[PATCH v6 56/57] dyndbg: work ddebug_map_site

From: Jim Cromie
Date: Sun Sep 04 2022 - 17:46:56 EST


attempt container-of, broken, missing use of uplink... took that out.

ptr computations are naive, and wrong.

Deeper prob is lack of _ddebug_vec, with header and descs in same struct.
maybe.

builtin_state looks right in debugger
---
lib/dynamic_debug.c | 21 +++++++++++++++++++--
1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 194367bc13fb..11fea1f818a7 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -173,8 +173,25 @@ static struct ddebug_class_map *ddebug_find_valid_class(struct ddebug_table cons
return NULL;
}

-static inline struct _ddebug_site * _ddebug_map_site(const struct _ddebug *desc)
+/*
+ * mapping from desc to site is multi-step:
+ * - _index back to &descs[0]
+ * - container-of to get header struct above
+ * - ._uplink field, pointing to _ddebug_info (for builtins, loadables)
+ * - di->sites[desc->_map]
+ */
+static struct _ddebug_site * _ddebug_map_site(const struct _ddebug *desc)
{
+ struct _ddebug_info *di;
+ struct _ddebug const *d0 = desc - desc->_index * sizeof(struct _ddebug);
+
+ di = (struct _ddebug_info *) d0;
+
+ v3pr_info("map_site idx:%d map:%d %s.%s di:%px site:%px ds:%px\n",
+ desc->_index, desc->_map,
+ desc->site->_modname, desc->site->_function,
+ di, desc->site, &di->sites[desc->_map]);
+
return desc->site;
}
#define _desc_field(desc, _fld) (desc ? (_ddebug_map_site(desc)->_fld) : "_na_")
@@ -866,7 +883,7 @@ static char *__dynamic_emit_prefix(const struct _ddebug *desc, char *buf)
return buf;
}

-static inline char *dynamic_emit_prefix(struct _ddebug *desc, char *buf)
+char *dynamic_emit_prefix(struct _ddebug *desc, char *buf)
{
if (unlikely(desc->flags & _DPRINTK_FLAGS_INCL_ANY))
return __dynamic_emit_prefix(desc, buf);
--
2.37.2