locking/barriers, kcsan: Add instrumentation for barriers

Adds the required KCSAN instrumentation for barriers if CONFIG_SMP.
KCSAN supports modeling the effects of:

	smp_mb()
	smp_rmb()
	smp_wmb()
	smp_store_release()

Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

diff --git a/include/asm-generic/barrier.h b/include/asm-generic/barrier.h
index 640f094..27a9c9e 100644 (file)
--- a/include/asm-generic/barrier.h
+++ b/include/asm-generic/barrier.h
@@ -14,6 +14,7 @@
 #ifndef __ASSEMBLY__
 
 #include <linux/compiler.h>
+#include <linux/kcsan-checks.h>
 #include <asm/rwonce.h>
 
 #ifndef nop
@@ -62,15 +63,15 @@
 #ifdef CONFIG_SMP
 
 #ifndef smp_mb
-#define smp_mb()       __smp_mb()
+#define smp_mb()       do { kcsan_mb(); __smp_mb(); } while (0)
 #endif
 
 #ifndef smp_rmb
-#define smp_rmb()      __smp_rmb()
+#define smp_rmb()      do { kcsan_rmb(); __smp_rmb(); } while (0)
 #endif
 
 #ifndef smp_wmb
-#define smp_wmb()      __smp_wmb()
+#define smp_wmb()      do { kcsan_wmb(); __smp_wmb(); } while (0)
 #endif
 
 #else  /* !CONFIG_SMP */
@@ -123,19 +124,19 @@ do {                                                                      \
 #ifdef CONFIG_SMP
 
 #ifndef smp_store_mb
-#define smp_store_mb(var, value)  __smp_store_mb(var, value)
+#define smp_store_mb(var, value)  do { kcsan_mb(); __smp_store_mb(var, value); } while (0)
 #endif
 
 #ifndef smp_mb__before_atomic
-#define smp_mb__before_atomic()        __smp_mb__before_atomic()
+#define smp_mb__before_atomic()        do { kcsan_mb(); __smp_mb__before_atomic(); } while (0)
 #endif
 
 #ifndef smp_mb__after_atomic
-#define smp_mb__after_atomic() __smp_mb__after_atomic()
+#define smp_mb__after_atomic() do { kcsan_mb(); __smp_mb__after_atomic(); } while (0)
 #endif
 
 #ifndef smp_store_release
-#define smp_store_release(p, v) __smp_store_release(p, v)
+#define smp_store_release(p, v) do { kcsan_release(); __smp_store_release(p, v); } while (0)
 #endif
 
 #ifndef smp_load_acquire
@@ -178,13 +179,13 @@ do {                                                                      \
 #endif /* CONFIG_SMP */
 
 /* Barriers for virtual machine guests when talking to an SMP host */
-#define virt_mb() __smp_mb()
-#define virt_rmb() __smp_rmb()
-#define virt_wmb() __smp_wmb()
-#define virt_store_mb(var, value) __smp_store_mb(var, value)
-#define virt_mb__before_atomic() __smp_mb__before_atomic()
-#define virt_mb__after_atomic()        __smp_mb__after_atomic()
-#define virt_store_release(p, v) __smp_store_release(p, v)
+#define virt_mb() do { kcsan_mb(); __smp_mb(); } while (0)
+#define virt_rmb() do { kcsan_rmb(); __smp_rmb(); } while (0)
+#define virt_wmb() do { kcsan_wmb(); __smp_wmb(); } while (0)
+#define virt_store_mb(var, value) do { kcsan_mb(); __smp_store_mb(var, value); } while (0)
+#define virt_mb__before_atomic() do { kcsan_mb(); __smp_mb__before_atomic(); } while (0)
+#define virt_mb__after_atomic()        do { kcsan_mb(); __smp_mb__after_atomic(); } while (0)
+#define virt_store_release(p, v) do { kcsan_release(); __smp_store_release(p, v); } while (0)
 #define virt_load_acquire(p) __smp_load_acquire(p)
 
 /**

diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h
index b4e5ca2..5c0c517 100644 (file)
--- a/include/linux/spinlock.h
+++ b/include/linux/spinlock.h
@@ -171,7 +171,7 @@ do {                                                                        \
  * Architectures that can implement ACQUIRE better need to take care.
  */
 #ifndef smp_mb__after_spinlock
-#define smp_mb__after_spinlock()       do { } while (0)
+#define smp_mb__after_spinlock()       kcsan_mb()
 #endif
 
 #ifdef CONFIG_DEBUG_SPINLOCK