From f765d422d1b54f51d3735dcc584efd714007f6e2 Mon Sep 17 00:00:00 2001
From: Quentin Young <qlyoung@cumulusnetworks.com>
Date: Wed, 28 Feb 2018 16:11:42 -0500
Subject: [PATCH] lib: add atomic bitwise OR, AND

* Add support for C11 bitwise OR & AND operations
* Add atomic versions of bitfield macros

Signed-off-by: Quentin Young <qlyoung@cumulusnetworks.com>
---
 lib/frratomic.h | 16 ++++++++++++++++
 lib/zebra.h     | 10 ++++++++++
 2 files changed, 26 insertions(+)

diff --git a/lib/frratomic.h b/lib/frratomic.h
index 4ae84c4018..689b25255d 100644
--- a/lib/frratomic.h
+++ b/lib/frratomic.h
@@ -46,6 +46,8 @@
 #define atomic_exchange_explicit __atomic_exchange_n
 #define atomic_fetch_add_explicit __atomic_fetch_add
 #define atomic_fetch_sub_explicit __atomic_fetch_sub
+#define atomic_fetch_and_explicit __atomic_fetch_and
+#define atomic_fetch_or_explicit __atomic_fetch_or
 
 #define atomic_compare_exchange_weak_explicit(atom, expect, desire, mem1,      \
 					      mem2)                            \
@@ -135,6 +137,20 @@
 		*_expect = rval;                                               \
 		ret;                                                           \
 	})
+#define atomic_fetch_and_explicit(ptr, val, mem)                               \
+	({                                                                     \
+		__sync_synchronize();                                          \
+		typeof(*ptr) rval = __sync_fetch_and_and(ptr, val);            \
+		__sync_synchronize();                                          \
+		rval;                                                          \
+	})
+#define atomic_fetch_or_explicit(ptr, val, mem)                                \
+	({                                                                     \
+		__sync_synchronize();                                          \
+		typeof(*ptr) rval = __sync_fetch_and_or(ptr, val);             \
+		__sync_synchronize();                                          \
+		rval;                                                          \
+	})
 
 #else /* !HAVE___ATOMIC && !HAVE_STDATOMIC_H */
 #error no atomic functions...
diff --git a/lib/zebra.h b/lib/zebra.h
index 11bf764b63..e592118f69 100644
--- a/lib/zebra.h
+++ b/lib/zebra.h
@@ -481,6 +481,16 @@ typedef enum {
 #define UNSET_FLAG(V,F)      (V) &= ~(F)
 #define RESET_FLAG(V)        (V) = 0
 
+/* Atomic flag manipulation macros. */
+#define CHECK_FLAG_ATOMIC(PV, F)                                               \
+	((atomic_load_explicit(PV, memory_order_seq_cst)) & (F))
+#define SET_FLAG_ATOMIC(PV, F)                                                 \
+	((atomic_fetch_or_explicit(PV, (F), memory_order_seq_cst)))
+#define UNSET_FLAG_ATOMIC(PV, F)                                               \
+	((atomic_fetch_and_explicit(PV, ~(F), memory_order_seq_cst)))
+#define RESET_FLAG_ATOMIC(PV)                                                  \
+	((atomic_store_explicit(PV, 0, memory_order_seq_cst)))
+
 /* Zebra types. Used in Zserv message header. */
 typedef u_int16_t zebra_size_t;
 typedef u_int16_t zebra_command_t;
-- 
2.39.5