* The subbuffer size is least 2 bytes (minimum size: 1 page).
* This guarantees that old_commit_count + 1 != commit_count.
*/
+
+ /*
+ * Order prior updates to reserve count prior to the
+ * commit_cold cc_sb update.
+ */
+ cmm_smp_wmb();
if (caa_likely(v_cmpxchg(config, &shmp_index(handle, buf->commit_cold, idx)->cc_sb,
old_commit_count, old_commit_count + 1)
== old_commit_count)) {
/* End of exclusive subbuffer access */
v_set(config, &shmp_index(handle, buf->commit_cold, idx)->cc_sb,
commit_count);
+ /*
+ * Order later updates to reserve count after
+ * the commit cold cc_sb update.
+ */
+ cmm_smp_wmb();
lib_ring_buffer_vmcore_check_deliver(config, buf,
commit_count, idx, handle);