remove validator lock

as every validator function is loop-synchronized, it should no longer be
necessary to use a validator lock.

calling dns_validator_send(), dns_validator_cancel() or
dns_validator_destroy() from a thread other than the one on which the
validator is running will now cause an assertion failure; this should be
fine since the validator and resolver are tightly coupled, and the fetch
contexts and validators run in the same loops.

diff --git a/lib/dns/include/dns/validator.h b/lib/dns/include/dns/validator.h
index ccd4d9405e59c52d268d85efd046c77179f9ca08..b1c743e6f5bcc7e020d8dee29ef7e4d2c6389ba2 100644 (file)
--- a/lib/dns/include/dns/validator.h
+++ b/lib/dns/include/dns/validator.h
@@ -50,7 +50,6 @@
 
 #include <isc/job.h>
 #include <isc/lang.h>
-#include <isc/mutex.h>
 #include <isc/refcount.h>
 
 #include <dns/fixedname.h>
@@ -73,12 +72,10 @@
  * whatever purpose the client desires.
  */
 struct dns_validator {
-       /* Unlocked: */
        unsigned int   magic;
-       isc_mutex_t    lock;
        dns_view_t    *view;
        isc_loopmgr_t *loopmgr;
-
+       uint32_t       tid;
        isc_refcount_t references;
 
        /* Name and type of the response to be validated. */
@@ -92,7 +89,6 @@ struct dns_validator {
        isc_job_cb cb;
        void      *arg;
 
-       /* Locked by 'lock': */
        /* Validation options (_DEFER, _NONTA, etc). */
        unsigned int options;
 

diff --git a/lib/dns/validator.c b/lib/dns/validator.c
index 075d28ad72dd7059323f5605f12129ac9634a6c1..6e2efe14743eed2682baa224e49125897260d70f 100644 (file)
--- a/lib/dns/validator.c
+++ b/lib/dns/validator.c
@@ -22,6 +22,7 @@
 #include <isc/refcount.h>
 #include <isc/result.h>
 #include <isc/string.h>
+#include <isc/tid.h>
 #include <isc/util.h>
 
 #include <dns/client.h>
@@ -378,7 +379,6 @@ fetch_callback_dnskey(void *arg) {
        isc_mem_putanddetach(&resp->mctx, resp, sizeof(*resp));
 
        validator_log(val, ISC_LOG_DEBUG(3), "in fetch_callback_dnskey");
-       LOCK(&val->lock);
        fetch = val->fetch;
        val->fetch = NULL;
        if (CANCELED(val)) {
@@ -428,7 +428,6 @@ fetch_callback_dnskey(void *arg) {
                        validator_done(val, DNS_R_BROKENCHAIN);
                }
        }
-       UNLOCK(&val->lock);
 
        if (fetch != NULL) {
                dns_resolver_destroyfetch(&fetch);
@@ -471,7 +470,6 @@ fetch_callback_ds(void *arg) {
        }
 
        validator_log(val, ISC_LOG_DEBUG(3), "in fetch_callback_ds");
-       LOCK(&val->lock);
        fetch = val->fetch;
        val->fetch = NULL;
 
@@ -577,7 +575,6 @@ fetch_callback_ds(void *arg) {
 done:
 
        isc_mem_putanddetach(&resp->mctx, resp, sizeof(*resp));
-       UNLOCK(&val->lock);
 
        if (fetch != NULL) {
                dns_resolver_destroyfetch(&fetch);
@@ -603,7 +600,6 @@ validator_callback_dnskey(void *arg) {
        subvalidator->parent = NULL;
 
        validator_log(val, ISC_LOG_DEBUG(3), "in validator_callback_dnskey");
-       LOCK(&val->lock);
        if (CANCELED(val)) {
                validator_done(val, ISC_R_CANCELED);
        } else if (eresult == ISC_R_SUCCESS) {
@@ -640,8 +636,6 @@ validator_callback_dnskey(void *arg) {
                validator_done(val, DNS_R_BROKENCHAIN);
        }
 
-       UNLOCK(&val->lock);
-
        dns_validator_destroy(&subvalidator);
        dns_validator_detach(&val);
 }
@@ -662,7 +656,6 @@ validator_callback_ds(void *arg) {
        subvalidator->parent = NULL;
 
        validator_log(val, ISC_LOG_DEBUG(3), "in validator_callback_ds");
-       LOCK(&val->lock);
        if (CANCELED(val)) {
                validator_done(val, ISC_R_CANCELED);
        } else if (eresult == ISC_R_SUCCESS) {
@@ -699,7 +692,6 @@ validator_callback_ds(void *arg) {
                              isc_result_totext(eresult));
                validator_done(val, DNS_R_BROKENCHAIN);
        }
-       UNLOCK(&val->lock);
 
        dns_validator_destroy(&subvalidator);
        dns_validator_detach(&val);
@@ -722,7 +714,6 @@ validator_callback_cname(void *arg) {
        val->subvalidator = NULL;
 
        validator_log(val, ISC_LOG_DEBUG(3), "in validator_callback_cname");
-       LOCK(&val->lock);
        if (CANCELED(val)) {
                validator_done(val, ISC_R_CANCELED);
        } else if (eresult == ISC_R_SUCCESS) {
@@ -742,8 +733,6 @@ validator_callback_cname(void *arg) {
                validator_done(val, DNS_R_BROKENCHAIN);
        }
 
-       UNLOCK(&val->lock);
-
        dns_validator_destroy(&subvalidator);
        dns_validator_detach(&val);
 }
@@ -766,7 +755,6 @@ validator_callback_nsec(void *arg) {
        val->subvalidator = NULL;
 
        validator_log(val, ISC_LOG_DEBUG(3), "in validator_callback_nsec");
-       LOCK(&val->lock);
        if (CANCELED(val)) {
                validator_done(val, ISC_R_CANCELED);
        } else if (result != ISC_R_SUCCESS) {
@@ -841,8 +829,6 @@ validator_callback_nsec(void *arg) {
                }
        }
 
-       UNLOCK(&val->lock);
-
        dns_validator_destroy(&subvalidator);
        dns_validator_detach(&val);
 }
@@ -2902,8 +2888,6 @@ validator_start(void *arg) {
 
        validator_log(val, ISC_LOG_DEBUG(3), "starting");
 
-       LOCK(&val->lock);
-
        if (val->rdataset != NULL && val->sigrdataset != NULL) {
                isc_result_t saved_result;
 
@@ -2987,8 +2971,6 @@ validator_start(void *arg) {
                validator_done(val, result);
        }
 
-       UNLOCK(&val->lock);
-
        dns_validator_detach(&val);
 }
 
@@ -3007,7 +2989,8 @@ dns_validator_create(dns_view_t *view, dns_name_t *name, dns_rdatatype_t type,
        REQUIRE(validatorp != NULL && *validatorp == NULL);
 
        val = isc_mem_get(view->mctx, sizeof(*val));
-       *val = (dns_validator_t){ .result = ISC_R_FAILURE,
+       *val = (dns_validator_t){ .tid = isc_tid(),
+                                 .result = ISC_R_FAILURE,
                                  .rdataset = rdataset,
                                  .sigrdataset = sigrdataset,
                                  .name = name,
@@ -3024,7 +3007,6 @@ dns_validator_create(dns_view_t *view, dns_name_t *name, dns_rdatatype_t type,
                dns_message_attach(message, &val->message);
        }
        dns_view_attach(view, &val->view);
-       isc_mutex_init(&val->lock);
 
        result = dns_view_getsecroots(val->view, &val->keytable);
        if (result != ISC_R_SUCCESS) {
@@ -3050,7 +3032,6 @@ dns_validator_create(dns_view_t *view, dns_name_t *name, dns_rdatatype_t type,
        return (ISC_R_SUCCESS);
 
 cleanup:
-       isc_mutex_destroy(&val->lock);
        if (val->message != NULL) {
                dns_message_detach(&val->message);
        }
@@ -3063,12 +3044,10 @@ cleanup:
 void
 dns_validator_send(dns_validator_t *validator) {
        REQUIRE(VALID_VALIDATOR(validator));
-
-       LOCK(&validator->lock);
+       REQUIRE(validator->tid == isc_tid());
 
        INSIST((validator->options & DNS_VALIDATOR_DEFER) != 0);
        validator->options &= ~DNS_VALIDATOR_DEFER;
-       UNLOCK(&validator->lock);
 
        dns_validator_ref(validator);
        isc_job_run(validator->loopmgr, validator_start, validator);
@@ -3077,8 +3056,7 @@ dns_validator_send(dns_validator_t *validator) {
 void
 dns_validator_cancel(dns_validator_t *validator) {
        REQUIRE(VALID_VALIDATOR(validator));
-
-       LOCK(&validator->lock);
+       REQUIRE(validator->tid == isc_tid());
 
        validator_log(validator, ISC_LOG_DEBUG(3), "dns_validator_cancel");
 
@@ -3096,7 +3074,6 @@ dns_validator_cancel(dns_validator_t *validator) {
 
                validator->attributes |= VALATTR_CANCELED;
        }
-       UNLOCK(&validator->lock);
 }
 
 static void
@@ -3121,7 +3098,6 @@ destroy_validator(dns_validator_t *val) {
        if (val->siginfo != NULL) {
                isc_mem_put(mctx, val->siginfo, sizeof(*val->siginfo));
        }
-       isc_mutex_destroy(&val->lock);
        dns_view_detach(&val->view);
        if (val->message != NULL) {
                dns_message_detach(&val->message);
@@ -3139,10 +3115,9 @@ dns_validator_destroy(dns_validator_t **validatorp) {
        *validatorp = NULL;
 
        REQUIRE(VALID_VALIDATOR(val));
+       REQUIRE(val->tid == isc_tid());
 
-       LOCK(&val->lock);
        validator_log(val, ISC_LOG_DEBUG(4), "dns_validator_destroy");
-       UNLOCK(&val->lock);
 
        dns_validator_detach(&val);
 }