Changeset bea6233 in mainline for kernel/arch/amd64/include/arch/asm.h

Timestamp:

2023-02-26T15:27:13Z (14 months ago)

Author:

Jiří Zárevúcky <zarevucky.jiri@…>

Branches:

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

Children:

7cf5ddb

Parents:

deed510

git-author:

Jiří Zárevúcky <zarevucky.jiri@…> (2023-02-26 15:18:02)

git-committer:

Jiří Zárevúcky <zarevucky.jiri@…> (2023-02-26 15:27:13)

Message:

Replace cpu_sleep() with cpu_interruptible_sleep()

The new function combines interrupt reenabling with sleep,
so that a platform can implement this sequence atomically.
This is currently done only on ia32 and amd64.

File:

• kernel/arch/amd64/include/arch/asm.h (modified) (1 diff)

kernel/arch/amd64/include/arch/asm.h

@@ -43 +43 @@
 #define IO_SPACE_BOUNDARY       ((void *) (64 * 1024))
 
-_NO_TRACE static inline void cpu_sleep(void)
-{
-        asm volatile (
+/** Enables interrupts and blocks until an interrupt arrives,
+ * atomically if possible on target architecture.
+ * Disables interrupts again before returning to caller.
+ */
+_NO_TRACE static inline void cpu_interruptible_sleep()
+{
+        /*
+         * On x86, "sti" enables interrupts after the next instruction.
+         * Therefore, this sequence is guaranteed to be atomic.
+         */
+        asm volatile (
+            "sti\n"
             "hlt\n"
+            "cli\n"
         );
 }