[PATCH 13/16] dynamic_debug: add modname arg to exec_query callchain

From: jim . cromie
Date: Sun Mar 25 2012 - 19:28:00 EST


From: Jim Cromie <jim.cromie@xxxxxxxxx>

Pass module name into ddebug_exec_queries(), ddebug_exec_query(), and
ddebug_parse_query() as separate parameter. In ddebug_parse_query(),
the module name is added into the query struct before the query-string
is parsed. This allows the query-string to be shorter:

instead of:
$modname.dyndbg="module $modname +fp"
do this:
$modname.dyndbg="+fp"

Omitting "module $modname" from the query string is actually required
for $modname.dyndbg rules; the set-only-once check added in a previous
patch will throw an error if its added again. ddebug_query="..." has
no $modname associated with it, so the query string may include it.

This also fixes redundant "module $modname" otherwise needed to handle
multiple queries per string:

$modname.dyndbg="func foo +fp; func bar +fp"

Signed-off-by: Jim Cromie <jim.cromie@xxxxxxxxx>
---
lib/dynamic_debug.c | 19 ++++++++++++-------
1 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 38bd4d66..7eb7a55 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -338,7 +338,7 @@ static int check_set(const char **dest, char *src, char *name)
* Returns 0 on success, <0 on error.
*/
static int ddebug_parse_query(char *words[], int nwords,
- struct ddebug_query *query)
+ struct ddebug_query *query, const char *modname)
{
unsigned int i;
int rc;
@@ -348,6 +348,10 @@ static int ddebug_parse_query(char *words[], int nwords,
return -EINVAL;
memset(query, 0, sizeof(*query));

+ if (modname)
+ /* support $modname.dyndbg=<multiple queries> */
+ query->module = modname;
+
for (i = 0 ; i < nwords ; i += 2) {
if (!strcmp(words[i], "func"))
rc = check_set(&query->function, words[i+1], "func");
@@ -444,7 +448,7 @@ static int ddebug_parse_flags(const char *str, unsigned int *flagsp,
return 0;
}

-static int ddebug_exec_query(char *query_string)
+static int ddebug_exec_query(char *query_string, const char *modname)
{
unsigned int flags = 0, mask = 0;
struct ddebug_query query;
@@ -455,7 +459,7 @@ static int ddebug_exec_query(char *query_string)
nwords = ddebug_tokenize(query_string, words, MAXWORDS);
if (nwords <= 0)
return -EINVAL;
- if (ddebug_parse_query(words, nwords-1, &query))
+ if (ddebug_parse_query(words, nwords-1, &query, modname))
return -EINVAL;
if (ddebug_parse_flags(words[nwords-1], &flags, &mask))
return -EINVAL;
@@ -471,7 +475,7 @@ static int ddebug_exec_query(char *query_string)
last error or number of matching callsites. Module name is either
in param (for boot arg) or perhaps in query string.
*/
-static int ddebug_exec_queries(char *query)
+static int ddebug_exec_queries(char *query, const char *modname)
{
char *split;
int i, errs = 0, exitcode = 0, rc, nfound = 0;
@@ -487,7 +491,7 @@ static int ddebug_exec_queries(char *query)

vpr_info("query %d: \"%s\"\n", i, query);

- rc = ddebug_exec_query(query);
+ rc = ddebug_exec_query(query, modname);
if (rc < 0) {
errs++;
exitcode = rc;
@@ -652,7 +656,7 @@ static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf,
tmpbuf[len] = '\0';
vpr_info("read %d bytes from userspace\n", (int)len);

- ret = ddebug_exec_queries(tmpbuf);
+ ret = ddebug_exec_queries(tmpbuf, NULL);
kfree(tmpbuf);
if (ret < 0)
return ret;
@@ -878,7 +882,8 @@ static int ddebug_dyndbg_param_cb(char *param, char *val,
if (strcmp(param, "dyndbg"))
return on_err; /* determined by caller */

- ddebug_exec_queries(val ? val : "+p");
+ ddebug_exec_queries((val ? val : "+p"), modname);
+
return 0; /* query failure shouldnt stop module load */
}

--
1.7.7.6

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