[RFC] ANDROID: GPU frequency tracing support #28
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ssebinraj
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| goto err_free_tracer; | ||
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| /* Allocate GT data array - assume max 2 GTs for now */ |
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Can we read GTs count rather than doing hardcoding? May be we can implement some function to read it.
| return -EOPNOTSUPP; | ||
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| if (gt->info.id >= 2) { /* Assume max 2 GTs */ |
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once you have the way to read GTs count, we can remove this hardcoding
| struct xe_gpufreqtracer_data *tracer_data = gt_to_xe(gt)->gpufreqtracer_data; | ||
| struct xe_gpufreqtracer_gt_data *gt_data; | ||
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| if (!tracer_data || gt->info.id >= 2) { |
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same comment. we can remove the hardcoding once we implement function to read GTs count
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| gt_data->monitoring_active = false; | ||
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| timer_delete(>_data->timer); |
| * This function is executed in a workqueue context to periodically sample | ||
| * the GPU frequency and perform any necessary tracing or logging operations. | ||
| * It is part of the GPU frequency tracer subsystem. | ||
| */ |
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do we need to create dedicated work queue? we can use system_highpri_wq a global workqueue provided by the kernel.
upstream people might ask this questions. Lets have a proper reason for the same.
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As per the comment code has been modified.
| * | ||
| * location: /d/events/power/gpu_frequency | ||
| * format: {unsigned int state, unsigned int gpu_id} | ||
| * where state holds the frequency(in Khz) and the gpu_id holds the GPU clock domain. |
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Tracepoint uses state for frequency. Consider using more descriptive field names in the tracepoint like freq_khz
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Yes that's right, but this is as per the spec shared by google, they require it in such format.
drivers/gpu/drm/xe/xe_module.c
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| static int xe_validate_module_params(void) | ||
| { | ||
| /* Validate GPU frequency monitoring interval */ | ||
| if (xe_modparam.gpufreq_monitoring_interval_ms < 100 || |
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drivers/gpu/drm/xe/xe_device.c
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| xe_device_remove_display(xe); | ||
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| #ifdef CONFIG_DRM_GPUFREQTRACER |
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#ifdef CONFIG_DRM_GPUFREQTRACER (missing XE). Have a look
| current_freq = xe_guc_pc_get_act_freq(pc) * 1000; /* Convert MHz to KHz */ | ||
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| /* Only report if frequency has changed or this is the first sample */ | ||
| if (current_freq != gt_data->last_frequency) { |
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just check if there is concurrency problem. If yes use atomic or protect by some lock. Similarly for last_frequency.
A periodic GPU frequency monitoring and tracing program for the
Xe driver. The implementation provides bothperiodic sampling and
event-driven frequency change notifications through the Linux
ftrace infrastructure.
Key features:
- Periodic GPU frequency sampling with configurable intervals
- Immediate frequency change reporting via tracepoints
- Integration with Linux ftrace subsystem under 'power' events
- Per-GT (Graphics Technology) monitoring support
- Dedicated workqueue for non-blocking frequency sampling
- Configurable via CONFIG_DRM_XE_GPUFREQTRACER kernel option
- The monitoring interval can be configured at runtime via the sysfs
(default 5sec).
The sysfs entry is at:
/sys/module/xe/parameters/gpufreq_monitoring_interval_ms
The tracepoint is exposed at:
/sys/kernel/debug/tracing/events/power/gpu_frequency
Format: {unsigned int state, unsigned int gpu_id}
- state: GPU frequency in KHz
- gpu_id: GPU clock domain identifier
This enables userspace tools and system monitoring applications to track
GPU frequency changes for power management analysis, performance tuning,
and debugging purposes.
Bug: 388282937
Test: CtsGpuProfilingDataTestCases
Change-Id: I7e8025004abd4b3ffdfb4d7214a4b4896be95a64
Signed-off-by: S Sebinraj <[email protected]>
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A periodic GPU frequency monitoring and tracing program for the Xe driver. The implementation provides bothperiodic sampling and event-driven frequency change notifications through the Linux ftrace infrastructure.
Key features:
The sysfs entry is at:
/sys/module/xe/parameters/gpufreq_monitoring_interval_ms
The tracepoint is exposed at:
/sys/kernel/debug/tracing/events/power/gpu_frequency
Format: {unsigned int state, unsigned int gpu_id}
This enables userspace tools and system monitoring applications to track GPU frequency changes for power management analysis, performance tuning, and debugging purposes.
Bug: 388282937
Change-Id: I7e8025004abd4b3ffdfb4d7214a4b4896be95a64