[Intel-gfx] [PATCH v6 16/57] dyndbg: add ddebug_attach_module_classes

Jim Cromie
2022-09-04T21:45:06Z

Add ddebug_attach_module_classes(), call it from ddebug_add_module().
It scans the classes/section its given, finds records where the
module-name matches the module being added, and adds them to the
module's maps list. No locking here, since the record
isn't yet linked into the ddebug_tables list.

It is called indirectly from 2 sources:

- from load_module(), where it scans the module's __dyndbg_classes
section, which contains DYNAMIC_DEBUG_CLASSES definitions from just
the module.

- from dynamic_debug_init(), where all DYNAMIC_DEBUG_CLASSES
definitions of each builtin module have been packed together.
This is why ddebug_attach_module_classes() checks module-name.

NOTES

Its (highly) likely that builtin classes will be ordered by module
name (just like prdbg descriptors are in the __dyndbg section). So
the list can be replaced by a vector (ptr + length), which will work
for loaded modules too. This would imitate whats currently done for
the _ddebug descriptors.

That said, converting to vector,len is close to pointless; a small
minority of modules will ever define a class-map, and almost all of
them will have only 1 or 2 class-maps, so theres only a couple dozen
pointers to save. TODO: re-evaluate for lines removable.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
---
v6
. fix compile err due to reorderd commits, and missed lkp report.
. init dt->maps in ddebug_add_module, prior to ddebug_attach_module_classes
---
lib/dynamic_debug.c | 32 +++++++++++++++++++++++++++++++-
1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index fb31a1a2fc3f..b71efd0b491d 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -45,7 +45,7 @@ extern struct ddebug_class_map __start___dyndbg_classes[];
extern struct ddebug_class_map __stop___dyndbg_classes[];

struct ddebug_table {
- struct list_head link;
+ struct list_head link, maps;
const char *mod_name;
unsigned int num_ddebugs;
struct _ddebug *ddebugs;
@@ -921,6 +921,32 @@ static const struct proc_ops proc_fops = {
.proc_write = ddebug_proc_write
};

+static void ddebug_attach_module_classes(struct ddebug_table *dt,
+ struct ddebug_class_map *classes,
+ int num_classes)
+{
+ struct ddebug_class_map *cm;
+ int i, j, ct = 0;
+
+ for (cm = classes, i = 0; i < num_classes; i++, cm++) {
+
+ if (!strcmp(cm->mod_name, dt->mod_name)) {
+
+ v2pr_info("class[%d]: module:%s base:%d len:%d ty:%d\n", i,
+ cm->mod_name, cm->base, cm->length, cm->map_type);
+
+ for (j = 0; j < cm->length; j++)
+ v3pr_info(" %d: %d %s\n", j + cm->base, j,
+ cm->class_names[j]);
+
+ list_add(&cm->link, &dt->maps);
+ ct++;
+ }
+ }
+ if (ct)
+ vpr_info("module:%s attached %d classes\n", dt->mod_name, ct);
+}
+
/*
* Allocate a new ddebug_table for the given module
* and add it to the global list.
@@ -952,6 +978,10 @@ static int __ddebug_add_module(struct _ddebug_info *di, unsigned int base,
dt->num_ddebugs = di->num_descs;

INIT_LIST_HEAD(&dt->link);
+ INIT_LIST_HEAD(&dt->maps);
+
+ if (di->classes && di->num_classes)
+ ddebug_attach_module_classes(dt, di->classes, di->num_classes);

mutex_lock(&ddebug_lock);
list_add_tail(&dt->link, &ddebug_tables);
--
2.37.2