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-rw-r--r--arch/s390/kernel/mcount.S82
1 files changed, 82 insertions, 0 deletions
diff --git a/arch/s390/kernel/mcount.S b/arch/s390/kernel/mcount.S
new file mode 100644
index 000000000..e499370fb
--- /dev/null
+++ b/arch/s390/kernel/mcount.S
@@ -0,0 +1,82 @@
+/*
+ * Copyright IBM Corp. 2008, 2009
+ *
+ * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
+ *
+ */
+
+#include <linux/linkage.h>
+#include <asm/asm-offsets.h>
+#include <asm/ftrace.h>
+#include <asm/ptrace.h>
+
+ .section .kprobes.text, "ax"
+
+ENTRY(ftrace_stub)
+ br %r14
+
+#define STACK_FRAME_SIZE (STACK_FRAME_OVERHEAD + __PT_SIZE)
+#define STACK_PTREGS (STACK_FRAME_OVERHEAD)
+#define STACK_PTREGS_GPRS (STACK_PTREGS + __PT_GPRS)
+#define STACK_PTREGS_PSW (STACK_PTREGS + __PT_PSW)
+
+ENTRY(_mcount)
+ br %r14
+
+ENTRY(ftrace_caller)
+ .globl ftrace_regs_caller
+ .set ftrace_regs_caller,ftrace_caller
+ lgr %r1,%r15
+#ifndef CC_USING_HOTPATCH
+ aghi %r0,MCOUNT_RETURN_FIXUP
+#endif
+ aghi %r15,-STACK_FRAME_SIZE
+ stg %r1,__SF_BACKCHAIN(%r15)
+ stg %r1,(STACK_PTREGS_GPRS+15*8)(%r15)
+ stg %r0,(STACK_PTREGS_PSW+8)(%r15)
+ stmg %r2,%r14,(STACK_PTREGS_GPRS+2*8)(%r15)
+#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
+ aghik %r2,%r0,-MCOUNT_INSN_SIZE
+ lgrl %r4,function_trace_op
+ lgrl %r1,ftrace_trace_function
+#else
+ lgr %r2,%r0
+ aghi %r2,-MCOUNT_INSN_SIZE
+ larl %r4,function_trace_op
+ lg %r4,0(%r4)
+ larl %r1,ftrace_trace_function
+ lg %r1,0(%r1)
+#endif
+ lgr %r3,%r14
+ la %r5,STACK_PTREGS(%r15)
+ basr %r14,%r1
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+# The j instruction gets runtime patched to a nop instruction.
+# See ftrace_enable_ftrace_graph_caller.
+ENTRY(ftrace_graph_caller)
+ j ftrace_graph_caller_end
+ lg %r2,(STACK_PTREGS_GPRS+14*8)(%r15)
+ lg %r3,(STACK_PTREGS_PSW+8)(%r15)
+ brasl %r14,prepare_ftrace_return
+ stg %r2,(STACK_PTREGS_GPRS+14*8)(%r15)
+ftrace_graph_caller_end:
+ .globl ftrace_graph_caller_end
+#endif
+ lg %r1,(STACK_PTREGS_PSW+8)(%r15)
+ lmg %r2,%r15,(STACK_PTREGS_GPRS+2*8)(%r15)
+ br %r1
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+
+ENTRY(return_to_handler)
+ stmg %r2,%r5,32(%r15)
+ lgr %r1,%r15
+ aghi %r15,-STACK_FRAME_OVERHEAD
+ stg %r1,__SF_BACKCHAIN(%r15)
+ brasl %r14,ftrace_return_to_handler
+ aghi %r15,STACK_FRAME_OVERHEAD
+ lgr %r14,%r2
+ lmg %r2,%r5,32(%r15)
+ br %r14
+
+#endif