[Intel-gfx] [PATCH v6 31/57] nouveau: change nvkm_debug/trace to use dev_dbg POC

Jim Cromie
2022-09-04T21:48:10Z

These 2 macros formerly used dev_info, and they still check
subdev->debug to gate the printing. So dyndbg control is redundant
ATM (and possibly confusing, since its off by default).

prdbg count is up from 3, or from 65 (with VMM_DEBUG here)

[ 7.765379] dyndbg: 516 debug prints in module nouveau

Its possible to control error, warn, info callsites too, but they're
usually on, and the .data overheads on ~450 more callsites (56 bytes
each) would just be wasted.

$ for l in fatal error warn info debug trace spam; do
echo $l; ack nvkm_$l drivers/gpu |wc; done
fatal
3 19 335
error
289 1956 30651
warn
84 513 8860
info
14 88 1502
debug
387 2339 40844
trace
31 219 3368
spam
1 7 123

bash-5.1# echo $(( 516-65-387-31-1 ))
32

Thats approximate; not accounting #defines and doc/comment mentions.

NOTE: this patch changes the log-level of the macro-issued messages
from KERN_INFO to KERN_DEBUG. Adding a .kern_lvl field to struct
_ddebug could fix that.

RFC: dyndbg & subdev->debug

Separate class-maps for each subdev are possible; except for the
coordinated use of _base, each is independent, including choice of
DISJOINT or LEVELS, as long as class-names don't conflict.
So theres some flexibility.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
---
drivers/gpu/drm/nouveau/include/nvkm/core/subdev.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/include/nvkm/core/subdev.h b/drivers/gpu/drm/nouveau/include/nvkm/core/subdev.h
index 96113c8bee8c..065d07ccea87 100644
--- a/drivers/gpu/drm/nouveau/include/nvkm/core/subdev.h
+++ b/drivers/gpu/drm/nouveau/include/nvkm/core/subdev.h
@@ -59,8 +59,8 @@ void nvkm_subdev_intr(struct nvkm_subdev *);
#define nvkm_error(s,f,a...) nvkm_printk((s), ERROR, err, f, ##a)
#define nvkm_warn(s,f,a...) nvkm_printk((s), WARN, notice, f, ##a)
#define nvkm_info(s,f,a...) nvkm_printk((s), INFO, info, f, ##a)
-#define nvkm_debug(s,f,a...) nvkm_printk((s), DEBUG, info, f, ##a)
-#define nvkm_trace(s,f,a...) nvkm_printk((s), TRACE, info, f, ##a)
+#define nvkm_debug(s,f,a...) nvkm_printk((s), DEBUG, dbg, f, ##a)
+#define nvkm_trace(s,f,a...) nvkm_printk((s), TRACE, dbg, f, ##a)
#define nvkm_spam(s,f,a...) nvkm_printk((s), SPAM, dbg, f, ##a)

#define nvkm_error_ratelimited(s,f,a...) nvkm_printk((s), ERROR, err_ratelimited, f, ##a)
--
2.37.2