From 42bd0384d77ef7552954056928018f5cfa91a013 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Javier=20Gonz=C3=A1lez?= <javier@javigon.com>
Date: Tue, 11 Dec 2018 20:16:21 +0100
Subject: [PATCH] lightnvm: pblk: avoid ref warning on cache creation
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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.
Fixes: 1864de94ec9d6 "lightnvm: pblk: stop recreating global caches"
Signed-off-by: Javier González <javier@cnexlabs.com>
Reviewed-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
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 0e37104de5968..72ad3e70318c0 100644
--- a/drivers/lightnvm/pblk-init.c
+++ b/drivers/lightnvm/pblk-init.c
@@ -347,23 +347,19 @@ 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;
}
--
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