sh: Function graph tracer support

[firefly-linux-kernel-4.4.55.git] / arch / sh / lib / mcount.S

diff --git a/arch/sh/lib/mcount.S b/arch/sh/lib/mcount.S
index 8596483f7b4128b3ff0c25e372f45670d63fc910..bd3ec648beccb79f256ef66af693395de4506dc4 100644 (file)
--- a/arch/sh/lib/mcount.S
+++ b/arch/sh/lib/mcount.S
@@ -111,14 +111,62 @@ mcount_call:
        jsr     @r6
         nop
 
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+       mov.l   .Lftrace_graph_return, r6
+       mov.l   .Lftrace_stub, r7
+       cmp/eq  r6, r7
+       bt      1f
+
+       mov.l   .Lftrace_graph_caller, r0
+       jmp     @r0
+        nop
+
+1:
+       mov.l   .Lftrace_graph_entry, r6
+       mov.l   .Lftrace_graph_entry_stub, r7
+       cmp/eq  r6, r7
+       bt      skip_trace
+
+       mov.l   .Lftrace_graph_caller, r0
+       jmp     @r0
+        nop
+
+       .align 2
+.Lftrace_graph_return:
+       .long   ftrace_graph_return
+.Lftrace_graph_entry:
+       .long   ftrace_graph_entry
+.Lftrace_graph_entry_stub:
+       .long   ftrace_graph_entry_stub
+.Lftrace_graph_caller:
+       .long   ftrace_graph_caller
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+
+       .globl skip_trace
 skip_trace:
        MCOUNT_LEAVE()
 
        .align 2
 .Lftrace_trace_function:
-       .long   ftrace_trace_function
+       .long   ftrace_trace_function
 
 #ifdef CONFIG_DYNAMIC_FTRACE
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+/*
+ * NOTE: Do not move either ftrace_graph_call or ftrace_caller
+ * as this will affect the calculation of GRAPH_INSN_OFFSET.
+ */
+       .globl ftrace_graph_call
+ftrace_graph_call:
+       mov.l   .Lskip_trace, r0
+       jmp     @r0
+        nop
+
+       .align 2
+.Lskip_trace:
+       .long   skip_trace
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+
        .globl ftrace_caller
 ftrace_caller:
        mov.l   .Lfunction_trace_stop, r0
@@ -136,7 +184,12 @@ ftrace_call:
        jsr     @r6
         nop
 
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+       bra     ftrace_graph_call
+        nop
+#else
        MCOUNT_LEAVE()
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 #endif /* CONFIG_DYNAMIC_FTRACE */
 
 /*
@@ -188,3 +241,65 @@ stack_panic:
 .Lpanic_str:
        .string "Stack error"
 #endif /* CONFIG_STACK_DEBUG */
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+       .globl  ftrace_graph_caller
+ftrace_graph_caller:
+       mov.l   2f, r0
+       mov.l   @r0, r0
+       tst     r0, r0
+       bt      1f
+
+       mov.l   3f, r1
+       jmp     @r1
+        nop
+1:
+       /*
+        * MCOUNT_ENTER() pushed 5 registers onto the stack, so
+        * the stack address containing our return address is
+        * r15 + 20.
+        */
+       mov     #20, r0
+       add     r15, r0
+       mov     r0, r4
+
+       mov.l   .Lprepare_ftrace_return, r0
+       jsr     @r0
+        nop
+
+       MCOUNT_LEAVE()
+
+       .align 2
+2:     .long   function_trace_stop
+3:     .long   skip_trace
+.Lprepare_ftrace_return:
+       .long   prepare_ftrace_return
+
+       .globl  return_to_handler
+return_to_handler:
+       /*
+        * Save the return values.
+        */
+       mov.l   r0, @-r15
+       mov.l   r1, @-r15
+
+       mov     #0, r4
+
+       mov.l   .Lftrace_return_to_handler, r0
+       jsr     @r0
+        nop
+
+       /*
+        * The return value from ftrace_return_handler has the real
+        * address that we should return to.
+        */
+       lds     r0, pr
+       mov.l   @r15+, r1
+       rts
+        mov.l  @r15+, r0
+
+
+       .align 2
+.Lftrace_return_to_handler:
+       .long   ftrace_return_to_handler
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */