linux/arch/s390/kernel/mcount64.S
Martin Schwidefsky 4cc9bed034 [S390] cleanup ftrace backend functions
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-01-05 12:47:31 +01:00

68 lines
1.2 KiB
ArmAsm

/*
* Copyright IBM Corp. 2008,2009
*
* Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
*
*/
#include <asm/asm-offsets.h>
.section .kprobes.text, "ax"
.globl ftrace_stub
ftrace_stub:
br %r14
.globl _mcount
_mcount:
#ifdef CONFIG_DYNAMIC_FTRACE
br %r14
.globl ftrace_caller
ftrace_caller:
#endif
larl %r1,function_trace_stop
icm %r1,0xf,0(%r1)
bnzr %r14
stmg %r2,%r5,32(%r15)
stg %r14,112(%r15)
lgr %r1,%r15
aghi %r15,-160
stg %r1,__SF_BACKCHAIN(%r15)
lgr %r2,%r14
lg %r3,168(%r15)
larl %r14,ftrace_trace_function
lg %r14,0(%r14)
basr %r14,%r14
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
lg %r2,168(%r15)
lg %r3,272(%r15)
.globl ftrace_graph_caller
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: stg %r2,168(%r15)
#endif
aghi %r15,160
lmg %r2,%r5,32(%r15)
lg %r14,112(%r15)
br %r14
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
.globl return_to_handler
return_to_handler:
stmg %r2,%r5,32(%r15)
lgr %r1,%r15
aghi %r15,-160
stg %r1,__SF_BACKCHAIN(%r15)
brasl %r14,ftrace_return_to_handler
aghi %r15,160
lgr %r14,%r2
lmg %r2,%r5,32(%r15)
br %r14
#endif