dyndbg: refine debug verbosity; 1 is basic, 2 more chatty

The verbose/debug logging done for `cat $MNT/dynamic_debug/control` is
voluminous (2 per control file entry + 2 per PAGE).  Moreover, it just
prints pointer and sequence, which is not useful to a dyndbg user.
So just drop them.

Also require verbose>=2 for several other debug printks that are a bit
too chatty for typical needs;

ddebug_change() prints changes, once per modified callsite.  Since
queries like "+p" will enable ~2300 callsites in a typical laptop, a
user probably doesn't need to see them often.  ddebug_exec_queries()
still summarizes with verbose=1.

ddebug_(add|remove)_module() also print 1 line per action on a module,
not needed by typical modprobe user.

This leaves verbose=1 better focussed on the >control parsing process.

Acked-by: <jbaron@akamai.com>
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Link: https://lore.kernel.org/r/20200719231058.1586423-5-jim.cromie@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 2989a590ce9af4331cfb409e23d95bed1ef254ea..c97872cffc8e125a63cc4c5f2363b4806d5f7bef 100644 (file)
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -105,12 +105,15 @@ static char *ddebug_describe_flags(struct _ddebug *dp, char *buf,
        return buf;
 }
 
-#define vpr_info(fmt, ...)                                     \
+#define vnpr_info(lvl, fmt, ...)                               \
 do {                                                           \
-       if (verbose)                                            \
+       if (verbose >= lvl)                                     \
                pr_info(fmt, ##__VA_ARGS__);                    \
 } while (0)
 
+#define vpr_info(fmt, ...)     vnpr_info(1, fmt, ##__VA_ARGS__)
+#define v2pr_info(fmt, ...)    vnpr_info(2, fmt, ##__VA_ARGS__)
+
 static void vpr_info_dq(const struct ddebug_query *query, const char *msg)
 {
        /* trim any trailing newlines */
@@ -198,7 +201,7 @@ static int ddebug_change(const struct ddebug_query *query,
                                static_branch_enable(&dp->key.dd_key_true);
 #endif
                        dp->flags = newflags;
-                       vpr_info("changed %s:%d [%s]%s =%s\n",
+                       v2pr_info("changed %s:%d [%s]%s =%s\n",
                                 trim_prefix(dp->filename), dp->lineno,
                                 dt->mod_name, dp->function,
                                 ddebug_describe_flags(dp, flagbuf,
@@ -771,8 +774,6 @@ static void *ddebug_proc_start(struct seq_file *m, loff_t *pos)
        struct _ddebug *dp;
        int n = *pos;
 
-       vpr_info("called m=%p *pos=%lld\n", m, (unsigned long long)*pos);
-
        mutex_lock(&ddebug_lock);
 
        if (!n)
@@ -795,9 +796,6 @@ static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos)
        struct ddebug_iter *iter = m->private;
        struct _ddebug *dp;
 
-       vpr_info("called m=%p p=%p *pos=%lld\n",
-                m, p, (unsigned long long)*pos);
-
        if (p == SEQ_START_TOKEN)
                dp = ddebug_iter_first(iter);
        else
@@ -818,8 +816,6 @@ static int ddebug_proc_show(struct seq_file *m, void *p)
        struct _ddebug *dp = p;
        char flagsbuf[10];
 
-       vpr_info("called m=%p p=%p\n", m, p);
-
        if (p == SEQ_START_TOKEN) {
                seq_puts(m,
                         "# filename:lineno [module]function flags format\n");
@@ -842,7 +838,6 @@ static int ddebug_proc_show(struct seq_file *m, void *p)
  */
 static void ddebug_proc_stop(struct seq_file *m, void *p)
 {
-       vpr_info("called m=%p p=%p\n", m, p);
        mutex_unlock(&ddebug_lock);
 }
 
@@ -905,7 +900,7 @@ int ddebug_add_module(struct _ddebug *tab, unsigned int n,
        list_add_tail(&dt->link, &ddebug_tables);
        mutex_unlock(&ddebug_lock);
 
-       vpr_info("%u debug prints in module %s\n", n, dt->mod_name);
+       v2pr_info("%u debug prints in module %s\n", n, dt->mod_name);
        return 0;
 }
 
@@ -964,7 +959,7 @@ int ddebug_remove_module(const char *mod_name)
        struct ddebug_table *dt, *nextdt;
        int ret = -ENOENT;
 
-       vpr_info("removing module \"%s\"\n", mod_name);
+       v2pr_info("removing module \"%s\"\n", mod_name);
 
        mutex_lock(&ddebug_lock);
        list_for_each_entry_safe(dt, nextdt, &ddebug_tables, link) {