[PATCH v5 00/13] drm/trace: Mirror DRM debug logs to tracefs

[Sean Paul]

On Mon, Jun 8, 2020 at 5:05 PM Sean Paul <sean at poorly.run> wrote:
>
> From: Sean Paul <seanpaul at chromium.org>
>
> This series is the latest in my journey to create a lightweight,
> always-on "flight recorder" (name credit Weston) of drm logs. This
> incarnation uses a trace_array to keep logs in memory exposed through
> tracefs. Users and distros can enable drm logs by using the drm.trace
> module parameter to choose the debug categories they are interested in.
>
> The set has ballooned a little bit since the last version. Reason being
> is that I decided to return true from drm_debug_enabled if trace was
> enabled. This should make it easier and more seamless for driver
> developers to use the correct interface, but meant I needed to audit all
> uses of drm_debug_enabled and drm_debug_printer.
>
> Out of all those calls, there are 3 situations which arose:
> 1- The logs should only go to syslog:
>         I've converted these to use the drm_debug_syslog variant of
>         enable check/printer.
>
> 2- The logs should go to both syslog/trace, but were using pr_debug():
>         I've converted these to use the proper drm logging helper. In
>         cases which used a drm_printer I've had to use a new
>         drm_debug_category_printer to ensure they are routed correctly.
>
> 3- The logs should go to both syslog/trace and are using drm logging fns:
>         These are untouched and should be routed to the appropriate
>         place(s)
>

Friendly ping. Is this something upstream wants, or should we continue
carrying it downstream?

Sean

>
> Sean Paul (13):
>   drm/mipi_dbi: Convert pr_debug calls to DRM_DEBUG_DRIVER
>   drm/sil164: Convert dev_printk to drm_dev_dbg
>   drm/i915/utils: Replace dev_printk with drm helpers
>   drm/msm/dpu: Replace definitions for dpu debug macros
>   drm/print: rename drm_debug* to be more syslog-centric
>   drm/amd: Gate i2c transaction logs on drm_debug_syslog
>   drm/etnaviv: Change buffer dump checks to target syslog
>   drm/nouveau: Change debug checks to specifically target syslog
>   drm/i915: Change infoframe debug checks to specify syslog
>   drm/print: Add drm_debug_category_printer
>   drm/mst: Convert debug printers to debug category printers
>   drm/i915: Use debug category printer for welcome message
>   drm/print: Add tracefs support to the drm logging helpers
>
>  Documentation/gpu/drm-uapi.rst               |   6 +
>  drivers/gpu/drm/amd/amdgpu/smu_v11_0_i2c.c   |   4 +-
>  drivers/gpu/drm/drm_dp_mst_topology.c        |   9 +-
>  drivers/gpu/drm/drm_drv.c                    |   3 +
>  drivers/gpu/drm/drm_mipi_dbi.c               |   8 +-
>  drivers/gpu/drm/drm_print.c                  | 228 ++++++++++++++++---
>  drivers/gpu/drm/etnaviv/etnaviv_buffer.c     |   8 +-
>  drivers/gpu/drm/i2c/sil164_drv.c             |  12 +-
>  drivers/gpu/drm/i915/display/intel_display.c |   4 +-
>  drivers/gpu/drm/i915/i915_drv.c              |   3 +-
>  drivers/gpu/drm/i915/i915_utils.c            |   5 +-
>  drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h      |  20 +-
>  drivers/gpu/drm/nouveau/dispnv50/disp.h      |   4 +-
>  drivers/gpu/drm/nouveau/nouveau_drv.h        |   4 +-
>  include/drm/drm_print.h                      |  96 +++++++-
>  15 files changed, 318 insertions(+), 96 deletions(-)
>
> --
> Sean Paul, Software Engineer, Google / Chromium OS
>