Changeset 82d56184 in mainline for kernel/arch/ia64/include/asm.h

Timestamp:

2011-06-01T21:05:19Z (13 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

5cac9cd

Parents:

682cfceb (diff), 5d1b3aa (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 mainline changes.

File:

• kernel/arch/ia64/include/asm.h (modified) (1 diff)

kernel/arch/ia64/include/asm.h

@@ -122 +122 @@
 }
 
-/** Return base address of current stack
- *
- * Return the base address of the current stack.
- * The stack is assumed to be STACK_SIZE long.
- * The stack must start on page boundary.
- *
+/** Return base address of current memory stack.
+ *
+ * The memory stack is assumed to be STACK_SIZE / 2 long. Note that there is
+ * also the RSE stack, which takes up the upper half of STACK_SIZE.
+ * The memory stack must start on page boundary.
  */
 NO_TRACE static inline uintptr_t get_stack_base(void)
 {
-        uint64_t v;
-        
-        /*
-         * I'm not sure why but this code inlines badly
-         * in scheduler, resulting in THE shifting about
-         * 16B and causing kernel panic.
-         *
-         * asm volatile (
-         *     "and %[value] = %[mask], r12"
-         *     : [value] "=r" (v)
-         *     : [mask] "r" (~(STACK_SIZE - 1))
-         * );
-         * return v;
-         *
-         * The following code has the same semantics but
-         * inlines correctly.
-         *
-         */
+        uint64_t value;
         
         asm volatile (
                 "mov %[value] = r12"
-                : [value] "=r" (v)
-        );
-        
-        return (v & (~(STACK_SIZE - 1)));
+                : [value] "=r" (value)
+        );
+        
+        return (value & (~(STACK_SIZE / 2 - 1)));
 }