Use explict atomic for older compilers

diff --git a/lib/dns/rbtdb.c b/lib/dns/rbtdb.c
index 864a159097aa675002bf6b203794575fe1dd1e94..7793be859ee3676657e4d2006821ed1477cbde7a 100644 (file)
--- a/lib/dns/rbtdb.c
+++ b/lib/dns/rbtdb.c
@@ -486,7 +486,7 @@ struct dns_rbtdb {
         * When performing LRU cleaning limit cleaning to headers that were
         * last used at or before this.
         */
-       _Atomic(isc_stdtime_t) last_used;
+       atomic_uint last_used;
 
        /*%
         * Temporary storage for stale cache nodes and dynamically deleted
@@ -6540,7 +6540,8 @@ find_header:
                        if (IS_CACHE(rbtdb)) {
                                if (ZEROTTL(newheader)) {
                                        newheader->last_used =
-                                               rbtdb->last_used + 1;
+                                               atomic_load(&rbtdb->last_used) +
+                                               1;
                                        ISC_LIST_APPEND(rbtdb->rdatasets[idx],
                                                        newheader, link);
                                } else {
@@ -6583,7 +6584,8 @@ find_header:
                                isc_heap_insert(rbtdb->heaps[idx], newheader);
                                if (ZEROTTL(newheader)) {
                                        newheader->last_used =
-                                               rbtdb->last_used + 1;
+                                               atomic_load(&rbtdb->last_used) +
+                                               1;
                                        ISC_LIST_APPEND(rbtdb->rdatasets[idx],
                                                        newheader, link);
                                } else {
@@ -10166,7 +10168,8 @@ expire_lru_headers(dns_rbtdb_t *rbtdb, unsigned int locknum, size_t purgesize,
        size_t purged = 0;
 
        for (header = ISC_LIST_TAIL(rbtdb->rdatasets[locknum]);
-            header != NULL && header->last_used <= rbtdb->last_used &&
+            header != NULL &&
+            header->last_used <= atomic_load(&rbtdb->last_used) &&
             purged <= purgesize;
             header = header_prev)
        {
@@ -10199,7 +10202,8 @@ expire_lru_headers(dns_rbtdb_t *rbtdb, unsigned int locknum, size_t purgesize,
 static void
 overmem_purge(dns_rbtdb_t *rbtdb, rdatasetheader_t *newheader,
              bool tree_locked) {
-       uint32_t locknum_start = rbtdb->lru_sweep++ % rbtdb->node_lock_count;
+       uint32_t locknum_start = atomic_fetch_add(&rbtdb->lru_sweep, 1) %
+                                rbtdb->node_lock_count;
        uint32_t locknum = locknum_start;
        /* Size of added data, possible node and possible ENT node. */
        size_t purgesize = rdataset_size(newheader) +
@@ -10238,7 +10242,7 @@ again:
         */
        if (purged < purgesize) {
                if (min_last_used != 0) {
-                       rbtdb->last_used = min_last_used;
+                       atomic_store(&rbtdb->last_used, min_last_used);
                        if (max_passes-- > 0) {
                                goto again;
                        }