Add locking to atomic operations in rw/rcu tests

I neglected to add locks to the calls to CRYPTO_atomic_add in these
test, which on newer compilers is fine, as atomic operations are
defined.  However on older compilers the __ATOMIC_ACQ_REL definition is
missing causing these function to be implemented using an rwlock, which
when NULL causes the locks to fail.

Fix this my creating the lock and using them appropriately

test/threadstest.c

@@ -111,6 +111,7 @@ static int rwwriter2_iterations = 0;
 static int *rwwriter_ptr = NULL;
 static int rw_torture_result = 1;
 static CRYPTO_RWLOCK *rwtorturelock = NULL;
+static CRYPTO_RWLOCK *atomiclock = NULL;
 
 static void rwwriter_fn(int id, int *iterations)
 {
@@ -150,7 +151,7 @@ static void rwwriter1_fn(void)
 
     TEST_info("Starting writer1");
     rwwriter_fn(1, &rwwriter1_iterations);
-    CRYPTO_atomic_add(&rwwriter1_done, 1, &local, NULL);
+    CRYPTO_atomic_add(&rwwriter1_done, 1, &local, atomiclock);
 }
 
 static void rwwriter2_fn(void)
@@ -159,7 +160,7 @@ static void rwwriter2_fn(void)
 
     TEST_info("Starting writer 2");
     rwwriter_fn(2, &rwwriter2_iterations);
-    CRYPTO_atomic_add(&rwwriter2_done, 1, &local, NULL);
+    CRYPTO_atomic_add(&rwwriter2_done, 1, &local, atomiclock);
 }
 
 static void rwreader_fn(int *iterations)
@@ -174,8 +175,8 @@ static void rwreader_fn(int *iterations)
             abort();
 
     while (lw1 != 1 || lw2 != 1) {
-        CRYPTO_atomic_add(&rwwriter1_done, 0, &lw1, NULL);
-        CRYPTO_atomic_add(&rwwriter2_done, 0, &lw2, NULL);
+        CRYPTO_atomic_add(&rwwriter1_done, 0, &lw1, atomiclock);
+        CRYPTO_atomic_add(&rwwriter2_done, 0, &lw2, atomiclock);
 
         count++;
         if (rwwriter_ptr != NULL && old > *rwwriter_ptr) {
@@ -223,6 +224,7 @@ static int _torture_rw(void)
     struct timeval dtime;
 
     rwtorturelock = CRYPTO_THREAD_lock_new();
+    atomiclock = CRYPTO_THREAD_lock_new();
     rwwriter1_iterations = 0;
     rwwriter2_iterations = 0;
     rwreader1_iterations = 0;
@@ -264,6 +266,7 @@ static int _torture_rw(void)
         ret = 1;
 out:
     CRYPTO_THREAD_lock_free(rwtorturelock);
+    CRYPTO_THREAD_lock_free(atomiclock);
     rwtorturelock = NULL;
     return ret;
 }
@@ -336,7 +339,7 @@ static void writer1_fn(void)
 
     TEST_info("Starting writer1");
     writer_fn(1, &writer1_iterations);
-    CRYPTO_atomic_add(&writer1_done, 1, &local, NULL);
+    CRYPTO_atomic_add(&writer1_done, 1, &local, atomiclock);
 }
 
 static void writer2_fn(void)
@@ -345,7 +348,7 @@ static void writer2_fn(void)
 
     TEST_info("Starting writer2");
     writer_fn(2, &writer2_iterations);
-    CRYPTO_atomic_add(&writer2_done, 1, &local, NULL);
+    CRYPTO_atomic_add(&writer2_done, 1, &local, atomiclock);
 }
 
 static void reader_fn(int *iterations)
@@ -358,8 +361,8 @@ static void reader_fn(int *iterations)
     int lw2 = 0;
 
     while (lw1 != 1 || lw2 != 1) {
-        CRYPTO_atomic_add(&writer1_done, 0, &lw1, NULL);
-        CRYPTO_atomic_add(&writer2_done, 0, &lw2, NULL);
+        CRYPTO_atomic_add(&writer1_done, 0, &lw1, atomiclock);
+        CRYPTO_atomic_add(&writer2_done, 0, &lw2, atomiclock);
         count++;
         ossl_rcu_read_lock(rcu_lock);
         valp = ossl_rcu_deref(&writer_ptr);
@@ -403,6 +406,7 @@ static int _torture_rcu(void)
     double tottime;
     double avr, avw;
 
+    atomiclock = CRYPTO_THREAD_lock_new();
     memset(&writer1, 0, sizeof(thread_t));
     memset(&writer2, 0, sizeof(thread_t));
     memset(&reader1, 0, sizeof(thread_t));
@@ -443,6 +447,7 @@ static int _torture_rcu(void)
     TEST_info("Average write time %e/write", avw);
 
     ossl_rcu_lock_free(rcu_lock);
+    CRYPTO_THREAD_lock_free(atomiclock);
     if (!TEST_int_eq(rcu_torture_result, 1))
         return 0;