[PATCH] i386: cleanups to help using per-cpu variables from asm
This patch does a few small cleanups:
- use PER_CPU_NAME to generate the names of per-cpu variables
- use lea to add the per_cpu offset in PER_CPU(), because it doesn't
affect condition flags
- add PER_CPU_VAR which allows direct access to pre-cpu variables
with the %fs: prefix on SMP.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
diff --git a/include/asm-i386/percpu.h b/include/asm-i386/percpu.h
index c5f12f0..cdcb63d 100644
--- a/include/asm-i386/percpu.h
+++ b/include/asm-i386/percpu.h
@@ -16,12 +16,14 @@
* PER_CPU(cpu_gdt_descr, %ebx)
*/
#ifdef CONFIG_SMP
-#define PER_CPU(var, reg) \
- movl %fs:per_cpu__this_cpu_off, reg; \
- addl $per_cpu__##var, reg
+#define PER_CPU(var, reg) \
+ movl %fs:per_cpu__##this_cpu_off, reg; \
+ lea per_cpu__##var(reg), reg
+#define PER_CPU_VAR(var) %fs:per_cpu__##var
#else /* ! SMP */
-#define PER_CPU(var, reg) \
- movl $per_cpu__##var, reg;
+#define PER_CPU(var, reg) \
+ movl $per_cpu__##var, reg
+#define PER_CPU_VAR(var) per_cpu__##var
#endif /* SMP */
#else /* ...!ASSEMBLY */