github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-07-27 09:36:22 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

docs/dyndbg: explain flags parse 1st

Browse Source 
When writing queries to >control, flags are parsed 1st, since they are
the only required field, and they require specific compositions.  So
if the flags draw an error (on those specifics), then keyword errors
aren't reported.  This can be mildly confusing/annoying, so explain it
instead.

cc: linux-doc@vger.kernel.org
Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com>
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20260502-dyndbg-doc-v1-2-67cc4a93a77e@gmail.com>
This commit is contained in:
Jim Cromie 2026-05-02 17:32:56 -06:00 committed by Jonathan Corbet
parent c76934b3f4
commit 5c48ecedf7
1 changed files with 12 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
Documentation/admin-guide/dynamic-debug-howto.rst
View File

@ -109,10 +109,19 @@ The match-spec's select *prdbgs* from the catalog, upon which to apply
the flags-spec, all constraints are ANDed together. An absent keyword
is the same as keyword "*".
Note that since the match-spec can be empty, the flags are checked 1st,
then the pairs of keyword and value. Flag errs will hide keyword errs::
A match specification is a keyword, which selects the attribute of
the callsite to be compared, and a value to compare against. Possible
keywords are:::
bash-5.2# ddcmd mod bar +foo
dyndbg: read 13 bytes from userspace
dyndbg: query 0: "mod bar +foo" mod:*
dyndbg: unknown flag 'o'
dyndbg: flags parse failed
dyndbg: processed 1 queries, with 0 matches, 1 errs
So a match-spec is a keyword, which selects the attribute of the
callsite to be compared, and a value to compare against. Possible
keywords are::
match-spec ::= 'func' string |
'file' string |