[PATCH v5 00/18] dynamic_debug fixes, cleanups, features, export

From: Jim Cromie
Date: Sun Jul 19 2020 - 19:11:39 EST


this is v5, changes from previous:
- moved a chunk from patch 13 to 12, per Jason
- shorten logging prefix to "dyndbg", drop __func__
- now with more commit-log advocacy
- shuffle EXPORT_GPL(ddebug_exec_queries) last.
- v4+ series Acked-by: jbaron@xxxxxxxxxx

v4: https://lore.kernel.org/lkml/20200620180643.887546-1-jim.cromie@xxxxxxxxx/
v3: https://lore.kernel.org/lkml/20200617162536.611386-1-jim.cromie@xxxxxxxxx/
v2: https://lore.kernel.org/lkml/20200613155738.2249399-1-jim.cromie@xxxxxxxxx/
v1: https://lore.kernel.org/lkml/20200605162645.289174-1-jim.cromie@xxxxxxxxx/


Patchset starts with cleanups;
- change section name from vague "__verbose" to specific "__dyndbg"
- cleaner docs, drop obsolete comment & useless debug prints,
- refine verbose/debug logging
- fix a BUG_ON, ram reporting miscounts. etc..

Then adds query parsing conveniences
- allow "file inode.c:100-200" # combined file & line-range
- allow "file inode.c:start_*" # file & function
- accept "module=foo" query form

internal improvement
- combine flags & mask in a struct, clean 3 func interfaces with it.

make precise format queries easier
- accept "format=^ClassString" anchored query

finally, EXPORT_GPL(ddebug_exec_queries)

This gives module authors complete run-time control over all their
*pr_debug* callsites (when CONFIG_DYNAMIC_DEBUG=y).

Following the drm.debug UI model, drm.debug_chan2 could be wired to a
callback which invokes ddebug_exec_queries to toggle arbitary groups
of pr_debug callsites.

Useful callsite groups would exploit existing message-prefix
classifcation schemes:

"format=^[IF_TRACE]: +p; format=^[SURFACE]: +p" >control


Jim Cromie (18):
dyndbg-docs: eschew file /full/path query in docs
dyndbg-docs: initialization is done early, not arch
dyndbg: drop obsolete comment on ddebug_proc_open
dyndbg: refine debug verbosity; 1 is basic, 2 more chatty
dyndbg: rename __verbose section to __dyndbg
dyndbg: fix overcounting of ram used by dyndbg
dyndbg: fix a BUG_ON in ddebug_describe_flags
dyndbg: fix pr_err with empty string
dyndbg: prefer declarative init in caller, to memset in callee
dyndbg: make ddebug_tables list LIFO for add/remove_module
dyndbg: use gcc ?: to reduce word count
dyndbg: refactor parse_linerange out of ddebug_parse_query
dyndbg: accept 'file foo.c:func1' and 'file foo.c:10-100'
dyndbg: accept query terms like file=bar and module=foo
dyndbg: combine flags & mask into a struct, simplify with it
dyndbg: allow anchored match on format query term
dyndbg: shorten our logging prefix, drop __func__
dyndbg: export ddebug_exec_queries

.../admin-guide/dynamic-debug-howto.rst | 29 +-
include/asm-generic/vmlinux.lds.h | 6 +-
include/linux/dynamic_debug.h | 4 +-
kernel/module.c | 2 +-
lib/dynamic_debug.c | 269 ++++++++++--------
5 files changed, 173 insertions(+), 137 deletions(-)

--
2.26.2