1 files changed, 28 insertions, 13 deletions

diff --git a/util/qht.c b/util/qht.c
index 55b0738cd1..c138777a9c 100644
--- a/util/qht.c
+++ b/util/qht.c
@@ -351,11 +351,14 @@ static struct qht_map *qht_map_create(size_t n_buckets)
     return map;
 }
 
-void qht_init(struct qht *ht, size_t n_elems, unsigned int mode)
+void qht_init(struct qht *ht, qht_cmp_func_t cmp, size_t n_elems,
+              unsigned int mode)
 {
     struct qht_map *map;
     size_t n_buckets = qht_elems_to_buckets(n_elems);
 
+    g_assert(cmp);
+    ht->cmp = cmp;
     ht->mode = mode;
     qemu_mutex_init(&ht->lock);
     map = qht_map_create(n_buckets);
@@ -479,8 +482,8 @@ void *qht_lookup__slowpath(struct qht_bucket *b, qht_lookup_func_t func,
     return ret;
 }
 
-void *qht_lookup(struct qht *ht, qht_lookup_func_t func, const void *userp,
-                 uint32_t hash)
+void *qht_lookup_custom(struct qht *ht, const void *userp, uint32_t hash,
+                        qht_lookup_func_t func)
 {
     struct qht_bucket *b;
     struct qht_map *map;
@@ -502,10 +505,15 @@ void *qht_lookup(struct qht *ht, qht_lookup_func_t func, const void *userp,
     return qht_lookup__slowpath(b, func, userp, hash);
 }
 
+void *qht_lookup(struct qht *ht, const void *userp, uint32_t hash)
+{
+    return qht_lookup_custom(ht, userp, hash, ht->cmp);
+}
+
 /* call with head->lock held */
-static bool qht_insert__locked(struct qht *ht, struct qht_map *map,
-                               struct qht_bucket *head, void *p, uint32_t hash,
-                               bool *needs_resize)
+static void *qht_insert__locked(struct qht *ht, struct qht_map *map,
+                                struct qht_bucket *head, void *p, uint32_t hash,
+                                bool *needs_resize)
 {
     struct qht_bucket *b = head;
     struct qht_bucket *prev = NULL;
@@ -515,8 +523,9 @@ static bool qht_insert__locked(struct qht *ht, struct qht_map *map,
     do {
         for (i = 0; i < QHT_BUCKET_ENTRIES; i++) {
             if (b->pointers[i]) {
-                if (unlikely(b->pointers[i] == p)) {
-                    return false;
+                if (unlikely(b->hashes[i] == hash &&
+                             ht->cmp(b->pointers[i], p))) {
+                    return b->pointers[i];
                 }
             } else {
                 goto found;
@@ -545,7 +554,7 @@ static bool qht_insert__locked(struct qht *ht, struct qht_map *map,
     atomic_set(&b->hashes[i], hash);
     atomic_set(&b->pointers[i], p);
     seqlock_write_end(&head->sequence);
-    return true;
+    return NULL;
 }
 
 static __attribute__((noinline)) void qht_grow_maybe(struct qht *ht)
@@ -569,25 +578,31 @@ static __attribute__((noinline)) void qht_grow_maybe(struct qht *ht)
     qemu_mutex_unlock(&ht->lock);
 }
 
-bool qht_insert(struct qht *ht, void *p, uint32_t hash)
+bool qht_insert(struct qht *ht, void *p, uint32_t hash, void **existing)
 {
     struct qht_bucket *b;
     struct qht_map *map;
     bool needs_resize = false;
-    bool ret;
+    void *prev;
 
     /* NULL pointers are not supported */
     qht_debug_assert(p);
 
     b = qht_bucket_lock__no_stale(ht, hash, &map);
-    ret = qht_insert__locked(ht, map, b, p, hash, &needs_resize);
+    prev = qht_insert__locked(ht, map, b, p, hash, &needs_resize);
     qht_bucket_debug__locked(b);
     qemu_spin_unlock(&b->lock);
 
     if (unlikely(needs_resize) && ht->mode & QHT_MODE_AUTO_RESIZE) {
         qht_grow_maybe(ht);
     }
-    return ret;
+    if (likely(prev == NULL)) {
+        return true;
+    }
+    if (existing) {
+        *existing = prev;
+    }
+    return false;
 }
 
 static inline bool qht_entry_is_last(struct qht_bucket *b, int pos)