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Diffstat (limited to 'include/asm-x86_64/alternative.h')
-rw-r--r--include/asm-x86_64/alternative.h68
1 files changed, 35 insertions, 33 deletions
diff --git a/include/asm-x86_64/alternative.h b/include/asm-x86_64/alternative.h
index a0942764076..eea7aecfac7 100644
--- a/include/asm-x86_64/alternative.h
+++ b/include/asm-x86_64/alternative.h
@@ -5,6 +5,41 @@
#include <linux/types.h>
#include <linux/stddef.h>
+
+/*
+ * Alternative inline assembly for SMP.
+ *
+ * The LOCK_PREFIX macro defined here replaces the LOCK and
+ * LOCK_PREFIX macros used everywhere in the source tree.
+ *
+ * SMP alternatives use the same data structures as the other
+ * alternatives and the X86_FEATURE_UP flag to indicate the case of a
+ * UP system running a SMP kernel. The existing apply_alternatives()
+ * works fine for patching a SMP kernel for UP.
+ *
+ * The SMP alternative tables can be kept after boot and contain both
+ * UP and SMP versions of the instructions to allow switching back to
+ * SMP at runtime, when hotplugging in a new CPU, which is especially
+ * useful in virtualized environments.
+ *
+ * The very common lock prefix is handled as special case in a
+ * separate table which is a pure address list without replacement ptr
+ * and size information. That keeps the table sizes small.
+ */
+
+#ifdef CONFIG_SMP
+#define LOCK_PREFIX \
+ ".section .smp_locks,\"a\"\n" \
+ " .align 8\n" \
+ " .quad 661f\n" /* address */ \
+ ".previous\n" \
+ "661:\n\tlock; "
+
+#else /* ! CONFIG_SMP */
+#define LOCK_PREFIX ""
+#endif
+
+/* This must be included *after* the definition of LOCK_PREFIX */
#include <asm/cpufeature.h>
struct alt_instr {
@@ -108,39 +143,6 @@ static inline void alternatives_smp_switch(int smp) {}
*/
#define ASM_OUTPUT2(a, b) a, b
-/*
- * Alternative inline assembly for SMP.
- *
- * The LOCK_PREFIX macro defined here replaces the LOCK and
- * LOCK_PREFIX macros used everywhere in the source tree.
- *
- * SMP alternatives use the same data structures as the other
- * alternatives and the X86_FEATURE_UP flag to indicate the case of a
- * UP system running a SMP kernel. The existing apply_alternatives()
- * works fine for patching a SMP kernel for UP.
- *
- * The SMP alternative tables can be kept after boot and contain both
- * UP and SMP versions of the instructions to allow switching back to
- * SMP at runtime, when hotplugging in a new CPU, which is especially
- * useful in virtualized environments.
- *
- * The very common lock prefix is handled as special case in a
- * separate table which is a pure address list without replacement ptr
- * and size information. That keeps the table sizes small.
- */
-
-#ifdef CONFIG_SMP
-#define LOCK_PREFIX \
- ".section .smp_locks,\"a\"\n" \
- " .align 8\n" \
- " .quad 661f\n" /* address */ \
- ".previous\n" \
- "661:\n\tlock; "
-
-#else /* ! CONFIG_SMP */
-#define LOCK_PREFIX ""
-#endif
-
struct paravirt_patch;
#ifdef CONFIG_PARAVIRT
void apply_paravirt(struct paravirt_patch *start, struct paravirt_patch *end);