[PATCH v8 03/16] dyndbg: rationalize verbosity

Jim Cromie jim.cromie at gmail.com
Wed Sep 15 16:39:44 UTC 2021


change current v*pr_info() calls to fit this new scheme:

-1 module add/remove, callsite counts - a few v2s here now
-2 command ingest, splitting
-3 command parsing - many v1s here now
-4 per-site changes - was v2

2 is new, to isolate a problem where a stress-test script (which feeds
large multi-command strings) would produce short writes, truncating
last command and confusing test results.

4 gets per-callsite "changed:" pr-infos, which are very noisy during
stress tests, and obscure v1-3 messages.

Update docs verbose example to 3 per its comment

Signed-off-by: Jim Cromie <jim.cromie at gmail.com>
---
 .../admin-guide/dynamic-debug-howto.rst       |  2 +-
 lib/dynamic_debug.c                           | 22 ++++++++++---------
 2 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/Documentation/admin-guide/dynamic-debug-howto.rst b/Documentation/admin-guide/dynamic-debug-howto.rst
index b119b8277b3e..ab28d200f016 100644
--- a/Documentation/admin-guide/dynamic-debug-howto.rst
+++ b/Documentation/admin-guide/dynamic-debug-howto.rst
@@ -358,7 +358,7 @@ Examples
   // boot-args example, with newlines and comments for readability
   Kernel command line: ...
     // see whats going on in dyndbg=value processing
-    dynamic_debug.verbose=1
+    dynamic_debug.verbose=3
     // enable pr_debugs in 2 builtins, #cmt is stripped
     dyndbg="module params +p #cmt ; module sys +p"
     // enable pr_debugs in 2 functions in a module loaded later
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index da91ff507117..fd5aca157aec 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -118,6 +118,8 @@ do {								\
 
 #define vpr_info(fmt, ...)	vnpr_info(1, fmt, ##__VA_ARGS__)
 #define v2pr_info(fmt, ...)	vnpr_info(2, fmt, ##__VA_ARGS__)
+#define v3pr_info(fmt, ...)	vnpr_info(3, fmt, ##__VA_ARGS__)
+#define v4pr_info(fmt, ...)	vnpr_info(4, fmt, ##__VA_ARGS__)
 
 static void vpr_info_dq(const struct ddebug_query *query, const char *msg)
 {
@@ -130,7 +132,7 @@ static void vpr_info_dq(const struct ddebug_query *query, const char *msg)
 			fmtlen--;
 	}
 
-	vpr_info("%s: func=\"%s\" file=\"%s\" module=\"%s\" format=\"%.*s\" lineno=%u-%u\n",
+	v3pr_info("%s: func=\"%s\" file=\"%s\" module=\"%s\" format=\"%.*s\" lineno=%u-%u\n",
 		 msg,
 		 query->function ?: "",
 		 query->filename ?: "",
@@ -213,7 +215,7 @@ static int ddebug_change(const struct ddebug_query *query,
 				static_branch_enable(&dp->key.dd_key_true);
 #endif
 			dp->flags = newflags;
-			v2pr_info("changed %s:%d [%s]%s =%s\n",
+			v4pr_info("changed %s:%d [%s]%s =%s\n",
 				 trim_prefix(dp->filename), dp->lineno,
 				 dt->mod_name, dp->function,
 				 ddebug_describe_flags(dp->flags, &fbuf));
@@ -273,7 +275,7 @@ static int ddebug_tokenize(char *buf, char *words[], int maxwords)
 		buf = end;
 	}
 
-	if (verbose) {
+	if (verbose >= 3) {
 		int i;
 		pr_info("split into words:");
 		for (i = 0; i < nwords; i++)
@@ -333,7 +335,7 @@ static int parse_linerange(struct ddebug_query *query, const char *first)
 	} else {
 		query->last_lineno = query->first_lineno;
 	}
-	vpr_info("parsed line %d-%d\n", query->first_lineno,
+	v3pr_info("parsed line %d-%d\n", query->first_lineno,
 		 query->last_lineno);
 	return 0;
 }
@@ -447,7 +449,7 @@ static int ddebug_parse_flags(const char *str, struct flag_settings *modifiers)
 		pr_err("bad flag-op %c, at start of %s\n", *str, str);
 		return -EINVAL;
 	}
-	vpr_info("op='%c'\n", op);
+	v3pr_info("op='%c'\n", op);
 
 	for (; *str ; ++str) {
 		for (i = ARRAY_SIZE(opt_array) - 1; i >= 0; i--) {
@@ -461,7 +463,7 @@ static int ddebug_parse_flags(const char *str, struct flag_settings *modifiers)
 			return -EINVAL;
 		}
 	}
-	vpr_info("flags=0x%x\n", modifiers->flags);
+	v3pr_info("flags=0x%x\n", modifiers->flags);
 
 	/* calculate final flags, mask based upon op */
 	switch (op) {
@@ -477,7 +479,7 @@ static int ddebug_parse_flags(const char *str, struct flag_settings *modifiers)
 		modifiers->flags = 0;
 		break;
 	}
-	vpr_info("*flagsp=0x%x *maskp=0x%x\n", modifiers->flags, modifiers->mask);
+	v3pr_info("*flagsp=0x%x *maskp=0x%x\n", modifiers->flags, modifiers->mask);
 
 	return 0;
 }
@@ -540,7 +542,7 @@ static int ddebug_exec_queries(char *query, const char *modname)
 		}
 		i++;
 	}
-	vpr_info("processed %d queries, with %d matches, %d errs\n",
+	v2pr_info("processed %d queries, with %d matches, %d errs\n",
 		 i, nfound, errs);
 
 	if (exitcode)
@@ -781,7 +783,7 @@ static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf,
 	tmpbuf = memdup_user_nul(ubuf, len);
 	if (IS_ERR(tmpbuf))
 		return PTR_ERR(tmpbuf);
-	vpr_info("read %d bytes from userspace\n", (int)len);
+	v2pr_info("read %u bytes from userspace <\n%s>\n", (unsigned)len, tmpbuf);
 
 	ret = ddebug_exec_queries(tmpbuf, NULL);
 	kfree(tmpbuf);
@@ -969,7 +971,7 @@ int ddebug_add_module(struct _ddebug *tab, unsigned int n,
 	list_add(&dt->link, &ddebug_tables);
 	mutex_unlock(&ddebug_lock);
 
-	v2pr_info("%3u debug prints in module %s\n", n, dt->mod_name);
+	vpr_info("%3u debug prints in module %s\n", n, dt->mod_name);
 	return 0;
 }
 
-- 
2.31.1



More information about the dri-devel mailing list