* [PATCH 2/3] dyndbg: refine export, rename to dynamic_debug_exec_queries()
2020-08-24 18:54 [PATCH 0/3] dynamic-debug fixups for 5.9 Jim Cromie
2020-08-24 18:54 ` [PATCH 1/3] dyndbg: give %3u width in pr-format, cosmetic only Jim Cromie
@ 2020-08-24 18:54 ` Jim Cromie
2020-08-24 19:09 ` Joe Perches
2020-08-24 18:54 ` [PATCH 3/3] dyndbg: fix problem parsing format="foo bar" Jim Cromie
2 siblings, 1 reply; 5+ messages in thread
From: Jim Cromie @ 2020-08-24 18:54 UTC (permalink / raw)
To: jbaron, gregkh, linux-kernel; +Cc: Jim Cromie
commit 59cf47e7df31 dyndbg: export ddebug_exec_queries
left a few configs broken, fix them with ifdef-stubs.
Rename the export to dynamic_debug_exec_queries(). This is a more
canonical function name, instead of exposing the 'ddebug' internal
name prefix. Do this now, before export hits v5.9.0
Implement as new function wrapping ddebug_exec_queries(now static
again), which copies the query-string, preserving ddebug_exec_queries'
in-place parsing, while allowing users to pass "const strings".
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
---
include/linux/dynamic_debug.h | 20 ++++++++++++++++----
lib/dynamic_debug.c | 24 ++++++++++++++++++++++--
2 files changed, 38 insertions(+), 6 deletions(-)
diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h
index aa9ff9e1c0b3..b0191d3aff26 100644
--- a/include/linux/dynamic_debug.h
+++ b/include/linux/dynamic_debug.h
@@ -49,6 +49,10 @@ struct _ddebug {
#if defined(CONFIG_DYNAMIC_DEBUG_CORE)
+
+/* exported for module authors to exercise >control */
+int dynamic_debug_exec_queries(const char *query, const char *modname);
+
int ddebug_add_module(struct _ddebug *tab, unsigned int n,
const char *modname);
extern int ddebug_remove_module(const char *mod_name);
@@ -105,7 +109,7 @@ void __dynamic_ibdev_dbg(struct _ddebug *descriptor,
static_branch_unlikely(&descriptor.key.dd_key_false)
#endif
-#else /* !HAVE_JUMP_LABEL */
+#else /* !CONFIG_JUMP_LABEL */
#define _DPRINTK_KEY_INIT
@@ -117,7 +121,7 @@ void __dynamic_ibdev_dbg(struct _ddebug *descriptor,
unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT)
#endif
-#endif
+#endif /* CONFIG_JUMP_LABEL */
#define __dynamic_func_call(id, fmt, func, ...) do { \
DEFINE_DYNAMIC_DEBUG_METADATA(id, fmt); \
@@ -172,10 +176,11 @@ void __dynamic_ibdev_dbg(struct _ddebug *descriptor,
KERN_DEBUG, prefix_str, prefix_type, \
rowsize, groupsize, buf, len, ascii)
-#else
+#else /* !CONFIG_DYNAMIC_DEBUG_CORE */
#include <linux/string.h>
#include <linux/errno.h>
+#include <linux/printk.h>
static inline int ddebug_add_module(struct _ddebug *tab, unsigned int n,
const char *modname)
@@ -210,6 +215,13 @@ static inline int ddebug_dyndbg_module_param_cb(char *param, char *val,
print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, \
rowsize, groupsize, buf, len, ascii); \
} while (0)
-#endif
+
+static inline int dynamic_debug_exec_queries(const char *query, const char *modname)
+{
+ printk(KERN_WARNING "kernel not built w CONFIG_DYNAMIC_DEBUG_CORE\n");
+ return 0;
+}
+
+#endif /* !CONFIG_DYNAMIC_DEBUG_CORE */
#endif
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 01b7d0210412..b6ab2c643116 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -525,7 +525,7 @@ static int ddebug_exec_query(char *query_string, const char *modname)
last error or number of matching callsites. Module name is either
in param (for boot arg) or perhaps in query string.
*/
-int ddebug_exec_queries(char *query, const char *modname)
+static int ddebug_exec_queries(char *query, const char *modname)
{
char *split;
int i, errs = 0, exitcode = 0, rc, nfound = 0;
@@ -557,7 +557,27 @@ int ddebug_exec_queries(char *query, const char *modname)
return exitcode;
return nfound;
}
-EXPORT_SYMBOL_GPL(ddebug_exec_queries);
+
+/**
+ * dynamic_debug_exec_queries - apply changes to selected dynamic-debug prints
+ * @query: string with callsite-selectors +enablement+decorations
+ * @modname: string containing module name
+ *
+ * This implements the >/proc/dynamic_debug/control reader, allowing
+ * module authors to modify their dynamic-debug callsites. The modname
+ * is canonically struct module.mod_name, but can also be null or a
+ * module-wildcard, for example: "drm*".
+ */
+int dynamic_debug_exec_queries(const char *query, const char *modname)
+{
+ char *qry = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ int rc;
+ strncpy(qry, query, PAGE_SIZE);
+ rc = ddebug_exec_queries(qry, modname);
+ kfree(qry);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(dynamic_debug_exec_queries);
#define PREFIX_SIZE 64
--
2.26.2
^ permalink raw reply [flat|nested] 5+ messages in thread* [PATCH 3/3] dyndbg: fix problem parsing format="foo bar"
2020-08-24 18:54 [PATCH 0/3] dynamic-debug fixups for 5.9 Jim Cromie
2020-08-24 18:54 ` [PATCH 1/3] dyndbg: give %3u width in pr-format, cosmetic only Jim Cromie
2020-08-24 18:54 ` [PATCH 2/3] dyndbg: refine export, rename to dynamic_debug_exec_queries() Jim Cromie
@ 2020-08-24 18:54 ` Jim Cromie
2 siblings, 0 replies; 5+ messages in thread
From: Jim Cromie @ 2020-08-24 18:54 UTC (permalink / raw)
To: jbaron, gregkh, linux-kernel; +Cc: Jim Cromie
14775b049642 dyndbg: accept query terms like file=bar and module=foo
That commit broke on a tokenization modality where a word could start
with a quote, but couldnt continue with one. So the above would
tokenize as 'format="foo' and 'bar"', and fail hard.
This commit fixes the tokenizer by terminating an unquoted token on
the '=', avoiding that problem. And since ddebug-parse-query will
never see a combined 'keyword=value', revert those parts of the
previous commit.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
---
lib/dynamic_debug.c | 33 ++++++++++++++-------------------
1 file changed, 14 insertions(+), 19 deletions(-)
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index b6ab2c643116..4af686e6ef59 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -237,6 +237,7 @@ static int ddebug_tokenize(char *buf, char *words[], int maxwords)
{
int nwords = 0;
+ vpr_info("entry, buf:'%s'\n", buf);
while (*buf) {
char *end;
@@ -247,6 +248,8 @@ static int ddebug_tokenize(char *buf, char *words[], int maxwords)
if (*buf == '#')
break; /* token starts comment, skip rest of line */
+ vpr_info("start-of-word:%d '%s'\n", nwords, buf);
+
/* find `end' of word, whitespace separated or quoted */
if (*buf == '"' || *buf == '\'') {
int quote = *buf++;
@@ -257,7 +260,9 @@ static int ddebug_tokenize(char *buf, char *words[], int maxwords)
return -EINVAL; /* unclosed quote */
}
} else {
- for (end = buf; *end && !isspace(*end); end++)
+ for (end = buf;
+ *end && *end != '=' && !isspace(*end);
+ end++)
;
BUG_ON(end == buf);
}
@@ -373,30 +378,20 @@ static int ddebug_parse_query(char *words[], int nwords,
unsigned int i;
int rc = 0;
char *fline;
- char *keyword, *arg;
+ if (nwords % 2 != 0) {
+ pr_err("expecting pairs of match-spec <value>\n");
+ return -EINVAL;
+ }
if (modname)
/* support $modname.dyndbg=<multiple queries> */
query->module = modname;
- for (i = 0; i < nwords; i++) {
- /* accept keyword=arg */
- vpr_info("%d w:%s\n", i, words[i]);
-
- keyword = words[i];
- arg = strchr(keyword, '=');
- if (arg) {
- *arg++ = '\0';
- } else {
- i++; /* next word is arg */
- if (!(i < nwords)) {
- pr_err("missing arg to keyword: %s\n", keyword);
- return -EINVAL;
- }
- arg = words[i];
- }
- vpr_info("%d key:%s arg:%s\n", i, keyword, arg);
+ for (i = 0; i < nwords; i+=2) {
+ char *keyword = words[i];
+ char *arg = words[i+1];
+ vpr_info("key:'%s' arg:'%s'\n", keyword, arg);
if (!strcmp(keyword, "func")) {
rc = check_set(&query->function, arg, "func");
} else if (!strcmp(keyword, "file")) {
--
2.26.2
^ permalink raw reply [flat|nested] 5+ messages in thread