[PATCH V3 00/23] drm/etnaviv: support performance counters

[Christian Gmeiner]

2017-08-25 11:06 GMT+02:00 Christian Gmeiner <christian.gmeiner at gmail.com>:
> In a perfect world we would be able to read GPU registers of interest
> via the command stream with a 'read-register' command/package. For perf
> counters it is a must to read them synchronized with the GPU to put the
> values in relation to a draw command. As Vivante GPUs do not provide this
> functionality we need to emulate it in software.
>
>
> We need to support three different kind of perf register types:
>
> 1) normal register
>   This is the easierst case where we can simply read the register and we
>   are done.
>
> 2) debug register
>   We need to configure the mux register and then read the debug register value.
>
> 3) pipeline register
>   We need to 'iterate' over all pixel pipes and sum up the values. The 'iteration'
>   is done by select the pipe of interest via HI_CLOCK_CONTROL_DEBUG_PIXEL_PIPE.
>   There is also need to configure the mux register.
>
>
> Allowing the userspace to do it all by its own feels quite error prone and not
> future-proof. Thats why the kernel exports all performance domains and their
> signals to the userspace via two new ioctls. So the kernel knows all performance
> counters and how to sample them.
>
> At the moment all performacne domains and signals get exported to all gpu pipe types,
> but that can be changed in follow-up patches.
>
> struct drm_etnaviv_gem_submit was extended to include so-called performance monitor
> requests (pmrs). A request defines what domain and signal should be sampled (pre/post
> draw cmdbuffer) and where to store the result.
>
> The whole series can be found here:
> https://github.com/austriancoder/linux/tree/perfmon-v3
>
> The used libdrm and mesa branches to test this feature can be found here:
> https://github.com/austriancoder/libdrm/commits/perfmon-v2
> https://github.com/austriancoder/mesa/commits/perfmon-v2
>
> Changes v1 -> v2:
>  - reworked events
>  - reworked uapi
>  - reworked enumeration of domains and signals
>  - process sync point with a work item to keep irq as fast as possible
>  - prevent GPU hang when reading pixel pipeline perf values
>  - all SH perf counters are accessed via perf_reg_read(..)
>
> Changes v2 -> v3:
>  - reworked alloc_event(..)
>  - fixed pmr flag validation
>
> Happy reviewing!
>
> Christian Gmeiner (23):
>   drm/etnaviv: use bitmap to keep track of events
>   drm/etnaviv: make it possible to allocate multiple events
>   drm/etnaviv: add infrastructure to query perf counter
>   drm/etnaviv: add uapi for perfmon feature
>   drm/etnaviv: add internal representation of perfmon_request
>   drm/etnaviv: extend etnaviv_gpu_cmdbuf_new(..) with nr_pmrs
>   drm/etnaviv: add performance monitor request validation
>   drm/etnaviv: copy pmrs from userspace
>   drm/etnaviv: add performance monitor request processing
>   drm/etnaviv: add 'sync point' support
>   drm/etnaviv: clear alloced event
>   drm/etnaviv: use 'sync points' for performance monitor requests
>   drm/etnaviv: add HI perf domain
>   drm/etnaviv: add PE perf domain
>   drm/etnaviv: add SH perf domain
>   drm/etnaviv: add PA perf domain
>   drm/etnaviv: add SE perf domain
>   drm/etnaviv: add RA perf domain
>   drm/etnaviv: add TX perf domain
>   drm/etnaviv: add MC perf domain
>   drm/etnaviv: need to disable clock gating when doing profiling
>   drm/etnaviv: enable debug registers on demand
>   drm/etnaviv: submit supports performance monitor requests
>
>  drivers/gpu/drm/etnaviv/Makefile             |   3 +-
>  drivers/gpu/drm/etnaviv/etnaviv_buffer.c     |  36 +++
>  drivers/gpu/drm/etnaviv/etnaviv_cmdbuf.c     |  15 +-
>  drivers/gpu/drm/etnaviv/etnaviv_cmdbuf.h     |   6 +-
>  drivers/gpu/drm/etnaviv/etnaviv_drv.c        |  39 ++-
>  drivers/gpu/drm/etnaviv/etnaviv_drv.h        |   1 +
>  drivers/gpu/drm/etnaviv/etnaviv_gem_submit.c |  69 ++++-
>  drivers/gpu/drm/etnaviv/etnaviv_gpu.c        | 216 ++++++++++---
>  drivers/gpu/drm/etnaviv/etnaviv_gpu.h        |  13 +-
>  drivers/gpu/drm/etnaviv/etnaviv_perfmon.c    | 447 +++++++++++++++++++++++++++
>  drivers/gpu/drm/etnaviv/etnaviv_perfmon.h    |  48 +++
>  include/uapi/drm/etnaviv_drm.h               |  42 ++-
>  12 files changed, 878 insertions(+), 57 deletions(-)
>  create mode 100644 drivers/gpu/drm/etnaviv/etnaviv_perfmon.c
>  create mode 100644 drivers/gpu/drm/etnaviv/etnaviv_perfmon.h
>
> --

It looks like I have screwed up patches 03 and 04 - used v1 ones
instead of v2 :/
I will send out a tested v4 series on Tuesday next week as I am
currently in Sweden
and my device @home did not survived a reboot.

Sorry if I wasted somebody's time.
--
Christian Gmeiner, MSc

https://christian-gmeiner.info