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Subject[PATCH] lightnvm: pblk: avoid ref warning on cache creation
Date
The current kref implementation around pblk global caches triggers a
false positive on refcount_inc_checked() (when called) as the kref is
initialized to 0. Instead of usint kref_inc() on a 0 reference, which is
in principle correct, use kref_init() to avoid the check. This is also
more explicit about what actually happens on cache creation.

In the process, do a small refactoring to use kref helpers.

Signed-off-by: Javier González <javier@cnexlabs.com>
---
drivers/lightnvm/pblk-init.c | 14 +++++---------
1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/drivers/lightnvm/pblk-init.c b/drivers/lightnvm/pblk-init.c
index 13822594647c..e225bd60cbb4 100644
--- a/drivers/lightnvm/pblk-init.c
+++ b/drivers/lightnvm/pblk-init.c
@@ -350,23 +350,19 @@ static int pblk_create_global_caches(void)

static int pblk_get_global_caches(void)
{
- int ret;
+ int ret = 0;

mutex_lock(&pblk_caches.mutex);

- if (kref_read(&pblk_caches.kref) > 0) {
- kref_get(&pblk_caches.kref);
- mutex_unlock(&pblk_caches.mutex);
- return 0;
- }
+ if (kref_get_unless_zero(&pblk_caches.kref))
+ goto out;

ret = pblk_create_global_caches();
-
if (!ret)
- kref_get(&pblk_caches.kref);
+ kref_init(&pblk_caches.kref);

+out:
mutex_unlock(&pblk_caches.mutex);
-
return ret;
}

--
2.7.4
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