[RFC PATCH 0/2] drm: use dynamic_debug

From: Jim Cromie
Date: Thu Dec 03 2020 - 22:54:27 EST


hello gentle readers,

These 2 rfc patches convert part of drm-world to use dynamic debug.

1st one addresses drm.debug category based logging. If DYNAMIC_DEBUG
is configured, then CONFIG_DRM_USE_DYNAMIC_DEBUG controls whether
dynamic-debug is used to avoid runtime costs of drm_debug_enabled().
We require CONFIG_JUMP_LABEL too, since we are selling its
optimization.

This change adds many new callsites to /proc/dynamic_debug/control;
~300 in drm, ~200 in drm_kms_helper, as well as ~1500 in i915 driver,
and ~3200 in amdgpu. So there are substantial implications here.

2nd one is for i915, which I have in my laptop. `grep pr_debug` found
~90 callsites with a meaningful format-prefix-string, to demonstrate
use of "format ^prefix" to control user categorized debugs.

Jim Cromie (2):
drm: RFC add choice to use dynamic debug in drm-debug
i915: POC use dynamic_debug_exec_queries to control pr_debugs in gvt

drivers/gpu/drm/Kconfig | 13 +++++
drivers/gpu/drm/drm_print.c | 75 ++++++++++++++++++++++--
drivers/gpu/drm/i915/gvt/Makefile | 1 +
drivers/gpu/drm/i915/i915_params.c | 74 ++++++++++++++++++++++++
include/drm/drm_print.h | 92 ++++++++++++++++++++++--------
5 files changed, 228 insertions(+), 27 deletions(-)

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2.28.0