Changeset b1c57a8 in mainline for kernel/generic/include/preemption.h

Timestamp:

2014-10-09T15:03:55Z (10 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

e367939c

Parents:

21799398 (diff), 207e8880 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge from lp:~adam-hraska+lp/helenos/rcu/.

Only merge from the feature branch and resolve all conflicts.

File:

• kernel/generic/include/preemption.h (modified) (1 diff)

kernel/generic/include/preemption.h

@@ -36 +36 @@
 #define KERN_PREEMPTION_H_
 
-extern void preemption_disable(void);
-extern void preemption_enable(void);
+#include <arch.h>
+#include <compiler/barrier.h>
+#include <debug.h>
+
+#define PREEMPTION_INC         (1 << 0)
+#define PREEMPTION_DISABLED    (PREEMPTION_INC <= THE->preemption)
+#define PREEMPTION_ENABLED     (!PREEMPTION_DISABLED)
+
+/** Increment preemption disabled counter. */
+#define preemption_disable() \
+        do { \
+                THE->preemption += PREEMPTION_INC; \
+                compiler_barrier(); \
+        } while (0)
+
+/** Restores preemption but never reschedules. */
+#define preemption_enable() \
+        do { \
+                ASSERT(PREEMPTION_DISABLED); \
+                compiler_barrier(); \
+                THE->preemption -= PREEMPTION_INC; \
+        } while (0)
+
 
 #endif