Merge branch 'akpm-current/current'

[deliverable/linux.git] / arch / x86 / kernel / process.c

diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 857a686eba5eed5b2d6981be60791288733d66da..5308fb39e3040dae0075e96c5bf78428806fa55c 100644 (file)
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -32,6 +32,7 @@
 #include <asm/tlbflush.h>
 #include <asm/mce.h>
 #include <asm/vm86.h>
+#include <asm/switch_to.h>
 
 /*
  * per-CPU TSS segments. Threads are completely 'soft' on Linux,
@@ -511,6 +512,17 @@ unsigned long arch_randomize_brk(struct mm_struct *mm)
        return randomize_page(mm->brk, 0x02000000);
 }
 
+/*
+ * Return saved PC of a blocked thread.
+ * What is this good for? it will be always the scheduler or ret_from_fork.
+ */
+unsigned long thread_saved_pc(struct task_struct *tsk)
+{
+       struct inactive_task_frame *frame =
+               (struct inactive_task_frame *) READ_ONCE(tsk->thread.sp);
+       return READ_ONCE_NOCHECK(frame->ret_addr);
+}
+
 /*
  * Called from fs/proc with a reference on @p to find the function
  * which called into schedule(). This needs to be done carefully
@@ -555,7 +567,7 @@ unsigned long get_wchan(struct task_struct *p)
        if (sp < bottom || sp > top)
                return 0;
 
-       fp = READ_ONCE_NOCHECK(*(unsigned long *)sp);
+       fp = READ_ONCE_NOCHECK(((struct inactive_task_frame *)sp)->bp);
        do {
                if (fp < bottom || fp > top)
                        return 0;