crypto/threads_*: remove CRYPTO_atomic_{read|write}.

CRYPTO_atomic_read was added with intention to read statistics counters,
but readings are effectively indistinguishable from regular load (even
in non-lock-free case). This is because you can get out-dated value in
both cases. CRYPTO_atomic_write was added for symmetry and was never used.

Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
(Merged from https://github.com/openssl/openssl/pull/6883)

3 files changed, 0 insertions, 62 deletions

diff --git a/crypto/threads_none.c b/crypto/threads_none.c
index ab6db8e36b..4b1940ae44 100644
--- a/crypto/threads_none.c
+++ b/crypto/threads_none.c
@@ -128,18 +128,6 @@ int CRYPTO_atomic_add(int *val, int amount, int *ret, CRYPTO_RWLOCK *lock)
     return 1;
 }
 
-int CRYPTO_atomic_read(int *val, int *ret, CRYPTO_RWLOCK *lock)
-{
-    *ret = *val;
-    return 1;
-}
-
-int CRYPTO_atomic_write(int *val, int n, CRYPTO_RWLOCK *lock)
-{
-    *val = n;
-    return 1;
-}
-
 int openssl_init_fork_handlers(void)
 {
     return 0;
diff --git a/crypto/threads_pthread.c b/crypto/threads_pthread.c
index 8d30e1c69f..5a59779ebb 100644
--- a/crypto/threads_pthread.c
+++ b/crypto/threads_pthread.c
@@ -175,44 +175,6 @@ int CRYPTO_atomic_add(int *val, int amount, int *ret, CRYPTO_RWLOCK *lock)
     return 1;
 }
 
-int CRYPTO_atomic_read(int *val, int *ret, CRYPTO_RWLOCK *lock)
-{
-# if defined(__GNUC__) && defined(__ATOMIC_ACQUIRE)
-    if (__atomic_is_lock_free(sizeof(*val), val)) {
-        __atomic_load(val, ret, __ATOMIC_ACQUIRE);
-        return 1;
-    }
-# endif
-    if (!CRYPTO_THREAD_read_lock(lock))
-        return 0;
-
-    *ret  = *val;
-
-    if (!CRYPTO_THREAD_unlock(lock))
-        return 0;
-
-    return 1;
-}
-
-int CRYPTO_atomic_write(int *val, int n, CRYPTO_RWLOCK *lock)
-{
-# if defined(__GNUC__) && defined(__ATOMIC_RELEASE)
-    if (__atomic_is_lock_free(sizeof(*val), val)) {
-        __atomic_store(val, &n, __ATOMIC_RELEASE);
-        return 1;
-    }
-# endif
-    if (!CRYPTO_THREAD_write_lock(lock))
-        return 0;
-
-    *val = n;
-
-    if (!CRYPTO_THREAD_unlock(lock))
-        return 0;
-
-    return 1;
-}
-
 # ifdef OPENSSL_SYS_UNIX
 static pthread_once_t fork_once_control = PTHREAD_ONCE_INIT;
 
diff --git a/crypto/threads_win.c b/crypto/threads_win.c
index 7fdbc1f67f..d8fdfb74f5 100644
--- a/crypto/threads_win.c
+++ b/crypto/threads_win.c
@@ -155,18 +155,6 @@ int CRYPTO_atomic_add(int *val, int amount, int *ret, CRYPTO_RWLOCK *lock)
     return 1;
 }
 
-int CRYPTO_atomic_read(int *val, int *ret, CRYPTO_RWLOCK *lock)
-{
-    *ret = InterlockedCompareExchange(val, 0, 0);
-    return 1;
-}
-
-int CRYPTO_atomic_write(int *val, int n, CRYPTO_RWLOCK *lock)
-{
-    InterlockedExchange(val, n);
-    return 1;
-}
-
 int openssl_init_fork_handlers(void)
 {
     return 0;