100644 --- a/Documentation/gpu/xe/index.rst +++ b/Documentation/gpu/xe/index.rst @@ -23,4 +23,5 @@ DG2, etc is provided to prototype the driver. xe_firmware xe_tile xe_debugging + xe_devcoredump xe-drm-usage-stats.rst diff --git a/Documentation/gpu/xe/xe_devcoredump.rst b/Documentation/gpu/xe/xe_devcoredump.rst new file mode 100644 index 000000000000..ae4ec0e34dc0 --- /dev/null +++ b/Documentation/gpu/xe/xe_devcoredump.rst @@ -0,0 +1,14 @@ +.. SPDX-License-Identifier: (GPL-2.0+ OR MIT) + +================== +Xe Device Coredump +================== + +.. kernel-doc:: drivers/gpu/drm/xe/xe_devcoredump.c + :doc: Xe device coredump + +Internal API +============ + +.. kernel-doc:: drivers/gpu/drm/xe/xe_devcoredump.c + :internal: diff --git a/Documentation/gpu/zynqmp.rst b/Documentation/gpu/zynqmp.rst index f57bfa0ad6ec..1a6f9193de22 100644 --- a/Documentation/gpu/zynqmp.rst +++ b/Documentation/gpu/zynqmp.rst @@ -144,6 +144,4 @@ Internals .. kernel-doc:: drivers/gpu/drm/xlnx/zynqmp_dp.c -.. kernel-doc:: drivers/gpu/drm/xlnx/zynqmp_dpsub.c - .. kernel-doc:: drivers/gpu/drm/xlnx/zynqmp_kms.c |