Changeset 1066041 in mainline for kernel/generic/include/preemption.h

Timestamp:

2012-07-11T07:58:03Z (12 years ago)

Author:

Adam Hraska <adam.hraska+hos@…>

Branches:

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

Children:

935e28c

Parents:

b68ae24

Message:

preemption_disable: Turned functions into macros. Moved THREAD, AS, TASK, CPU into thread.h, as.h, task.h, cpu.h to fix the include hell that ensued.

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);
-extern void preemption_enable_noresched(void);
-extern void preemption_enabled_scheduler(void);
+#include <arch.h>
+#include <compiler/barrier.h>
+#include <debug.h>
+
+#define PREEMPTION_INC         (1 << 1)
+#define PREEMPTION_NEEDED_FLAG (1 << 0)
+#define PREEMPTION_NEEDED      (THE->preemption & PREEMPTION_NEEDED_FLAG)
+#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 and reschedules if out time slice already elapsed.*/
+#define preemption_enable() \
+        do { \
+                preemption_enable_noresched(); \
+                \
+                if (PREEMPTION_ENABLED && PREEMPTION_NEEDED) { \
+                        preemption_enabled_scheduler(); \
+                } \
+        } while (0)
+
+/** Restores preemption but never reschedules. */
+#define preemption_enable_noresched() \
+        do { \
+                ASSERT(PREEMPTION_DISABLED); \
+                compiler_barrier(); \
+                THE->preemption -= PREEMPTION_INC; \
+        } while (0)
 
 
+extern void preemption_enabled_scheduler(void);
+extern void preemption_set_needed(void);
+extern void preemption_clear_needed(void);
 
 #endif