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/*
* 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>
.section .kprobes.text, "ax"
ENTRY(ftrace_stub)
br %r14
ENTRY(_mcount)
br %r14
ENTRY(ftrace_caller)
stm %r2,%r5,16(%r15)
bras %r1,1f
0: .long ftrace_trace_function
1: st %r14,56(%r15)
lr %r0,%r15
ahi %r15,-96
l %r3,100(%r15)
la %r2,0(%r14)
st %r0,__SF_BACKCHAIN(%r15)
la %r3,0(%r3)
ahi %r2,-MCOUNT_INSN_SIZE
l %r14,0b-0b(%r1)
l %r14,0(%r14)
basr %r14,%r14
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
l %r2,100(%r15)
l %r3,152(%r15)
ENTRY(ftrace_graph_caller)
# The bras instruction gets runtime patched to call prepare_ftrace_return.
# See ftrace_enable_ftrace_graph_caller. The patched instruction is:
# bras %r14,prepare_ftrace_return
bras %r14,0f
0: st %r2,100(%r15)
#endif
ahi %r15,96
l %r14,56(%r15)
lm %r2,%r5,16(%r15)
br %r14
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
ENTRY(return_to_handler)
stm %r2,%r5,16(%r15)
st %r14,56(%r15)
lr %r0,%r15
ahi %r15,-96
st %r0,__SF_BACKCHAIN(%r15)
bras %r1,0f
.long ftrace_return_to_handler
0: l %r2,0b-0b(%r1)
basr %r14,%r2
lr %r14,%r2
ahi %r15,96
lm %r2,%r5,16(%r15)
br %r14
#endif
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