diff options
Diffstat (limited to 'arch/s390/kernel/mcount64.S')
| -rw-r--r-- | arch/s390/kernel/mcount64.S | 27 |
1 files changed, 7 insertions, 20 deletions
diff --git a/arch/s390/kernel/mcount64.S b/arch/s390/kernel/mcount64.S index b2bae06ad6c7..e73667286ac0 100644 --- a/arch/s390/kernel/mcount64.S +++ b/arch/s390/kernel/mcount64.S @@ -18,12 +18,6 @@ _mcount: #ifdef CONFIG_DYNAMIC_FTRACE br %r14 - .data - .globl ftrace_dyn_func -ftrace_dyn_func: - .quad ftrace_stub - .previous - .globl ftrace_caller ftrace_caller: #endif @@ -37,26 +31,19 @@ ftrace_caller: stg %r1,__SF_BACKCHAIN(%r15) lgr %r2,%r14 lg %r3,168(%r15) -#ifdef CONFIG_DYNAMIC_FTRACE - larl %r14,ftrace_dyn_func -#else larl %r14,ftrace_trace_function -#endif lg %r14,0(%r14) basr %r14,%r14 #ifdef CONFIG_FUNCTION_GRAPH_TRACER -#ifdef CONFIG_DYNAMIC_FTRACE + lg %r2,168(%r15) + lg %r3,272(%r15) .globl ftrace_graph_caller ftrace_graph_caller: - # This unconditional branch gets runtime patched. Change only if - # you know what you are doing. See ftrace_enable_graph_caller(). - j 0f -#endif - lg %r2,272(%r15) - lg %r3,168(%r15) - brasl %r14,prepare_ftrace_return - stg %r2,168(%r15) -0: +# 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) |