Simplify fctx_unlink() and fctx_destroy()

These functions are always called together; this commit
combines them.

diff --git a/lib/dns/resolver.c b/lib/dns/resolver.c
index a8c298828ba2b8ae3042695cef6cf504982f5ff9..b25d565be613c46737c9e32c6fcc76c30aaa4e4d 100644 (file)
--- a/lib/dns/resolver.c
+++ b/lib/dns/resolver.c
@@ -609,8 +609,6 @@ static const dns_name_t underscore_name =
 
 static void
 destroy(dns_resolver_t *res);
-static void
-empty_bucket(dns_resolver_t *res);
 static isc_result_t
 resquery_send(resquery_t *query);
 static void
@@ -624,9 +622,9 @@ fctx_shutdown(fetchctx_t *fctx);
 static isc_result_t
 fctx_minimize_qname(fetchctx_t *fctx);
 static void
-fctx_destroy(fetchctx_t *fctx);
-static bool
-fctx_unlink(fetchctx_t *fctx);
+fctx_destroy(fetchctx_t *fctx, bool exiting);
+static void
+send_shutdown_events(dns_resolver_t *res);
 static isc_result_t
 ncache_adderesult(dns_message_t *message, dns_db_t *cache, dns_dbnode_t *node,
                  dns_rdatatype_t covers, isc_stdtime_t now, dns_ttl_t minttl,
@@ -4195,14 +4193,13 @@ cleanup:
        fctx_detach(&fctx);
 }
 
-static bool
-fctx_unlink(fetchctx_t *fctx) {
-       dns_resolver_t *res;
+static void
+fctx_destroy(fetchctx_t *fctx, bool exiting) {
+       dns_resolver_t *res = NULL;
+       isc_sockaddr_t *sa = NULL, *next_sa = NULL;
+       struct tried *tried = NULL;
        unsigned int bucketnum;
-
-       /*
-        * Caller must be holding the bucket lock.
-        */
+       bool bucket_empty = false;
 
        REQUIRE(VALID_FCTX(fctx));
        REQUIRE(fctx->state == fetchstate_done ||
@@ -4214,16 +4211,13 @@ fctx_unlink(fetchctx_t *fctx) {
        REQUIRE(atomic_load_acquire(&fctx->pending) == 0);
        REQUIRE(ISC_LIST_EMPTY(fctx->validators));
 
-       FCTXTRACE("unlink");
-
-       isc_refcount_destroy(&fctx->references);
+       FCTXTRACE("destroy");
 
        res = fctx->res;
        bucketnum = fctx->bucketnum;
 
        LOCK(&res->buckets[bucketnum].lock);
        ISC_LIST_UNLINK(res->buckets[bucketnum].fctxs, fctx, link);
-       UNLOCK(&res->buckets[bucketnum].lock);
 
        INSIST(atomic_fetch_sub_release(&res->nfctx, 1) > 0);
 
@@ -4232,29 +4226,16 @@ fctx_unlink(fetchctx_t *fctx) {
        if (atomic_load_acquire(&res->buckets[bucketnum].exiting) &&
            ISC_LIST_EMPTY(res->buckets[bucketnum].fctxs))
        {
-               return (true);
+               bucket_empty = true;
        }
+       UNLOCK(&res->buckets[bucketnum].lock);
 
-       return (false);
-}
-
-static void
-fctx_destroy(fetchctx_t *fctx) {
-       isc_sockaddr_t *sa, *next_sa;
-       struct tried *tried;
-
-       REQUIRE(VALID_FCTX(fctx));
-       REQUIRE(fctx->state == fetchstate_done ||
-               fctx->state == fetchstate_init);
-       REQUIRE(ISC_LIST_EMPTY(fctx->events));
-       REQUIRE(ISC_LIST_EMPTY(fctx->queries));
-       REQUIRE(ISC_LIST_EMPTY(fctx->finds));
-       REQUIRE(ISC_LIST_EMPTY(fctx->altfinds));
-       REQUIRE(atomic_load_acquire(&fctx->pending) == 0);
-       REQUIRE(ISC_LIST_EMPTY(fctx->validators));
-       REQUIRE(!ISC_LINK_LINKED(fctx, link));
-
-       FCTXTRACE("destroy");
+       if (bucket_empty && exiting &&
+           isc_refcount_decrement(&res->activebuckets) == 1) {
+               LOCK(&res->lock);
+               send_shutdown_events(res);
+               UNLOCK(&res->lock);
+       }
 
        isc_refcount_destroy(&fctx->references);
 
@@ -6856,10 +6837,7 @@ fctx__detach(fetchctx_t **fctxp, const char *file, unsigned int line,
 #endif
 
        if (refs == 1) {
-               if (fctx_unlink(fctx)) {
-                       empty_bucket(fctx->res);
-               }
-               fctx_destroy(fctx);
+               fctx_destroy(fctx, true);
        }
 }
 
@@ -9749,17 +9727,6 @@ send_shutdown_events(dns_resolver_t *res) {
        }
 }
 
-static void
-empty_bucket(dns_resolver_t *res) {
-       RTRACE("empty_bucket");
-
-       if (isc_refcount_decrement(&res->activebuckets) == 1) {
-               LOCK(&res->lock);
-               send_shutdown_events(res);
-               UNLOCK(&res->lock);
-       }
-}
-
 static void
 spillattimer_countdown(isc_task_t *task, isc_event_t *event) {
        dns_resolver_t *res = event->ev_arg;
@@ -10456,13 +10423,7 @@ unlock:
        UNLOCK(&res->buckets[bucketnum].lock);
 
        if (dodestroy) {
-               /*
-                * We don't care about the result of
-                * fctx_unlink() since we know we're not
-                * exiting.
-                */
-               (void)fctx_unlink(fctx);
-               fctx_destroy(fctx);
+               fctx_destroy(fctx, false);
        }
 
        if (result == ISC_R_SUCCESS) {