fbarray: reduce duplication in element finding

Just code move to put all checks and calls in one place.

Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>

diff --git a/lib/librte_eal/common/eal_common_fbarray.c b/lib/librte_eal/common/eal_common_fbarray.c
index c5ee017..2237039 100644 (file)
--- a/lib/librte_eal/common/eal_common_fbarray.c
+++ b/lib/librte_eal/common/eal_common_fbarray.c
@@ -675,8 +675,8 @@ rte_fbarray_is_used(struct rte_fbarray *arr, unsigned int idx)
        return ret;
 }
 
-int __rte_experimental
-rte_fbarray_find_next_free(struct rte_fbarray *arr, unsigned int start)
+static int
+fbarray_find(struct rte_fbarray *arr, unsigned int start, bool used)
 {
        int ret = -1;
 
@@ -688,39 +688,43 @@ rte_fbarray_find_next_free(struct rte_fbarray *arr, unsigned int start)
        /* prevent array from changing under us */
        rte_rwlock_read_lock(&arr->rwlock);
 
-       if (arr->len == arr->count) {
-               rte_errno = ENOSPC;
-               goto out;
+       /* cheap checks to prevent doing useless work */
+       if (!used) {
+               if (arr->len == arr->count) {
+                       rte_errno = ENOSPC;
+                       goto out;
+               }
+               if (arr->count == 0) {
+                       ret = start;
+                       goto out;
+               }
+       } else {
+               if (arr->count == 0) {
+                       rte_errno = ENOENT;
+                       goto out;
+               }
+               if (arr->len == arr->count) {
+                       ret = start;
+                       goto out;
+               }
        }
 
-       ret = find_next(arr, start, false);
+       ret = find_next(arr, start, used);
 out:
        rte_rwlock_read_unlock(&arr->rwlock);
        return ret;
 }
 
 int __rte_experimental
-rte_fbarray_find_next_used(struct rte_fbarray *arr, unsigned int start)
+rte_fbarray_find_next_free(struct rte_fbarray *arr, unsigned int start)
 {
-       int ret = -1;
-
-       if (arr == NULL || start >= arr->len) {
-               rte_errno = EINVAL;
-               return -1;
-       }
-
-       /* prevent array from changing under us */
-       rte_rwlock_read_lock(&arr->rwlock);
-
-       if (arr->count == 0) {
-               rte_errno = ENOENT;
-               goto out;
-       }
+       return fbarray_find(arr, start, false);
+}
 
-       ret = find_next(arr, start, true);
-out:
-       rte_rwlock_read_unlock(&arr->rwlock);
-       return ret;
+int __rte_experimental
+rte_fbarray_find_next_used(struct rte_fbarray *arr, unsigned int start)
+{
+       return fbarray_find(arr, start, true);
 }
 
 static int