Fix: ACCESS_ONCE() removed in kernel 4.15

[lttng-modules.git] / lib / ringbuffer / backend_internal.h

diff --git a/lib/ringbuffer/backend_internal.h b/lib/ringbuffer/backend_internal.h
index 2e59b68b482a6cc3520d87c09278663aaa237553..dc69ecf39ff41591f3d65908252c4276751c3c6a 100644 (file)
--- a/lib/ringbuffer/backend_internal.h
+++ b/lib/ringbuffer/backend_internal.h
@@ -23,6 +23,7 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#include <wrapper/compiler.h>
 #include <wrapper/ringbuffer/config.h>
 #include <wrapper/ringbuffer/backend_types.h>
 #include <wrapper/ringbuffer/frontend_types.h>
@@ -171,7 +172,7 @@ void subbuffer_id_set_noref_offset(const struct lib_ring_buffer_config *config,
                tmp |= offset << SB_ID_OFFSET_SHIFT;
                tmp |= SB_ID_NOREF_MASK;
                /* Volatile store, read concurrently by readers. */
-               ACCESS_ONCE(*id) = tmp;
+               WRITE_ONCE(*id, tmp);
        }
 }
 
@@ -379,7 +380,7 @@ void lib_ring_buffer_clear_noref(const struct lib_ring_buffer_config *config,
         * Performing a volatile access to read the sb_pages, because we want to
         * read a coherent version of the pointer and the associated noref flag.
         */
-       id = ACCESS_ONCE(bufb->buf_wsb[idx].id);
+       id = READ_ONCE(bufb->buf_wsb[idx].id);
        for (;;) {
                /* This check is called on the fast path for each record. */
                if (likely(!subbuffer_id_is_noref(config, id))) {
@@ -448,7 +449,7 @@ int update_read_sb_index(const struct lib_ring_buffer_config *config,
        if (config->mode == RING_BUFFER_OVERWRITE) {
                /*
                 * Exchange the target writer subbuffer with our own unused
-                * subbuffer. No need to use ACCESS_ONCE() here to read the
+                * subbuffer. No need to use READ_ONCE() here to read the
                 * old_wpage, because the value read will be confirmed by the
                 * following cmpxchg().
                 */