Commit 42bd0384 authored Dec 11, 2018 by Javier González Committed by Jens Axboe Dec 11, 2018

lightnvm: pblk: avoid ref warning on cache creation



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: 1864de94 "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>

parent 85136c01

drivers/lightnvm/pblk-init.c

+5 −9

Original line number	Diff line number	Diff line
		@@ -347,23 +347,19 @@ fail_destroy_ws:

		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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