dyndbg: add source filename to prefix

Printing the line number without the file is of limited usefulness.

Knowing the filename also makes it also easier to relate the logged
information to the controlfile.

Example:

    # modprobe test_dynamic_debug
    # echo 'file test_dynamic_debug.c =pfsl' > /proc/dynamic_debug/control
    # echo 1 > /sys/module/test_dynamic_debug/parameters/do_prints
    # dmesg | tail -2
    [   71.802212] do_cats:lib/test_dynamic_debug.c:103: test_dd: doing categories
    [   71.802227] do_levels:lib/test_dynamic_debug.c:123: test_dd: doing levels

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: Jason Baron <jbaron@akamai.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20230709-dyndbg-filename-v2-3-fd83beef0925@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/admin-guide/dynamic-debug-howto.rst b/Documentation/admin-guide/dynamic-debug-howto.rst
index 8dc668cc1216e453ed4c5ca7e50f6dd3fdf06d4c..0b3d39c610d9c7dbbcde2894507ea4d399106e6c 100644 (file)
--- a/Documentation/admin-guide/dynamic-debug-howto.rst
+++ b/Documentation/admin-guide/dynamic-debug-howto.rst
@@ -216,13 +216,14 @@ The flags are::
   t    Include thread ID, or <intr>
   m    Include module name
   f    Include the function name
+  s    Include the source file name
   l    Include line number
 
 For ``print_hex_dump_debug()`` and ``print_hex_dump_bytes()``, only
 the ``p`` flag has meaning, other flags are ignored.
 
-Note the regexp ``^[-+=][flmpt_]+$`` matches a flags specification.
-To clear all flags at once, use ``=_`` or ``-flmpt``.
+Note the regexp ``^[-+=][fslmpt_]+$`` matches a flags specification.
+To clear all flags at once, use ``=_`` or ``-fslmpt``.
 
 
 Debug messages during Boot Process

diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h
index 061dd84d09f30625ae41d21720783e03f51bfaef..4fcbf4d4fd0a29d11c550805e0e4dd99aae0ac44 100644 (file)
--- a/include/linux/dynamic_debug.h
+++ b/include/linux/dynamic_debug.h
@@ -37,10 +37,12 @@ struct _ddebug {
 #define _DPRINTK_FLAGS_INCL_FUNCNAME   (1<<2)
 #define _DPRINTK_FLAGS_INCL_LINENO     (1<<3)
 #define _DPRINTK_FLAGS_INCL_TID                (1<<4)
+#define _DPRINTK_FLAGS_INCL_SOURCENAME (1<<5)
 
 #define _DPRINTK_FLAGS_INCL_ANY                \
        (_DPRINTK_FLAGS_INCL_MODNAME | _DPRINTK_FLAGS_INCL_FUNCNAME |\
-        _DPRINTK_FLAGS_INCL_LINENO  | _DPRINTK_FLAGS_INCL_TID)
+        _DPRINTK_FLAGS_INCL_LINENO  | _DPRINTK_FLAGS_INCL_TID |\
+        _DPRINTK_FLAGS_INCL_SOURCENAME)
 
 #if defined DEBUG
 #define _DPRINTK_FLAGS_DEFAULT _DPRINTK_FLAGS_PRINT

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 166229dfe171d2a7b3de6e5d6a689c1eb47bd088..6fba6423cc10b512acdfac38cc44887a626c8096 100644 (file)
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -92,6 +92,7 @@ static const struct { unsigned flag:8; char opt_char; } opt_array[] = {
        { _DPRINTK_FLAGS_PRINT, 'p' },
        { _DPRINTK_FLAGS_INCL_MODNAME, 'm' },
        { _DPRINTK_FLAGS_INCL_FUNCNAME, 'f' },
+       { _DPRINTK_FLAGS_INCL_SOURCENAME, 's' },
        { _DPRINTK_FLAGS_INCL_LINENO, 'l' },
        { _DPRINTK_FLAGS_INCL_TID, 't' },
        { _DPRINTK_FLAGS_NONE, '_' },
@@ -836,6 +837,9 @@ static char *__dynamic_emit_prefix(const struct _ddebug *desc, char *buf)
        if (desc->flags & _DPRINTK_FLAGS_INCL_FUNCNAME)
                pos += snprintf(buf + pos, remaining(pos), "%s:",
                                desc->function);
+       if (desc->flags & _DPRINTK_FLAGS_INCL_SOURCENAME)
+               pos += snprintf(buf + pos, remaining(pos), "%s:",
+                               trim_prefix(desc->filename));
        if (desc->flags & _DPRINTK_FLAGS_INCL_LINENO)
                pos += snprintf(buf + pos, remaining(pos), "%d:",
                                desc->lineno);