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/*
* Copyright (C) 2000 Anton Blanchard (anton@linuxcare.com)
*
* This file implements mcount(), which is used to collect profiling data.
* This can also be tweaked for kernel stack overflow detection.
*/
#include <linux/linkage.h>
/*
* This is the main variant and is called by C code. GCC's -pg option
* automatically instruments every C function with a call to this.
*/
.text
.align 32
.globl _mcount
.type _mcount,#function
.globl mcount
.type mcount,#function
_mcount:
mcount:
#ifdef CONFIG_FUNCTION_TRACER
#ifdef CONFIG_DYNAMIC_FTRACE
/* Do nothing, the retl/nop below is all we need. */
#else
sethi %hi(function_trace_stop), %g1
lduw [%g1 + %lo(function_trace_stop)], %g2
brnz,pn %g2, 1f
sethi %hi(ftrace_trace_function), %g1
sethi %hi(ftrace_stub), %g2
ldx [%g1 + %lo(ftrace_trace_function)], %g1
or %g2, %lo(ftrace_stub), %g2
cmp %g1, %g2
be,pn %icc, 1f
mov %i7, %o1
jmpl %g1, %g0
mov %o7, %o0
/* not reached */
1:
#endif
#endif
retl
nop
.size _mcount,.-_mcount
.size mcount,.-mcount
#ifdef CONFIG_FUNCTION_TRACER
.globl ftrace_stub
.type ftrace_stub,#function
ftrace_stub:
retl
nop
.size ftrace_stub,.-ftrace_stub
#ifdef CONFIG_DYNAMIC_FTRACE
.globl ftrace_caller
.type ftrace_caller,#function
ftrace_caller:
sethi %hi(function_trace_stop), %g1
mov %i7, %o1
lduw [%g1 + %lo(function_trace_stop)], %g2
brnz,pn %g2, ftrace_stub
mov %o7, %o0
.globl ftrace_call
ftrace_call:
/* If the final kernel link ever turns on relaxation, we'll need
* to do something about this tail call. Otherwise the linker
* will rewrite the call into a branch and nop out the move
* instruction.
*/
call ftrace_stub
mov %o0, %o7
retl
nop
.size ftrace_call,.-ftrace_call
.size ftrace_caller,.-ftrace_caller
#endif
#endif
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