On Wed, Apr 12, 2023 at 01:36:52AM +0300, Dmitry Baryshkov wrote: > On 11/04/2023 21:28, Rob Clark wrote: > > On Tue, Apr 11, 2023 at 10:36 AM Dmitry Baryshkov > > <dmitry.barysh...@linaro.org> wrote: > > > > > > On Tue, 11 Apr 2023 at 20:13, Rob Clark <robdcl...@gmail.com> wrote: > > > > > > > > On Tue, Apr 11, 2023 at 9:53 AM Daniel Vetter <dan...@ffwll.ch> wrote: > > > > > > > > > > On Tue, Apr 11, 2023 at 09:47:32AM -0700, Rob Clark wrote: > > > > > > On Mon, Apr 10, 2023 at 2:06 PM Rob Clark <robdcl...@gmail.com> > > > > > > wrote: > > > > > > > > > > > > > > From: Rob Clark <robdcl...@chromium.org> > > > > > > > > > > > > > > Similar motivation to other similar recent attempt[1]. But with > > > > > > > an > > > > > > > attempt to have some shared code for this. As well as > > > > > > > documentation. > > > > > > > > > > > > > > It is probably a bit UMA-centric, I guess devices with VRAM might > > > > > > > want > > > > > > > some placement stats as well. But this seems like a reasonable > > > > > > > start. > > > > > > > > > > > > > > Basic gputop support: > > > > > > > https://patchwork.freedesktop.org/series/116236/ > > > > > > > And already nvtop support: https://github.com/Syllo/nvtop/pull/204 > > > > > > > > > > > > On a related topic, I'm wondering if it would make sense to report > > > > > > some more global things (temp, freq, etc) via fdinfo? Some of this, > > > > > > tools like nvtop could get by trawling sysfs or other driver > > > > > > specific > > > > > > ways. But maybe it makes sense to have these sort of things > > > > > > reported > > > > > > in a standardized way (even though they aren't really per-drm_file) > > > > > > > > > > I think that's a bit much layering violation, we'd essentially have to > > > > > reinvent the hwmon sysfs uapi in fdinfo. Not really a business I want > > > > > to > > > > > be in :-) > > > > > > > > I guess this is true for temp (where there are thermal zones with > > > > potentially multiple temp sensors.. but I'm still digging my way thru > > > > the thermal_cooling_device stuff) > > > > > > It is slightly ugly. All thermal zones and cooling devices are virtual > > > devices (so, even no connection to the particular tsens device). One > > > can either enumerate them by checking > > > /sys/class/thermal/thermal_zoneN/type or enumerate them through > > > /sys/class/hwmon. For cooling devices again the only enumeration is > > > through /sys/class/thermal/cooling_deviceN/type. > > > > > > Probably it should be possible to push cooling devices and thermal > > > zones under corresponding providers. However I do not know if there is > > > a good way to correlate cooling device (ideally a part of GPU) to the > > > thermal_zone (which in our case is provided by tsens / temp_alarm > > > rather than GPU itself). > > > > > > > > > > > But what about freq? I think, esp for cases where some "fw thing" is > > > > controlling the freq we end up needing to use gpu counters to measure > > > > the freq. > > > > > > For the freq it is slightly easier: /sys/class/devfreq/*, devices are > > > registered under proper parent (IOW, GPU). So one can read > > > /sys/class/devfreq/3d00000.gpu/cur_freq or > > > /sys/bus/platform/devices/3d00000.gpu/devfreq/3d00000.gpu/cur_freq. > > > > > > However because of the components usage, there is no link from > > > /sys/class/drm/card0 > > > (/sys/devices/platform/soc@0/ae00000.display-subsystem/ae01000.display-controller/drm/card0) > > > to /sys/devices/platform/soc@0/3d00000.gpu, the GPU unit. > > > > > > Getting all these items together in a platform-independent way would > > > be definitely an important but complex topic. > > > > But I don't believe any of the pci gpu's use devfreq ;-) > > > > And also, you can't expect the CPU to actually know the freq when fw > > is the one controlling freq. We can, currently, have a reasonable > > approximation from devfreq but that stops if IFPC is implemented. And > > other GPUs have even less direct control. So freq is a thing that I > > don't think we should try to get from "common frameworks" > > I think it might be useful to add another passive devfreq governor type for > external frequencies. This way we can use the same interface to export > non-CPU-controlled frequencies.
Yeah this sounds like a decent idea to me too. It might also solve the fun of various pci devices having very non-standard freq controls in sysfs (looking at least at i915 here ...) I guess it would minimally be a good idea if we could document this, or maybe have a reference implementation in nvtop or whatever the cool thing is rn. -Daniel > > > > > BR, > > -R > > > > > > > > > > > What might be needed is better glue to go from the fd or fdinfo to the > > > > > right hw device and then crawl around the hwmon in sysfs > > > > > automatically. I > > > > > would not be surprised at all if we really suck on this, probably more > > > > > likely on SoC than pci gpus where at least everything should be under > > > > > the > > > > > main pci sysfs device. > > > > > > > > yeah, I *think* userspace would have to look at /proc/device-tree to > > > > find the cooling device(s) associated with the gpu.. at least I don't > > > > see a straightforward way to figure it out just for sysfs > > > > > > > > BR, > > > > -R > > > > > > > > > -Daniel > > > > > > > > > > > > > > > > > BR, > > > > > > -R > > > > > > > > > > > > > > > > > > > [1] https://patchwork.freedesktop.org/series/112397/ > > > > > > > > > > > > > > Rob Clark (2): > > > > > > > drm: Add fdinfo memory stats > > > > > > > drm/msm: Add memory stats to fdinfo > > > > > > > > > > > > > > Documentation/gpu/drm-usage-stats.rst | 21 +++++++ > > > > > > > drivers/gpu/drm/drm_file.c | 79 > > > > > > > +++++++++++++++++++++++++++ > > > > > > > drivers/gpu/drm/msm/msm_drv.c | 25 ++++++++- > > > > > > > drivers/gpu/drm/msm/msm_gpu.c | 2 - > > > > > > > include/drm/drm_file.h | 10 ++++ > > > > > > > 5 files changed, 134 insertions(+), 3 deletions(-) > > > > > > > > > > > > > > -- > > > > > > > 2.39.2 > > > > > > > > > > > > > > > > > -- > > > > > Daniel Vetter > > > > > Software Engineer, Intel Corporation > > > > > http://blog.ffwll.ch > > > > > > > > > > > > -- > > > With best wishes > > > Dmitry > > -- > With best wishes > Dmitry > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch