Re: [PATCH v5] Add power/gpu_frequency tracepoint.

On Mon, Dec 21, 2020 at 12:10 PM Peiyong Lin lpy@google.com wrote:

Historically there is no common trace event for GPU frequency, in downstream Android each different hardware vendor implements their own way to expose GPU frequency, for example as a debugfs node. This patch standardize it as a common trace event in upstream linux kernel to help the ecosystem have a common implementation across hardware vendors. Toolings in the Linux ecosystem will benefit from this especially in the downstream Android, where this information is critical to graphics developers.

Signed-off-by: Peiyong Lin lpy@google.com

Changelog since v4:

• Explicitly use class id and instance id to identify a GPU instance.
• Change gpu_id to clock_id to call out its the clock domain in the GPU instance.

Changelog since v3:

• Correct copyright title.

Changelog since v2:

• Add more comments to indicate when the event should be emitted.
• Change state to frequency.

Changelog since v1:

• Use %u in TP_printk

drivers/gpu/Makefile | 1 + drivers/gpu/trace/Kconfig | 3 ++ drivers/gpu/trace/Makefile | 1 + drivers/gpu/trace/trace_gpu_frequency.c | 13 ++++++++ include/trace/events/power.h | 41 +++++++++++++++++++++++++ 5 files changed, 59 insertions(+) create mode 100644 drivers/gpu/trace/trace_gpu_frequency.c

diff --git a/drivers/gpu/Makefile b/drivers/gpu/Makefile index 835c88318cec..f289a47eb031 100644 --- a/drivers/gpu/Makefile +++ b/drivers/gpu/Makefile @@ -6,3 +6,4 @@ obj-$(CONFIG_TEGRA_HOST1X) += host1x/ obj-y += drm/ vga/ obj-$(CONFIG_IMX_IPUV3_CORE) += ipu-v3/ obj-$(CONFIG_TRACE_GPU_MEM) += trace/ +obj-$(CONFIG_TRACE_GPU_FREQUENCY) += trace/ diff --git a/drivers/gpu/trace/Kconfig b/drivers/gpu/trace/Kconfig index c24e9edd022e..ac4aec8d5845 100644 --- a/drivers/gpu/trace/Kconfig +++ b/drivers/gpu/trace/Kconfig @@ -2,3 +2,6 @@

config TRACE_GPU_MEM bool

+config TRACE_GPU_FREQUENCY

•   bool
  

diff --git a/drivers/gpu/trace/Makefile b/drivers/gpu/trace/Makefile index b70fbdc5847f..2b7ae69327d6 100644 --- a/drivers/gpu/trace/Makefile +++ b/drivers/gpu/trace/Makefile @@ -1,3 +1,4 @@ # SPDX-License-Identifier: GPL-2.0

obj-$(CONFIG_TRACE_GPU_MEM) += trace_gpu_mem.o +obj-$(CONFIG_TRACE_GPU_FREQUENCY) += trace_gpu_frequency.o diff --git a/drivers/gpu/trace/trace_gpu_frequency.c b/drivers/gpu/trace/trace_gpu_frequency.c new file mode 100644 index 000000000000..668fabd6b77a --- /dev/null +++ b/drivers/gpu/trace/trace_gpu_frequency.c @@ -0,0 +1,13 @@ +// SPDX-License-Identifier: GPL-2.0 +/*

• • GPU frequency trace points
• • Copyright (C) 2020 Google LLC
• */

+#include <linux/module.h>

+#define CREATE_TRACE_POINTS +#include <trace/events/power.h>

+EXPORT_TRACEPOINT_SYMBOL(gpu_frequency); diff --git a/include/trace/events/power.h b/include/trace/events/power.h index af5018aa9517..590e16169dd1 100644 --- a/include/trace/events/power.h +++ b/include/trace/events/power.h @@ -500,6 +500,47 @@ DEFINE_EVENT(dev_pm_qos_request, dev_pm_qos_remove_request,

    TP_ARGS(name, type, new_value)

);

+/**

• • gpu_frequency - Reports the GPU frequency in GPU clock domains.
• • This event should be emitted whenever there's a GPU frequency change happens,
• • or a GPU goes from idle state to active state, or vice versa.
• • When the GPU goes from idle state to active state, this event should report
• • the GPU frequency of the active state. When the GPU goes from active state to
• • idle state, this event should report a zero frequency value.
• • @frequency: New frequency (in KHz)
• • @gpu_class_id: Id representing the class of the GPU
• • @gpu_instance_id: Id representing the instance of class &gpu_class_id
• • @clock_id: Id for the clock domain in &gpu_instance_id running at &frequency
• */

+TRACE_EVENT(gpu_frequency,

•   TP_PROTO(unsigned int frequency, unsigned int gpu_class_id,
  

•            unsigned int gpu_instance_id, unsigned int clock_id),
  

•   TP_ARGS(frequency, gpu_class_id, gpu_instance_id, clock_id),
  

•   TP_STRUCT__entry(
  

•           __field(unsigned int, frequency)
  

•           __field(unsigned int, gpu_class_id)
  

•           __field(unsigned int, gpu_instance_id)
  

•           __field(unsigned int, clock_id)
  

•   ),
  

•   TP_fast_assign(
  

•           __entry->frequency = frequency;
  

•           __entry->gpu_class_id = gpu_class_id;
  

•           __entry->gpu_instance_id = gpu_instance_id;
  

•           __entry->clock_id = clock_id;
  

•   ),
  

•   TP_printk("frequency=%u gpu_class_id=%u gpu_instance_id=%u clock_id=%u",
  

•           __entry->frequency, __entry->gpu_class_id,
  

•           __entry->gpu_instance_id, __entry->clock_id)
  

+); #endif /* _TRACE_POWER_H */

/* This part must be outside protection */

2.29.2.684.gfbc64c5ab5-goog

Hi there,

Could you please take a look at this patch?

Thanks, Peiyong