[PATCH 3/6] dyndbg: rationalize verbosity

[Jim Cromie]

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

-1 module level activity: add/remove, etc
-2 command ingest, splitting
   per >control write
-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 causing parsing errors, which confused
test results.  The 1st fix was to use syswrite in the script, to
deliver full proper commands.

-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 (potential conflict here)

Signed-off-by: Jim Cromie <jim.cromie@xxxxxxxxx>
---
 .../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 5403a4515a4a..47286a73fff4 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 %zu bytes from userspace <\n%s>\n", 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