eal: report duplicate device event callback

We should return an error value, when the callback is already exist.

Fixes: a753e53d517b ("eal: add device event monitor framework")
Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
Acked-by: David Marchand <david.marchand@redhat.com>

diff --git a/lib/librte_eal/common/eal_common_dev.c b/lib/librte_eal/common/eal_common_dev.c
index d990bfd20dfef07096d146a406686d01580c0cde..8a3bd3100a3b56046535fba19483892622442227 100644 (file)
--- a/lib/librte_eal/common/eal_common_dev.c
+++ b/lib/librte_eal/common/eal_common_dev.c
@@ -480,7 +480,9 @@ rte_dev_event_callback_register(const char *device_name,
                RTE_LOG(ERR, EAL,
                        "The callback is already exist, no need "
                        "to register again.\n");
+               event_cb = NULL;
                ret = -EEXIST;
+               goto error;
        }
 
        rte_spinlock_unlock(&dev_event_lock);