add some functions related to migration into kernel/process.h

... and also add include guard to arch/x86/kernel/include/signal.h

arch/x86/kernel/cpu.c

@@ -21,6 +21,7 @@
 #include <cpulocal.h>
 #include <march.h>
 #include <signal.h>
+#include <process.h>
 
 #define LAPIC_ID            0x020
 #define LAPIC_TIMER         0x320

arch/x86/kernel/include/signal.h

@@ -11,6 +11,9 @@
  *  2012/02/11 bgerofi what kind of new features have been added
  */
 
+#ifndef __HEADER_X86_COMMON_SIGNAL_H
+#define __HEADER_X86_COMMON_SIGNAL_H
+
 #define _NSIG		64
 #define _NSIG_BPW	64
 #define _NSIG_WORDS (_NSIG / _NSIG_BPW)
@@ -149,3 +152,5 @@ typedef struct siginfo {
 #define SIGSYS          31
 #define SIGUNUSED       31
 #define SIGRTMIN        32
+
+#endif /*__HEADER_X86_COMMON_SIGNAL_H*/

kernel/include/process.h

@@ -261,4 +261,7 @@ void runq_add_proc(struct process *proc, int cpu_id);
 void runq_del_proc(struct process *proc, int cpu_id);
 int sched_wakeup_process(struct process *proc, int valid_states);
 
+void sched_request_migrate(int cpu_id, struct process *proc);
+void check_need_resched(void);
+
 #endif