This also removes an inconsistency in that x86-64''s __save_flags() had
a memory clobber, while x86_32''s didn''t.
It further adds type checking since blindly using {pop,push}{l,q} on a
memory operand of unknown size bares the risk of corrupting other data.
Finally, it eliminates the redundant (with local_irq_restore())
__restore_flags() macro and renames __save_flags() to
local_save_flags(), making the naming consistent with Linux (again?).
Signed-off-by: Jan Beulich <jbeulich@novell.com>
--- 2008-11-20.orig/xen/include/asm-x86/system.h 2008-04-30 11:54:44.000000000
+0200
+++ 2008-11-20/xen/include/asm-x86/system.h 2008-12-11 09:51:06.000000000 +0100
@@ -1,8 +1,7 @@
#ifndef __ASM_SYSTEM_H
#define __ASM_SYSTEM_H
-#include <xen/config.h>
-#include <xen/types.h>
+#include <xen/lib.h>
#include <asm/bitops.h>
#define read_segment_register(name) \
@@ -171,10 +170,27 @@ static always_inline unsigned long __cmp
/* used when interrupts are already enabled or to shutdown the processor */
#define halt() asm volatile ( "hlt" : : : "memory"
)
+#define local_save_flags(x) \
+({ \
+ BUILD_BUG_ON(sizeof(x) != sizeof(long)); \
+ asm volatile ( "pushf" __OS " ; pop" __OS "
%0" : "=g" (x)); \
+})
+#define local_irq_save(x) \
+({ \
+ local_save_flags(x); \
+ local_irq_disable(); \
+})
+#define local_irq_restore(x) \
+({ \
+ BUILD_BUG_ON(sizeof(x) != sizeof(long)); \
+ asm volatile ( "push" __OS " %0 ; popf" __OS
\
+ : : "g" (x) : "memory", "cc"
); \
+})
+
static inline int local_irq_is_enabled(void)
{
unsigned long flags;
- __save_flags(flags);
+ local_save_flags(flags);
return !!(flags & (1<<9)); /* EFLAGS_IF */
}
--- 2008-11-20.orig/xen/include/asm-x86/x86_32/system.h 2007-11-26
16:57:03.000000000 +0100
+++ 2008-11-20/xen/include/asm-x86/x86_32/system.h 2008-12-11 09:33:14.000000000
+0100
@@ -101,14 +101,4 @@ static inline void atomic_write64(uint64
#define mb() \
asm volatile ( "lock; addl $0,0(%%esp)" : : : "memory"
)
-#define __save_flags(x) \
- asm volatile ( "pushfl ; popl %0" : "=g" (x) : )
-#define __restore_flags(x) \
- asm volatile ( "pushl %0 ; popfl" : : "g" (x) :
"memory", "cc" )
-
-#define local_irq_save(x) \
- asm volatile ( "pushfl ; popl %0 ; cli" : "=g" (x) : :
"memory" )
-#define local_irq_restore(x) \
- __restore_flags(x)
-
#endif /* __X86_32_SYSTEM_H__ */
--- 2008-11-20.orig/xen/include/asm-x86/x86_64/system.h 2007-11-26
16:57:03.000000000 +0100
+++ 2008-11-20/xen/include/asm-x86/x86_64/system.h 2008-12-11 09:33:40.000000000
+0100
@@ -55,14 +55,4 @@ static inline void atomic_write64(uint64
#define mb() \
asm volatile ( "mfence" : : : "memory" )
-#define __save_flags(x) \
- asm volatile ( "pushfq ; popq %q0" : "=g" (x) :
:"memory" )
-#define __restore_flags(x) \
- asm volatile ( "pushq %0 ; popfq" : : "g" (x) :
"memory", "cc" )
-
-#define local_irq_save(x) \
- asm volatile ( "pushfq ; popq %0 ; cli" : "=g" (x) : :
"memory" )
-#define local_irq_restore(x) \
- __restore_flags(x)
-
#endif /* __X86_64_SYSTEM_H__ */
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