kernel/linux.git/drivers/gpu/drm/drm_print.c, branch linux-6.9.y

drm: remove drm_debug_printer in favor of drm_dbg_printer

2024-02-09T09:52:43+00:00

Convert the remaining drm_debug_printer users over to drm_dbg_printer, as it can handle the cases without struct drm_device pointer, and also provides drm debug category and prefix support. Remove drm_debug_printer altogether. Signed-off-by: Jani Nikula Reviewed-by: Luca Coelho Acked-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/18b5b91e62d071675a651f6f91c58f05ad74134a.1705410327.git.jani.nikula@intel.com

drm/print: add drm_dbg_printer() for drm device specific printer

2024-02-09T09:51:53+00:00

We've lacked a device specific debug printer. Add one. Take category into account too. __builtin_return_address(0) is inaccurate here, so don't use it. If necessary, we can later pass __func__ to drm_dbg_printer() by wrapping it inside a macro. Signed-off-by: Jani Nikula Reviewed-by: Luca Coelho Acked-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/48607d58e5cdf8341ffdd522257542fa2ce41a19.1705410327.git.jani.nikula@intel.com

drm/print: make drm_err_printer() device specific by using drm_err()

2024-02-09T09:51:13+00:00

With few users for drm_err_printer(), it's still feasible to convert it to be device specific. Use drm_err() under the hood. While at it, make the prefix optional. Signed-off-by: Jani Nikula Reviewed-by: Luca Coelho Acked-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/2a9cdcfc1df44568078f7c131e2e7e0f7c94e97e.1705410327.git.jani.nikula@intel.com

drm_print: add _ddebug descriptor to drm_*dbg prototypes

2022-09-24T13:02:02+00:00

upgrade the callchain to drm_dbg() and drm_dev_dbg(); add a struct _ddebug ptr parameter to them, and supply that additional param by replacing the '_no_desc' flavor of dyndbg Factory macro currently used with the flavor that supplies the descriptor. NOTES: The descriptor gives these fns access to the decorator flags, but they do none of the dynamic-prefixing done by dynamic_emit_prefix(), which is currently static. DRM already has conventions for logging/messaging; just tossing optional decorations on top probably wouldn't help. Instead, existing flags (or new ones, perhaps 'sd' ala lspci) can be used to make current message conventions optional. This suggests a new drmdbg_prefix_emit() to handle prefixing locally. For CONFIG_DRM_USE_DYNAMIC_DEBUG=N, just pass null descriptor. desc->class_id is redundant with category parameter, but its availability is dependent on desc. Signed-off-by: Jim Cromie Link: https://lore.kernel.org/r/20220912052852.1123868-10-jim.cromie@gmail.com Signed-off-by: Greg Kroah-Hartman

drm_print: prefer bare printk KERN_DEBUG on generic fn

2022-09-24T13:02:02+00:00

drm_print.c calls pr_debug() just once, from __drm_printfn_debug(), which is a generic/service fn. The callsite is compile-time enabled by DEBUG in both DYNAMIC_DEBUG=y/n builds. For dyndbg builds, reverting this callsite back to bare printk is correcting a few anti-features: 1- callsite is generic, serves multiple drm users. it is soft-wired on currently by #define DEBUG could accidentally: #> echo -p > /proc/dynamic_debug/control 2- optional "decorations" by dyndbg are unhelpful/misleading here, they describe only the generic site, not end users IOW, 1,2 are unhelpful at best, and possibly confusing. reverting yields a nominal data and text shrink: text data bss dec hex filename 462583 36604 54592 553779 87333 /kernel/drivers/gpu/drm/drm.ko 462515 36532 54592 553639 872a7 -dirty/kernel/drivers/gpu/drm/drm.ko Signed-off-by: Jim Cromie Link: https://lore.kernel.org/r/20220912052852.1123868-9-jim.cromie@gmail.com Signed-off-by: Greg Kroah-Hartman

drm_print: optimize drm_debug_enabled for jump-label

2022-09-24T13:02:02+00:00

When CONFIG_DRM_USE_DYNAMIC_DEBUG=y, the drm.debug API (a macro stack, calling _+drm_*dbg() eventually) invokes a dyndbg Factory macro to create a descriptor for each callsite, thus making them individually >control-able. In this case, the calls to _drm_*dbg are unreachable unless the callsite is enabled. So those calls can short-circuit their early do-nothing returns. Provide and use __drm_debug_enabled(), to do this when config'd, or the _raw flags-check otherwize. And since dyndbg is in use, lets also instrument the remaining users of drm_debug_enabled, by wrapping the _raw in a macro with a: pr_debug("todo: is this frequent enough to optimize ?\n"); For CONFIG_DRM_USE_DYNAMIC_DEBUG=n, do no site instrumenting at all, since JUMP_LABEL might be off, and we don't want to make work. With drm, amdgpu, i915, nouveau loaded, heres remaining uses of drm_debug_enabled(), which costs ~1.5kb data to control the pr_debug("todo:..")s. Some of those uses might be ok to use __drm_debug_enabled() by inspection, others might warrant conversion to use dyndbg Factory macros, and that would want callrate data to estimate the savings possible. TBH, any remaining savings are probably small; drm.debug covers the vast bulk of the uses. Maybe "vblank" is the exception. :#> grep todo /proc/dynamic_debug/control | wc 21 168 2357 :#> grep todo /proc/dynamic_debug/control drivers/gpu/drm/drm_edid_load.c:178 [drm]edid_load =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/drm_vblank.c:410 [drm]drm_crtc_accurate_vblank_count =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/drm_vblank.c:787 [drm]drm_crtc_vblank_helper_get_vblank_timestamp_internal =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/drm_vblank.c:1491 [drm]drm_vblank_restore =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/drm_vblank.c:1433 [drm]drm_vblank_enable =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/drm_plane.c:2168 [drm]drm_mode_setplane =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/display/drm_dp_mst_topology.c:1359 [drm_display_helper]drm_dp_mst_wait_tx_reply =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/display/drm_dp_mst_topology.c:2864 [drm_display_helper]process_single_tx_qlock =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/display/drm_dp_mst_topology.c:2909 [drm_display_helper]drm_dp_queue_down_tx =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/display/drm_dp_mst_topology.c:1686 [drm_display_helper]drm_dp_mst_update_slots =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/i915/display/intel_dp.c:1111 [i915]intel_dp_print_rates =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/i915/display/intel_backlight.c:5434 [i915]cnp_enable_backlight =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/i915/display/intel_backlight.c:5459 [i915]intel_backlight_device_register =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/i915/display/intel_opregion.c:43 [i915]intel_opregion_notify_encoder =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/i915/display/intel_opregion.c:53 [i915]asle_set_backlight =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/i915/display/intel_bios.c:1088 [i915]intel_bios_is_dsi_present =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/i915/display/intel_display_debugfs.c:6153 [i915]i915_drrs_ctl_set =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/i915/intel_pcode.c:26 [i915]snb_pcode_read =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/i915/i915_getparam.c:785 [i915]i915_getparam_ioctl =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/amd/amdgpu/vcn_v2_5.c:282 [amdgpu]vcn_v2_5_process_interrupt =_ "todo: maybe avoid via dyndbg\n" drivers/gpu/drm/amd/amdgpu/vcn_v2_0.c:433 [amdgpu]vcn_v2_0_process_interrupt =_ "todo: maybe avoid via dyndbg\n" :#> Signed-off-by: Jim Cromie Link: https://lore.kernel.org/r/20220912052852.1123868-8-jim.cromie@gmail.com Signed-off-by: Greg Kroah-Hartman

drm_print: interpose drm_*dbg with forwarding macros

2022-09-24T13:02:01+00:00

change drm_dev_dbg & drm_dbg to macros, which forward to the renamed functions (with __ prefix added). Those functions sit below the categorized layer of macros implementing the DRM debug.category API, and implement most of it. These are good places to insert dynamic-debug jump-label mechanics, which will allow DRM to avoid the runtime cost of drm_debug_enabled(). no functional changes. memory cost baseline: (unchanged) bash-5.1# drms_load [ 9.220389] dyndbg: 1 debug prints in module drm [ 9.224426] ACPI: bus type drm_connector registered [ 9.302192] dyndbg: 2 debug prints in module ttm [ 9.305033] dyndbg: 8 debug prints in module video [ 9.627563] dyndbg: 127 debug prints in module i915 [ 9.721505] AMD-Vi: AMD IOMMUv2 functionality not available on this system - This is not a bug. [ 10.091345] dyndbg: 2196 debug prints in module amdgpu [ 10.106589] [drm] amdgpu kernel modesetting enabled. [ 10.107270] amdgpu: CRAT table not found [ 10.107926] amdgpu: Virtual CRAT table created for CPU [ 10.108398] amdgpu: Topology: Add CPU node [ 10.168507] dyndbg: 3 debug prints in module wmi [ 10.329587] dyndbg: 3 debug prints in module nouveau Signed-off-by: Jim Cromie Link: https://lore.kernel.org/r/20220912052852.1123868-4-jim.cromie@gmail.com Signed-off-by: Greg Kroah-Hartman

drm: POC drm on dyndbg - use in core, 2 helpers, 3 drivers.

2022-09-24T13:02:01+00:00

Use DECLARE_DYNDBG_CLASSMAP across DRM: - in .c files, since macro defines/initializes a record - in drivers, $mod_{drv,drm,param}.c ie where param setup is done, since a classmap is param related - in drm/drm_print.c since existing __drm_debug param is defined there, and we ifdef it, and provide an elaborated alternative. - in drm_*_helper modules: dp/drm_dp - 1st item in makefile target drivers/gpu/drm/drm_crtc_helper.c - random pick iirc. Since these modules all use identical CLASSMAP declarations (ie: names and .class_id's) they will all respond together to "class DRM_UT_*" query-commands: :#> echo class DRM_UT_KMS +p > /proc/dynamic_debug/control NOTES: This changes __drm_debug from int to ulong, so BIT() is usable on it. DRM's enum drm_debug_category values need to sync with the index of their respective class-names here. Then .class_id == category, and dyndbg's class FOO mechanisms will enable drm_dbg(DRM_UT_KMS, ...). Though DRM needs consistent categories across all modules, thats not generally needed; modules X and Y could define FOO differently (ie a different NAME => class_id mapping), changes are made according to each module's private class-map. No callsites are actually selected by this patch, since none are class'd yet. Signed-off-by: Jim Cromie Link: https://lore.kernel.org/r/20220912052852.1123868-3-jim.cromie@gmail.com Signed-off-by: Greg Kroah-Hartman

isystem: ship and use stdarg.h

2021-08-19T00:02:55+00:00

Ship minimal stdarg.h (1 type, 4 macros) as . stdarg.h is the only userspace header commonly used in the kernel. GPL 2 version of can be extracted from http://archive.debian.org/debian/pool/main/g/gcc-4.2/gcc-4.2_4.2.4.orig.tar.gz Signed-off-by: Alexey Dobriyan Acked-by: Rafael J. Wysocki Acked-by: Ard Biesheuvel Signed-off-by: Masahiro Yamada

drm/print: convert debug category macros into an enum

2019-11-14T12:08:57+00:00

Mostly for improved documentation, convert the debug category macros into an enum. Drop unused DRM_UT_NONE. Document previously undocumented categories. Reviewed-by: Joonas Lahtinen Acked-by: Ville Syrjälä Acked-by: Sean Paul Signed-off-by: Jani Nikula Link: https://patchwork.freedesktop.org/patch/msgid/96582479e7829d92b89adb805f829e23043ca85c.1572258936.git.jani.nikula@intel.com