Experiment: brutally remove locking in isc_result

- bind resolver tasks to queues, hashed by bucket

lib/dns/acl.c

@@ -130,7 +130,7 @@ dns_acl_none(isc_mem_t *mctx, dns_acl_t **target) {
  * If pos is false, test whether acl is set to "{ none; }"
  */
 static bool
-dns_acl_isanyornone(dns_acl_t *acl, bool pos)
+dns_acl_isanyornone(const dns_acl_t *acl, bool pos)
 {
 	/* Should never happen but let's be safe */
 	if (acl == NULL ||
@@ -157,7 +157,7 @@ dns_acl_isanyornone(dns_acl_t *acl, bool pos)
  * Test whether acl is set to "{ any; }"
  */
 bool
-dns_acl_isany(dns_acl_t *acl)
+dns_acl_isany(const dns_acl_t *acl)
 {
 	return (dns_acl_isanyornone(acl, true));
 }
@@ -166,7 +166,7 @@ dns_acl_isany(dns_acl_t *acl)
  * Test whether acl is set to "{ none; }"
  */
 bool
-dns_acl_isnone(dns_acl_t *acl)
+dns_acl_isnone(const dns_acl_t *acl)
 {
 	return (dns_acl_isanyornone(acl, false));
 }
@@ -198,6 +198,20 @@ dns_acl_match(const isc_netaddr_t *reqaddr,
 	REQUIRE(reqaddr != NULL);
 	REQUIRE(matchelt == NULL || *matchelt == NULL);
 
+	/*
+	 * We don't care about matchelt, see if maybe that's 'any' or 'none'
+	 * ACL to speed things up.
+	 */
+	if (matchelt == NULL) {
+		if (dns_acl_isany(acl)) {
+			*match = 1;
+			return (ISC_R_SUCCESS);
+		} else if (dns_acl_isnone(acl)) {
+			*match = -1;
+			return (ISC_R_SUCCESS);
+		}
+	}
+
 	if (env != NULL && env->match_mapped &&
 	    addr->family == AF_INET6 &&
 	    IN6_IS_ADDR_V4MAPPED(&addr->type.in6))

lib/dns/client.c

@@ -462,7 +462,7 @@ dns_client_createx(isc_mem_t *mctx, isc_appctx_t *actx,
 	client->timermgr = timermgr;
 
 	client->task = NULL;
-	result = isc_task_create(client->taskmgr, 50, &client->task);
+	result = isc_task_create(client->taskmgr, 0, &client->task);
 	if (result != ISC_R_SUCCESS)
 		goto cleanup;
 

lib/dns/dispatch.c

@@ -2959,7 +2959,7 @@ dispatch_createudp(dns_dispatchmgr_t *mgr, isc_socketmgr_t *sockmgr,
 	}
 	for (i = 0; i < disp->ntasks; i++) {
 		disp->task[i] = NULL;
-		result = isc_task_create(taskmgr, 50, &disp->task[i]);
+		result = isc_task_create(taskmgr, 0, &disp->task[i]);
 		if (result != ISC_R_SUCCESS) {
 			while (--i >= 0) {
 				isc_task_shutdown(disp->task[i]);

lib/dns/include/dns/acl.h

@@ -130,13 +130,13 @@ dns_acl_none(isc_mem_t *mctx, dns_acl_t **target);
  */
 
 bool
-dns_acl_isany(dns_acl_t *acl);
+dns_acl_isany(const dns_acl_t *acl);
 /*%<
  * Test whether ACL is set to "{ any; }"
  */
 
 bool
-dns_acl_isnone(dns_acl_t *acl);
+dns_acl_isnone(const dns_acl_t *acl);
 /*%<
  * Test whether ACL is set to "{ none; }"
  */

lib/dns/include/dns/name.h

@@ -75,6 +75,7 @@
 #include <dns/types.h>
 
 ISC_LANG_BEGINDECLS
+#define DNS_NAME_USEINLINE 1
 
 /*****
  ***** Labels
@@ -205,7 +206,7 @@ typedef isc_result_t (*dns_name_totextfilter_t)(isc_buffer_t *target,
  ***/
 
 void
-dns_name_init(dns_name_t *name, unsigned char *offsets);
+dns__name_init(dns_name_t *name, unsigned char *offsets);
 /*%<
  * Initialize 'name'.
  *
@@ -226,7 +227,7 @@ dns_name_init(dns_name_t *name, unsigned char *offsets);
  */
 
 void
-dns_name_reset(dns_name_t *name);
+dns__name_reset(dns_name_t *name);
 /*%<
  * Reinitialize 'name'.
  *
@@ -276,7 +277,7 @@ dns_name_isvalid(const dns_name_t *name);
  ***/
 
 void
-dns_name_setbuffer(dns_name_t *name, isc_buffer_t *buffer);
+dns__name_setbuffer(dns_name_t *name, isc_buffer_t *buffer);
 /*%<
  * Dedicate a buffer for use with 'name'.
  *
@@ -318,7 +319,7 @@ dns_name_hasbuffer(const dns_name_t *name);
  ***/
 
 bool
-dns_name_isabsolute(const dns_name_t *name);
+dns__name_isabsolute(const dns_name_t *name);
 /*%<
  * Does 'name' end in the root label?
  *
@@ -567,7 +568,7 @@ dns_name_matcheswildcard(const dns_name_t *name, const dns_name_t *wname);
  ***/
 
 unsigned int
-dns_name_countlabels(const dns_name_t *name);
+dns__name_countlabels(const dns_name_t *name);
 /*%<
  * How many labels does 'name' have?
  *
@@ -675,7 +676,7 @@ dns_name_fromregion(dns_name_t *name, const isc_region_t *r);
  */
 
 void
-dns_name_toregion(const dns_name_t *name, isc_region_t *r);
+dns__name_toregion(const dns_name_t *name, isc_region_t *r);
 /*%<
  * Make 'r' refer to 'name'.
  *
@@ -985,7 +986,7 @@ dns_name_concatenate(const dns_name_t *prefix, const dns_name_t *suffix,
  */
 
 void
-dns_name_split(const dns_name_t *name, unsigned int suffixlabels,
+dns__name_split(const dns_name_t *name, unsigned int suffixlabels,
 	       dns_name_t *prefix, dns_name_t *suffix);
 /*%<
  *
@@ -1385,7 +1386,7 @@ do { \
 
 #define DNS_NAME_SPLIT(n, l, p, s) \
 do { \
-	dns_name_t *_n = (n); \
+	const dns_name_t *_n = (n); \
 	dns_name_t *_p = (p); \
 	dns_name_t *_s = (s); \
 	unsigned int _l = (l); \
@@ -1405,6 +1406,16 @@ do { \
 #define dns_name_toregion(n, r)		DNS_NAME_TOREGION(n, r)
 #define dns_name_split(n, l, p, s)	DNS_NAME_SPLIT(n, l, p, s)
 
+#else
+
+#define dns_name_init(n, o)		dns__name_init(n, o)
+#define dns_name_reset(n)		dns__name_reset(n)
+#define dns_name_setbuffer(n, b)	dns__name_setbuffer(n, b)
+#define dns_name_countlabels(n)		dns__name_countlabels(n)
+#define dns_name_isabsolute(n)		dns__name_isabsolute(n)
+#define dns_name_toregion(n, r)		dns__name_toregion(n, r)
+#define dns_name_split(n, l, p, s)	dns__name_split(n, l, p, s)
+
 #endif /* DNS_NAME_USEINLINE */
 
 #endif /* DNS_NAME_H */

lib/dns/name.c

@@ -176,7 +176,7 @@ set_offsets(const dns_name_t *name, unsigned char *offsets,
 	    dns_name_t *set_name);
 
 void
-dns_name_init(dns_name_t *name, unsigned char *offsets) {
+dns__name_init(dns_name_t *name, unsigned char *offsets) {
 	/*
 	 * Initialize 'name'.
 	 */
@@ -184,7 +184,7 @@ dns_name_init(dns_name_t *name, unsigned char *offsets) {
 }
 
 void
-dns_name_reset(dns_name_t *name) {
+dns__name_reset(dns_name_t *name) {
 	REQUIRE(VALID_NAME(name));
 	REQUIRE(BINDABLE(name));
 
@@ -250,7 +250,7 @@ dns_name_isvalid(const dns_name_t *name) {
 }
 
 void
-dns_name_setbuffer(dns_name_t *name, isc_buffer_t *buffer) {
+dns__name_setbuffer(dns_name_t *name, isc_buffer_t *buffer) {
 	/*
 	 * Dedicate a buffer for use with 'name'.
 	 */
@@ -277,7 +277,7 @@ dns_name_hasbuffer(const dns_name_t *name) {
 }
 
 bool
-dns_name_isabsolute(const dns_name_t *name) {
+dns__name_isabsolute(const dns_name_t *name) {
 
 	/*
 	 * Does 'name' end in the root label?
@@ -849,7 +849,7 @@ dns_name_matcheswildcard(const dns_name_t *name, const dns_name_t *wname) {
 }
 
 unsigned int
-dns_name_countlabels(const dns_name_t *name) {
+dns__name_countlabels(const dns_name_t *name) {
 	/*
 	 * How many labels does 'name' have?
 	 */
@@ -1017,7 +1017,7 @@ dns_name_fromregion(dns_name_t *name, const isc_region_t *r) {
 }
 
 void
-dns_name_toregion(const dns_name_t *name, isc_region_t *r) {
+dns__name_toregion(const dns_name_t *name, isc_region_t *r) {
 	/*
 	 * Make 'r' refer to 'name'.
 	 */
@@ -2130,7 +2130,7 @@ dns_name_concatenate(const dns_name_t *prefix, const dns_name_t *suffix,
 }
 
 void
-dns_name_split(const dns_name_t *name, unsigned int suffixlabels,
+dns__name_split(const dns_name_t *name, unsigned int suffixlabels,
 	       dns_name_t *prefix, dns_name_t *suffix)
 
 {

lib/dns/resolver.c

@@ -4382,8 +4382,8 @@ fctx_shutdown(fetchctx_t *fctx) {
 	 */
 	if (fctx->state != fetchstate_init) {
 		cevent = &fctx->control_event;
-		isc_task_send(fctx->res->buckets[fctx->bucketnum].task,
-			      &cevent);
+		isc_task_sendto(fctx->res->buckets[fctx->bucketnum].task,
+			        &cevent, fctx->bucketnum);
 	}
 }
 
@@ -9925,7 +9925,7 @@ dns_resolver_create(dns_view_t *view,
 		if (result != ISC_R_SUCCESS)
 			goto cleanup_buckets;
 		res->buckets[i].task = NULL;
-		result = isc_task_create(taskmgr, 0, &res->buckets[i].task);
+		result = isc_task_create_bound(taskmgr, 0, &res->buckets[i].task, i);
 		if (result != ISC_R_SUCCESS) {
 			DESTROYLOCK(&res->buckets[i].lock);
 			goto cleanup_buckets;

lib/isc/include/isc/task.h

@@ -136,6 +136,10 @@ struct isc_task {
 isc_result_t
 isc_task_create(isc_taskmgr_t *manager, unsigned int quantum,
 		isc_task_t **taskp);
+
+isc_result_t
+isc_task_create_bound(isc_taskmgr_t *manager, unsigned int quantum,
+		      isc_task_t **taskp, int threadid);
 /*%<
  * Create a task.
  *

lib/isc/result.c

@@ -257,8 +257,6 @@ isc_result_tomany_helper(resulttable_list_t *tables, isc_result_t result) {
 
 	initialize();
 
-	LOCK(&lock);
-
 	text = NULL;
 	for (table = ISC_LIST_HEAD(*tables);
 	     table != NULL;
@@ -280,8 +278,6 @@ isc_result_tomany_helper(resulttable_list_t *tables, isc_result_t result) {
 		text = isc_msgcat_get(isc_msgcat, ISC_RESULT_UNAVAILABLESET,
 				      1, "(result code text not available)");
 
-	UNLOCK(&lock);
-
 	return (text);
 }
 

lib/isc/rwlock.c

@@ -236,6 +236,7 @@ isc_rwlock_destroy(isc_rwlock_t *rwl) {
 
 static isc_result_t
 isc__rwlock_lock(isc_rwlock_t *rwl, isc_rwlocktype_t type) {
+	return (ISC_R_SUCCESS);
 	int32_t cntflag;
 
 	REQUIRE(VALID_RWLOCK(rwl));
@@ -357,6 +358,7 @@ isc__rwlock_lock(isc_rwlock_t *rwl, isc_rwlocktype_t type) {
 
 isc_result_t
 isc_rwlock_lock(isc_rwlock_t *rwl, isc_rwlocktype_t type) {
+	return (ISC_R_SUCCESS);
 	int32_t cnt = 0;
 	int32_t max_cnt = rwl->spins * 2 + 10;
 	isc_result_t result = ISC_R_SUCCESS;
@@ -379,6 +381,7 @@ isc_rwlock_lock(isc_rwlock_t *rwl, isc_rwlocktype_t type) {
 
 isc_result_t
 isc_rwlock_trylock(isc_rwlock_t *rwl, isc_rwlocktype_t type) {
+	return (ISC_R_SUCCESS);
 	int32_t cntflag;
 
 	REQUIRE(VALID_RWLOCK(rwl));
@@ -450,6 +453,7 @@ isc_rwlock_trylock(isc_rwlock_t *rwl, isc_rwlocktype_t type) {
 
 isc_result_t
 isc_rwlock_tryupgrade(isc_rwlock_t *rwl) {
+	return (ISC_R_SUCCESS);
 	REQUIRE(VALID_RWLOCK(rwl));
 
 	{
@@ -483,6 +487,7 @@ isc_rwlock_tryupgrade(isc_rwlock_t *rwl) {
 
 void
 isc_rwlock_downgrade(isc_rwlock_t *rwl) {
+	return;
 	int32_t prev_readers;
 
 	REQUIRE(VALID_RWLOCK(rwl));
@@ -511,6 +516,7 @@ isc_rwlock_downgrade(isc_rwlock_t *rwl) {
 
 isc_result_t
 isc_rwlock_unlock(isc_rwlock_t *rwl, isc_rwlocktype_t type) {
+	return (ISC_R_SUCCESS);
 	int32_t prev_cnt;
 
 	REQUIRE(VALID_RWLOCK(rwl));

lib/isc/stats.c

@@ -165,6 +165,7 @@ isc_stats_create(isc_mem_t *mctx, isc_stats_t **statsp, int ncounters) {
 
 void
 isc_stats_increment(isc_stats_t *stats, isc_statscounter_t counter) {
+	return;
 	REQUIRE(ISC_STATS_VALID(stats));
 	REQUIRE(counter < stats->ncounters);
 
@@ -174,6 +175,7 @@ isc_stats_increment(isc_stats_t *stats, isc_statscounter_t counter) {
 
 void
 isc_stats_decrement(isc_stats_t *stats, isc_statscounter_t counter) {
+	return;
 	REQUIRE(ISC_STATS_VALID(stats));
 	REQUIRE(counter < stats->ncounters);
 

lib/isc/task.c

@@ -104,6 +104,7 @@ struct isc__task {
 	char				name[16];
 	void *				tag;
 	unsigned int			threadid;
+	bool				bound;
 	/* Locked by task manager lock. */
 	LINK(isc__task_t)		link;
 	LINK(isc__task_t)		ready_link;
@@ -171,8 +172,7 @@ void
 isc__taskmgr_resume(isc_taskmgr_t *manager0);
 
 
-#define DEFAULT_TASKMGR_QUANTUM		10
-#define DEFAULT_DEFAULT_QUANTUM		5
+#define DEFAULT_DEFAULT_QUANTUM		25
 #define FINISHED(m)			((m)->exiting && EMPTY((m)->tasks))
 
 /*%
@@ -243,7 +243,14 @@ task_finished(isc__task_t *task) {
 
 isc_result_t
 isc_task_create(isc_taskmgr_t *manager0, unsigned int quantum,
-		 isc_task_t **taskp)
+		isc_task_t **taskp)
+{
+	return (isc_task_create_bound(manager0, quantum, taskp, -1));
+}
+
+isc_result_t
+isc_task_create_bound(isc_taskmgr_t *manager0, unsigned int quantum,
+		      isc_task_t **taskp, int threadid)
 {
 	isc__taskmgr_t *manager = (isc__taskmgr_t *)manager0;
 	isc__task_t *task;
@@ -258,9 +265,15 @@ isc_task_create(isc_taskmgr_t *manager0, unsigned int quantum,
 		return (ISC_R_NOMEMORY);
 	XTRACE("isc_task_create");
 	task->manager = manager;
-	task->threadid = atomic_fetch_add_explicit(&manager->curq, 1,
-						   memory_order_relaxed)
-						   % manager->workers;
+	if (threadid == -1) {
+		task->bound = false;
+		task->threadid = atomic_fetch_add_explicit(&manager->curq, 1,
+							   memory_order_relaxed)
+							   % manager->workers;
+	} else {
+		task->bound = true;
+		task->threadid = threadid % manager->workers;
+	}
 	result = isc_mutex_init(&task->lock);
 	if (result != ISC_R_SUCCESS) {
 		isc_mem_put(manager->mctx, task, sizeof(*task));
@@ -494,7 +507,9 @@ isc_task_sendto(isc_task_t *task0, isc_event_t **eventp, int c) {
 	REQUIRE(VALID_TASK(task));
 	XTRACE("isc_task_send");
 
-	if (c < 0) {
+	if (task->bound) {
+		c = task->threadid;
+	} else if (c < 0) {
 		c = atomic_fetch_add_explicit(&task->manager->curq, 1,
 					      memory_order_relaxed);
 	}
@@ -544,7 +559,9 @@ isc_task_sendtoanddetach(isc_task_t **taskp, isc_event_t **eventp, int c) {
 	REQUIRE(VALID_TASK(task));
 	XTRACE("isc_task_sendanddetach");
 
-	if (c < 0) {
+	if (task->bound) {
+		c = task->threadid;
+	} else if (c < 0) {
 		c = atomic_fetch_add_explicit(&task->manager->curq, 1,
 					      memory_order_relaxed);
 	}

lib/ns/client.c

@@ -2964,7 +2964,7 @@ client_create(ns_clientmgr_t *manager, ns_client_t **clientp) {
 	ns_server_attach(manager->sctx, &client->sctx);
 
 	client->task = NULL;
-	result = isc_task_create(manager->taskmgr, 50, &client->task);
+	result = isc_task_create(manager->taskmgr, 0, &client->task);
 	if (result != ISC_R_SUCCESS)
 		goto cleanup_client;
 	isc_task_setname(client->task, "client", client);