put pr_debug()s into most functions, to easily see code operate when
module is loaded and used.

  #> dmesg -w &
  #> modprobe kset-example dyndbg=+pfml
  #> cat /sys/kernel/kset-example/*/*
---
 samples/kobject/kset-example.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/samples/kobject/kset-example.c b/samples/kobject/kset-example.c
index c8010f126808..27c9b1beec28 100644
--- a/samples/kobject/kset-example.c
+++ b/samples/kobject/kset-example.c
@@ -56,6 +56,7 @@ static ssize_t foo_attr_show(struct kobject *kobj,
        struct foo_attribute *attribute;
        struct foo_obj *foo;
 
+       pr_debug("called");
        attribute = to_foo_attr(attr);
        foo = to_foo_obj(kobj);
 
@@ -76,6 +77,7 @@ static ssize_t foo_attr_store(struct kobject *kobj,
        struct foo_attribute *attribute;
        struct foo_obj *foo;
 
+       pr_debug("called");
        attribute = to_foo_attr(attr);
        foo = to_foo_obj(kobj);
 
@@ -102,6 +104,7 @@ static void foo_release(struct kobject *kobj)
 {
        struct foo_obj *foo;
 
+       pr_debug("called");
        foo = to_foo_obj(kobj);
        kfree(foo);
 }
@@ -112,6 +115,7 @@ static void foo_release(struct kobject *kobj)
 static ssize_t foo_show(struct foo_obj *foo_obj, struct foo_attribute *attr,
                        char *buf)
 {
+       pr_debug("called");
        return sprintf(buf, "%d\n", foo_obj->foo);
 }
 
@@ -120,6 +124,7 @@ static ssize_t foo_store(struct foo_obj *foo_obj, struct 
foo_attribute *attr,
 {
        int ret;
 
+       pr_debug("called");
        ret = kstrtoint(buf, 10, &foo_obj->foo);
        if (ret < 0)
                return ret;
@@ -140,6 +145,7 @@ static ssize_t b_show(struct foo_obj *foo_obj, struct 
foo_attribute *attr,
 {
        int var;
 
+       pr_debug("called");
        if (strcmp(attr->attr.name, "baz") == 0)
                var = foo_obj->baz;
        else
@@ -152,6 +158,7 @@ static ssize_t b_store(struct foo_obj *foo_obj, struct 
foo_attribute *attr,
 {
        int var, ret;
 
+       pr_debug("called");
        ret = kstrtoint(buf, 10, &var);
        if (ret < 0)
                return ret;
@@ -201,6 +208,7 @@ static struct foo_obj *create_foo_obj(const char *name)
        struct foo_obj *foo;
        int retval;
 
+       pr_debug("called");
        /* allocate the memory for the whole object */
        foo = kzalloc(sizeof(*foo), GFP_KERNEL);
        if (!foo)
@@ -235,11 +243,13 @@ static struct foo_obj *create_foo_obj(const char *name)
 
 static void destroy_foo_obj(struct foo_obj *foo)
 {
+       pr_debug("called");
        kobject_put(&foo->kobj);
 }
 
 static int __init example_init(void)
 {
+       pr_debug("called");
        /*
         * Create a kset with the name of "kset_example",
         * located under /sys/kernel/
@@ -276,6 +286,7 @@ static int __init example_init(void)
 
 static void __exit example_exit(void)
 {
+       pr_debug("called");
        destroy_foo_obj(baz_obj);
        destroy_foo_obj(bar_obj);
        destroy_foo_obj(foo_obj);
-- 
2.26.2

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