x86: move switch_to macro to system.h

This patch moves the switch_to() macro to system.h

As those macros are fundamentally different between i386 and x86_64,
they are enclosed around an ifdef.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/include/asm-x86/system.h b/include/asm-x86/system.h
index 4c15eb1..ba3403f 100644 (file)
--- a/include/asm-x86/system.h
+++ b/include/asm-x86/system.h
@@ -6,8 +6,69 @@
 #include <linux/kernel.h>
 
 #ifdef CONFIG_X86_32
+#define AT_VECTOR_SIZE_ARCH 2 /* entries in ARCH_DLINFO */
+
+struct task_struct; /* one of the stranger aspects of C forward declarations */
+extern struct task_struct *FASTCALL(__switch_to(struct task_struct *prev,
+                                               struct task_struct *next));
+
+/*
+ * Saving eflags is important. It switches not only IOPL between tasks,
+ * it also protects other tasks from NT leaking through sysenter etc.
+ */
+#define switch_to(prev, next, last) do {                               \
+       unsigned long esi, edi;                                         \
+       asm volatile("pushfl\n\t"               /* Save flags */        \
+                    "pushl %%ebp\n\t"                                  \
+                    "movl %%esp,%0\n\t"        /* save ESP */          \
+                    "movl %5,%%esp\n\t"        /* restore ESP */       \
+                    "movl $1f,%1\n\t"          /* save EIP */          \
+                    "pushl %6\n\t"             /* restore EIP */       \
+                    "jmp __switch_to\n"                                \
+                    "1:\t"                                             \
+                    "popl %%ebp\n\t"                                   \
+                    "popfl"                                            \
+                    :"=m" (prev->thread.sp), "=m" (prev->thread.ip),   \
+                     "=a" (last), "=S" (esi), "=D" (edi)               \
+                    :"m" (next->thread.sp), "m" (next->thread.ip),     \
+                     "2" (prev), "d" (next));                          \
+} while (0)
+
 # include "system_32.h"
 #else
+#define __SAVE(reg, offset) "movq %%" #reg ",(14-" #offset ")*8(%%rsp)\n\t"
+#define __RESTORE(reg, offset) "movq (14-" #offset ")*8(%%rsp),%%" #reg "\n\t"
+
+/* frame pointer must be last for get_wchan */
+#define SAVE_CONTEXT    "pushf ; pushq %%rbp ; movq %%rsi,%%rbp\n\t"
+#define RESTORE_CONTEXT "movq %%rbp,%%rsi ; popq %%rbp ; popf\t"
+
+#define __EXTRA_CLOBBER  \
+       , "rcx", "rbx", "rdx", "r8", "r9", "r10", "r11", \
+         "r12", "r13", "r14", "r15"
+
+/* Save restore flags to clear handle leaking NT */
+#define switch_to(prev, next, last) \
+       asm volatile(SAVE_CONTEXT                                         \
+            "movq %%rsp,%P[threadrsp](%[prev])\n\t" /* save RSP */       \
+            "movq %P[threadrsp](%[next]),%%rsp\n\t" /* restore RSP */    \
+            "call __switch_to\n\t"                                       \
+            ".globl thread_return\n"                                     \
+            "thread_return:\n\t"                                         \
+            "movq %%gs:%P[pda_pcurrent],%%rsi\n\t"                       \
+            "movq %P[thread_info](%%rsi),%%r8\n\t"                       \
+            LOCK_PREFIX "btr  %[tif_fork],%P[ti_flags](%%r8)\n\t"        \
+            "movq %%rax,%%rdi\n\t"                                       \
+            "jc   ret_from_fork\n\t"                                     \
+            RESTORE_CONTEXT                                              \
+            : "=a" (last)                                                \
+            : [next] "S" (next), [prev] "D" (prev),                      \
+              [threadrsp] "i" (offsetof(struct task_struct, thread.sp)), \
+              [ti_flags] "i" (offsetof(struct thread_info, flags)),      \
+              [tif_fork] "i" (TIF_FORK),                                 \
+              [thread_info] "i" (offsetof(struct task_struct, stack)),   \
+              [pda_pcurrent] "i" (offsetof(struct x8664_pda, pcurrent))  \
+            : "memory", "cc" __EXTRA_CLOBBER)
 # include "system_64.h"
 #endif
 

diff --git a/include/asm-x86/system_32.h b/include/asm-x86/system_32.h
index 7da0716..83af464 100644 (file)
--- a/include/asm-x86/system_32.h
+++ b/include/asm-x86/system_32.h
@@ -5,37 +5,6 @@
 #include <asm/cpufeature.h>
 #include <asm/cmpxchg.h>
 
-#ifdef __KERNEL__
-#define AT_VECTOR_SIZE_ARCH 2 /* entries in ARCH_DLINFO */
-
-struct task_struct;    /* one of the stranger aspects of C forward declarations.. */
-extern struct task_struct * FASTCALL(__switch_to(struct task_struct *prev, struct task_struct *next));
-
-/*
- * Saving eflags is important. It switches not only IOPL between tasks,
- * it also protects other tasks from NT leaking through sysenter etc.
- */
-#define switch_to(prev,next,last) do {                                 \
-       unsigned long esi,edi;                                          \
-       asm volatile("pushfl\n\t"               /* Save flags */        \
-                    "pushl %%ebp\n\t"                                  \
-                    "movl %%esp,%0\n\t"        /* save ESP */          \
-                    "movl %5,%%esp\n\t"        /* restore ESP */       \
-                    "movl $1f,%1\n\t"          /* save EIP */          \
-                    "pushl %6\n\t"             /* restore EIP */       \
-                    "jmp __switch_to\n"                                \
-                    "1:\t"                                             \
-                    "popl %%ebp\n\t"                                   \
-                    "popfl"                                            \
-                    :"=m" (prev->thread.sp),"=m" (prev->thread.ip),    \
-                     "=a" (last),"=S" (esi),"=D" (edi)                 \
-                    :"m" (next->thread.sp),"m" (next->thread.ip),      \
-                     "2" (prev), "d" (next));                          \
-} while (0)
-
-#endif /* __KERNEL__ */
-
-
 #include <linux/irqflags.h>
 
 /*

diff --git a/include/asm-x86/system_64.h b/include/asm-x86/system_64.h
index 9def35e..97fa251 100644 (file)
--- a/include/asm-x86/system_64.h
+++ b/include/asm-x86/system_64.h
@@ -4,49 +4,6 @@
 #include <asm/segment.h>
 #include <asm/cmpxchg.h>
 
-#ifdef __KERNEL__
-
-/* entries in ARCH_DLINFO: */
-#ifdef CONFIG_IA32_EMULATION
-# define AT_VECTOR_SIZE_ARCH 2
-#else
-# define AT_VECTOR_SIZE_ARCH 1
-#endif
-
-#define __SAVE(reg,offset) "movq %%" #reg ",(14-" #offset ")*8(%%rsp)\n\t"
-#define __RESTORE(reg,offset) "movq (14-" #offset ")*8(%%rsp),%%" #reg "\n\t"
-
-/* frame pointer must be last for get_wchan */
-#define SAVE_CONTEXT    "pushf ; pushq %%rbp ; movq %%rsi,%%rbp\n\t"
-#define RESTORE_CONTEXT "movq %%rbp,%%rsi ; popq %%rbp ; popf\t"
-
-#define __EXTRA_CLOBBER  \
-       ,"rcx","rbx","rdx","r8","r9","r10","r11","r12","r13","r14","r15"
-
-/* Save restore flags to clear handle leaking NT */
-#define switch_to(prev,next,last) \
-       asm volatile(SAVE_CONTEXT                                                   \
-                    "movq %%rsp,%P[threadrsp](%[prev])\n\t" /* save RSP */       \
-                    "movq %P[threadrsp](%[next]),%%rsp\n\t" /* restore RSP */    \
-                    "call __switch_to\n\t"                                       \
-                    ".globl thread_return\n"                                   \
-                    "thread_return:\n\t"                                           \
-                    "movq %%gs:%P[pda_pcurrent],%%rsi\n\t"                       \
-                    "movq %P[thread_info](%%rsi),%%r8\n\t"                       \
-                    LOCK_PREFIX "btr  %[tif_fork],%P[ti_flags](%%r8)\n\t"        \
-                    "movq %%rax,%%rdi\n\t"                                       \
-                    "jc   ret_from_fork\n\t"                                     \
-                    RESTORE_CONTEXT                                                \
-                    : "=a" (last)                                                \
-                    : [next] "S" (next), [prev] "D" (prev),                      \
-                      [threadrsp] "i" (offsetof(struct task_struct, thread.sp)), \
-                      [ti_flags] "i" (offsetof(struct thread_info, flags)),\
-                      [tif_fork] "i" (TIF_FORK),                         \
-                      [thread_info] "i" (offsetof(struct task_struct, stack)), \
-                      [pda_pcurrent] "i" (offsetof(struct x8664_pda, pcurrent))   \
-                    : "memory", "cc" __EXTRA_CLOBBER)
-    
-#endif /* __KERNEL__ */
 
 static inline unsigned long read_cr8(void)
 {