patch-2.3.27 linux/arch/i386/kernel/process.c

• Lines: 38
• Date: Mon Nov 8 10:19:19 1999
• Orig file: v2.3.26/linux/arch/i386/kernel/process.c
• Orig date: Mon Nov 1 13:56:26 1999

diff -u --recursive --new-file v2.3.26/linux/arch/i386/kernel/process.c linux/arch/i386/kernel/process.c
@@ -685,3 +685,37 @@
 	unlock_kernel();
 	return error;
 }
+
+/*
+ * These bracket the sleeping functions..
+ */
+extern void scheduling_functions_start_here(void);
+extern void scheduling_functions_end_here(void);
+#define first_sched	((unsigned long) scheduling_functions_start_here)
+#define last_sched	((unsigned long) scheduling_functions_end_here)
+
+unsigned long get_wchan(struct task_struct *p)
+{
+	unsigned long ebp, esp, eip;
+	unsigned long stack_page;
+	int count = 0;
+	if (!p || p == current || p->state == TASK_RUNNING)
+		return 0;
+	stack_page = (unsigned long)p;
+	esp = p->thread.esp;
+	if (!stack_page || esp < stack_page || esp > 8188+stack_page)
+		return 0;
+	/* include/asm-i386/system.h:switch_to() pushes ebp last. */
+	ebp = *(unsigned long *) esp;
+	do {
+		if (ebp < stack_page || ebp > 8184+stack_page)
+			return 0;
+		eip = *(unsigned long *) (ebp+4);
+		if (eip < first_sched || eip >= last_sched)
+			return eip;
+		ebp = *(unsigned long *) ebp;
+	} while (count++ < 16);
+	return 0;
+}
+#undef last_sched
+#undef first_sched