[S390] cleanup ftrace backend functions
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/mcount64.S b/arch/s390/kernel/mcount64.S
index b2bae06..e736672 100644
--- a/arch/s390/kernel/mcount64.S
+++ b/arch/s390/kernel/mcount64.S
@@ -18,12 +18,6 @@
#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 @@
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)
