mcslock: add MCS queued lock implementation

[dpdk.git] / doc / guides / rel_notes / release_19_08.rst

diff --git a/doc/guides/rel_notes/release_19_08.rst b/doc/guides/rel_notes/release_19_08.rst
index a01712c9c3257da84e908c8290deb0df24e671fa..defbc5e27cbfcfaa102263529f3b0f758f193ff2 100644 (file)
--- a/doc/guides/rel_notes/release_19_08.rst
+++ b/doc/guides/rel_notes/release_19_08.rst
@@ -56,6 +56,13 @@ New Features
      Also, make sure to start the actual text at the margin.
      =========================================================
 
+* **Added MCS lock.**
+
+  MCS lock provides scalability by spinning on a CPU/thread local variable
+  which avoids expensive cache bouncings.
+  It provides fairness by maintaining a list of acquirers and passing
+  the lock to each CPU/thread in the order they acquired the lock.
+
 * **Updated the EAL Pseudo-random Number Generator.**
 
   The lrand48()-based rte_rand() function is replaced with a