sched/x86: Add 'struct inactive_task_frame' to better document the sleeping task stack frame
Add 'struct inactive_task_frame', which defines the layout of the stack for
a sleeping process. For now, the only defined field is the BP register
(frame pointer).
Signed-off-by: Brian Gerst <brgerst@gmail.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1471106302-10159-4-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/arch/x86/include/asm/stacktrace.h b/arch/x86/include/asm/stacktrace.h
index 0944218..7646fb2 100644
--- a/arch/x86/include/asm/stacktrace.h
+++ b/arch/x86/include/asm/stacktrace.h
@@ -8,6 +8,7 @@
#include <linux/uaccess.h>
#include <linux/ptrace.h>
+#include <asm/switch_to.h>
extern int kstack_depth_to_print;
@@ -70,8 +71,7 @@
return bp;
}
- /* bp is the last reg pushed by switch_to */
- return *(unsigned long *)task->thread.sp;
+ return ((struct inactive_task_frame *)task->thread.sp)->bp;
}
#else
static inline unsigned long