dyndbg: use the module notifier callbacks

Bring dynamic debug in line with other subsystems by using the module
notifier callbacks. This results in a net decrease in core module
code.

Additionally, Jim Cromie has a new dynamic debug classmap feature,
which requires that jump labels be initialized prior to dynamic debug.
Specifically, the new feature toggles a jump label from the existing
dynamic_debug_setup() function. However, this does not currently work
properly, because jump labels are initialized via the
'module_notify_list' notifier chain, which is invoked after the
current call to dynamic_debug_setup(). Thus, this patch ensures that
jump labels are initialized prior to dynamic debug by setting the
dynamic debug notifier priority to 0, while jump labels have the
higher priority of 1.

Tested by Jim using his new test case, and I've verfied the correct
printing via: # modprobe test_dynamic_debug dyndbg.

Link: https://lore.kernel.org/lkml/20230113193016.749791-21-jim.cromie@gmail.com/
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/oe-kbuild-all/202302190427.9iIK2NfJ-lkp@intel.com/
Tested-by: Jim Cromie <jim.cromie@gmail.com>
Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
CC: Jim Cromie <jim.cromie@gmail.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jason Baron <jbaron@akamai.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
This commit is contained in:
Jason Baron
2023-03-03 11:50:56 -05:00
committed by Luis Chamberlain
parent 85c37208b0
commit 7deabd6749
5 changed files with 53 additions and 46 deletions

View File

@@ -130,9 +130,6 @@ struct ddebug_class_param {
#if defined(CONFIG_DYNAMIC_DEBUG_CORE)
int ddebug_add_module(struct _ddebug_info *dyndbg, const char *modname);
extern int ddebug_remove_module(const char *mod_name);
extern __printf(2, 3)
void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...);
@@ -304,16 +301,6 @@ int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp);
#include <linux/errno.h>
#include <linux/printk.h>
static inline int ddebug_add_module(struct _ddebug_info *dinfo, const char *modname)
{
return 0;
}
static inline int ddebug_remove_module(const char *mod)
{
return 0;
}
static inline int ddebug_dyndbg_module_param_cb(char *param, char *val,
const char *modname)
{