ARM: smp_on_up: move inline asm ALT_SMP patching macro out of spinlock.h

Patching UP/SMP alternatives inside inline assembly blocks is useful
outside of the spinlock implementation, where it is used for sev and wfe.

This patch lifts the macro into processor.h and gives it a scarier name
to (a) avoid conflicts in the global namespace and (b) to try and deter
its usage unless you "know what you're doing". The W macro for generating
wide instructions when targetting Thumb-2 is also made available under
the name WASM, to reduce the potential for conflicts with other headers.

Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>

diff --git a/arch/arm/include/asm/processor.h b/arch/arm/include/asm/processor.h
index 514a989cbd4b4084aa8e7d560eaf8f64277436a1..26164c92fa308102de2d16965da706fa7a4bb2d7 100644 (file)
--- a/arch/arm/include/asm/processor.h
+++ b/arch/arm/include/asm/processor.h
@@ -22,6 +22,7 @@
 #include <asm/hw_breakpoint.h>
 #include <asm/ptrace.h>
 #include <asm/types.h>
+#include <asm/unified.h>
 
 #ifdef __KERNEL__
 #define STACK_TOP      ((current->personality & ADDR_LIMIT_32BIT) ? \
@@ -87,6 +88,17 @@ unsigned long get_wchan(struct task_struct *p);
 #define KSTK_EIP(tsk)  task_pt_regs(tsk)->ARM_pc
 #define KSTK_ESP(tsk)  task_pt_regs(tsk)->ARM_sp
 
+#ifdef CONFIG_SMP
+#define __ALT_SMP_ASM(smp, up)                                         \
+       "9998:  " smp "\n"                                              \
+       "       .pushsection \".alt.smp.init\", \"a\"\n"                \
+       "       .long   9998b\n"                                        \
+       "       " up "\n"                                               \
+       "       .popsection\n"
+#else
+#define __ALT_SMP_ASM(smp, up) up
+#endif
+
 /*
  * Prefetching support - only ARMv5.
  */

diff --git a/arch/arm/include/asm/spinlock.h b/arch/arm/include/asm/spinlock.h
index 4f2c28060c9aa227c47e73ac6557c45add91128f..e1ce4523091315590b75e1beed55076931c94eb0 100644 (file)
--- a/arch/arm/include/asm/spinlock.h
+++ b/arch/arm/include/asm/spinlock.h
@@ -11,15 +11,7 @@
  * sev and wfe are ARMv6K extensions.  Uniprocessor ARMv6 may not have the K
  * extensions, so when running on UP, we have to patch these instructions away.
  */
-#define ALT_SMP(smp, up)                                       \
-       "9998:  " smp "\n"                                      \
-       "       .pushsection \".alt.smp.init\", \"a\"\n"        \
-       "       .long   9998b\n"                                \
-       "       " up "\n"                                       \
-       "       .popsection\n"
-
 #ifdef CONFIG_THUMB2_KERNEL
-#define SEV            ALT_SMP("sev.w", "nop.w")
 /*
  * For Thumb-2, special care is needed to ensure that the conditional WFE
  * instruction really does assemble to exactly 4 bytes (as required by
@@ -31,17 +23,18 @@
  * the assembler won't change IT instructions which are explicitly present
  * in the input.
  */
-#define WFE(cond)      ALT_SMP(                \
+#define WFE(cond)      __ALT_SMP_ASM(          \
        "it " cond "\n\t"                       \
        "wfe" cond ".n",                        \
                                                \
        "nop.w"                                 \
 )
 #else
-#define SEV            ALT_SMP("sev", "nop")
-#define WFE(cond)      ALT_SMP("wfe" cond, "nop")
+#define WFE(cond)      __ALT_SMP_ASM("wfe" cond, "nop")
 #endif
 
+#define SEV            __ALT_SMP_ASM(WASM(sev), WASM(nop))
+
 static inline void dsb_sev(void)
 {
 #if __LINUX_ARM_ARCH__ >= 7

diff --git a/arch/arm/include/asm/unified.h b/arch/arm/include/asm/unified.h
index f5989f46b4d2d450f18b24faa946de750394ec13..b88beaba6b4a5cf9c0ccded73723c4ea41539167 100644 (file)
--- a/arch/arm/include/asm/unified.h
+++ b/arch/arm/include/asm/unified.h
@@ -38,6 +38,8 @@
 #ifdef __ASSEMBLY__
 #define W(instr)       instr.w
 #define BSYM(sym)      sym + 1
+#else
+#define WASM(instr)    #instr ".w"
 #endif
 
 #else  /* !CONFIG_THUMB2_KERNEL */
@@ -50,6 +52,8 @@
 #ifdef __ASSEMBLY__
 #define W(instr)       instr
 #define BSYM(sym)      sym
+#else
+#define WASM(instr)    #instr
 #endif
 
 #endif /* CONFIG_THUMB2_KERNEL */