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authorJason Gunthorpe <jgg@mellanox.com>2018-08-16 13:08:18 -0600
committerJason Gunthorpe <jgg@mellanox.com>2018-08-16 13:12:00 -0600
commit89982f7ccee2fcd8fea7936b81eec6defbf0f131 (patch)
treefc553c8d008d24595ad7de0ea0f3b56f656da27c /lib/refcount.c
parenta1ceeca679dccc492235f0f629d9e9f7b3d51ca8 (diff)
parent94710cac0ef4ee177a63b5227664b38c95bbf703 (diff)
Merge tag 'v4.18' into rdma.git for-next
Resolve merge conflicts from the -rc cycle against the rdma.git tree: Conflicts: drivers/infiniband/core/uverbs_cmd.c - New ifs added to ib_uverbs_ex_create_flow in -rc and for-next - Merge removal of file->ucontext in for-next with new code in -rc drivers/infiniband/core/uverbs_main.c - for-next removed code from ib_uverbs_write() that was modified in for-rc Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Diffstat (limited to 'lib/refcount.c')
-rw-r--r--lib/refcount.c28
1 files changed, 28 insertions, 0 deletions
diff --git a/lib/refcount.c b/lib/refcount.c
index 0eb48353abe3..d3b81cefce91 100644
--- a/lib/refcount.c
+++ b/lib/refcount.c
@@ -350,3 +350,31 @@ bool refcount_dec_and_lock(refcount_t *r, spinlock_t *lock)
}
EXPORT_SYMBOL(refcount_dec_and_lock);
+/**
+ * refcount_dec_and_lock_irqsave - return holding spinlock with disabled
+ * interrupts if able to decrement refcount to 0
+ * @r: the refcount
+ * @lock: the spinlock to be locked
+ * @flags: saved IRQ-flags if the is acquired
+ *
+ * Same as refcount_dec_and_lock() above except that the spinlock is acquired
+ * with disabled interupts.
+ *
+ * Return: true and hold spinlock if able to decrement refcount to 0, false
+ * otherwise
+ */
+bool refcount_dec_and_lock_irqsave(refcount_t *r, spinlock_t *lock,
+ unsigned long *flags)
+{
+ if (refcount_dec_not_one(r))
+ return false;
+
+ spin_lock_irqsave(lock, *flags);
+ if (!refcount_dec_and_test(r)) {
+ spin_unlock_irqrestore(lock, *flags);
+ return false;
+ }
+
+ return true;
+}
+EXPORT_SYMBOL(refcount_dec_and_lock_irqsave);