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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/metag/oprofile/backtrace.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/metag/oprofile/backtrace.c')
-rw-r--r--kernel/arch/metag/oprofile/backtrace.c63
1 files changed, 63 insertions, 0 deletions
diff --git a/kernel/arch/metag/oprofile/backtrace.c b/kernel/arch/metag/oprofile/backtrace.c
new file mode 100644
index 000000000..7cc3f37cb
--- /dev/null
+++ b/kernel/arch/metag/oprofile/backtrace.c
@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2010-2013 Imagination Technologies Ltd.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/oprofile.h>
+#include <linux/uaccess.h>
+#include <asm/processor.h>
+#include <asm/stacktrace.h>
+
+#include "backtrace.h"
+
+static void user_backtrace_fp(unsigned long __user *fp, unsigned int depth)
+{
+ while (depth-- && access_ok(VERIFY_READ, fp, 8)) {
+ unsigned long addr;
+ unsigned long __user *fpnew;
+ if (__copy_from_user_inatomic(&addr, fp + 1, sizeof(addr)))
+ break;
+ addr -= 4;
+
+ oprofile_add_trace(addr);
+
+ /* stack grows up, so frame pointers must decrease */
+ if (__copy_from_user_inatomic(&fpnew, fp + 0, sizeof(fpnew)))
+ break;
+ if (fpnew >= fp)
+ break;
+ fp = fpnew;
+ }
+}
+
+static int kernel_backtrace_frame(struct stackframe *frame, void *data)
+{
+ unsigned int *depth = data;
+
+ oprofile_add_trace(frame->pc);
+
+ /* decrement depth and stop if we reach 0 */
+ if ((*depth)-- == 0)
+ return 1;
+
+ /* otherwise onto the next frame */
+ return 0;
+}
+
+void metag_backtrace(struct pt_regs * const regs, unsigned int depth)
+{
+ if (user_mode(regs)) {
+ unsigned long *fp = (unsigned long *)regs->ctx.AX[1].U0;
+ user_backtrace_fp((unsigned long __user __force *)fp, depth);
+ } else {
+ struct stackframe frame;
+ frame.fp = regs->ctx.AX[1].U0; /* A0FrP */
+ frame.sp = user_stack_pointer(regs); /* A0StP */
+ frame.lr = 0; /* from stack */
+ frame.pc = regs->ctx.CurrPC; /* PC */
+ walk_stackframe(&frame, &kernel_backtrace_frame, &depth);
+ }
+}