[PATCH v2] dm vdo: use a short static string for thread name prefix

[Matthew Sakai]

Also remove MODULE_NAME and a BUG_ON check, both unneeded.

This fixes a warning about string truncation in snprintf that
will never happen in practice:

drivers/md/dm-vdo/vdo.c: In function ‘vdo_make’:
drivers/md/dm-vdo/vdo.c:564:5: error: ‘%s’ directive output may be truncated 
writing up to 55 bytes into a region of size 16 [-Werror=format-truncation=]
    "%s%u", MODULE_NAME, instance);
     ^~
drivers/md/dm-vdo/vdo.c:563:2: note: ‘snprintf’ output between 2 and 66 bytes 
into a destination of size 16
  snprintf(vdo->thread_name_prefix, sizeof(vdo->thread_name_prefix),
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    "%s%u", MODULE_NAME, instance);
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Reported-by: John Garry <john.g.ga...@oracle.com>
Signed-off-by: Matthew Sakai <msa...@redhat.com>
---
 drivers/md/dm-vdo/vdo.c | 9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/drivers/md/dm-vdo/vdo.c b/drivers/md/dm-vdo/vdo.c
index a7e32baab4af..eb4a9e2442dc 100644
--- a/drivers/md/dm-vdo/vdo.c
+++ b/drivers/md/dm-vdo/vdo.c
@@ -142,12 +142,6 @@ static void finish_vdo_request_queue(void *ptr)
        vdo_unregister_allocating_thread();
 }
 
-#ifdef MODULE
-#define MODULE_NAME THIS_MODULE->name
-#else
-#define MODULE_NAME "dm-vdo"
-#endif  /* MODULE */
-
 static const struct vdo_work_queue_type default_queue_type = {
        .start = start_vdo_request_queue,
        .finish = finish_vdo_request_queue,
@@ -559,8 +553,7 @@ int vdo_make(unsigned int instance, struct device_config 
*config, char **reason,
        *vdo_ptr = vdo;
 
        snprintf(vdo->thread_name_prefix, sizeof(vdo->thread_name_prefix),
-                "%s%u", MODULE_NAME, instance);
-       BUG_ON(vdo->thread_name_prefix[0] == '\0');
+                "%s%u", "vdo", instance);
        result = vdo_allocate(vdo->thread_config.thread_count,
                              struct vdo_thread, __func__, &vdo->threads);
        if (result != VDO_SUCCESS) {
-- 
2.45.2