ARM: ftrace: function graph tracer support

[mirror_ubuntu-bionic-kernel.git] / arch / arm / kernel / entry-common.S

diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
index fe1d5862b19fcf639a668f5b4b3ab546e86338f9..9f176621166875252e00e3a741a429c24f104ca8 100644 (file)
--- a/arch/arm/kernel/entry-common.S
+++ b/arch/arm/kernel/entry-common.S
@@ -148,6 +148,20 @@ ENDPROC(ret_from_fork)
        adr     r0, .Lftrace_stub
        cmp     r0, r2
        bne     1f
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+       ldr     r1, =ftrace_graph_return
+       ldr     r2, [r1]
+       cmp     r0, r2
+       bne     ftrace_graph_caller\suffix
+
+       ldr     r1, =ftrace_graph_entry
+       ldr     r2, [r1]
+       ldr     r0, =ftrace_graph_entry_stub
+       cmp     r0, r2
+       bne     ftrace_graph_caller\suffix
+#endif
+
        mcount_exit
 
 1:     mcount_get_lr   r1                      @ lr of instrumented func
@@ -172,6 +186,15 @@ ftrace_call\suffix:
        mcount_exit
 .endm
 
+.macro __ftrace_graph_caller
+       sub     r0, fp, #4              @ &lr of instrumented routine (&parent)
+       mov     r1, lr                  @ instrumented routine (func)
+       sub     r1, r1, #MCOUNT_INSN_SIZE
+       mov     r2, fp                  @ frame pointer
+       bl      prepare_ftrace_return
+       mcount_exit
+.endm
+
 #ifdef CONFIG_OLD_MCOUNT
 /*
  * mcount
@@ -206,6 +229,12 @@ ENTRY(ftrace_caller_old)
 ENDPROC(ftrace_caller_old)
 #endif
 
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ENTRY(ftrace_graph_caller_old)
+       __ftrace_graph_caller
+ENDPROC(ftrace_graph_caller_old)
+#endif
+
 .purgem mcount_enter
 .purgem mcount_get_lr
 .purgem mcount_exit
@@ -244,10 +273,27 @@ ENTRY(ftrace_caller)
 ENDPROC(ftrace_caller)
 #endif
 
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ENTRY(ftrace_graph_caller)
+       __ftrace_graph_caller
+ENDPROC(ftrace_graph_caller)
+#endif
+
 .purgem mcount_enter
 .purgem mcount_get_lr
 .purgem mcount_exit
 
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+       .globl return_to_handler
+return_to_handler:
+       stmdb   sp!, {r0-r3}
+       mov     r0, fp                  @ frame pointer
+       bl      ftrace_return_to_handler
+       mov     lr, r0                  @ r0 has real ret addr
+       ldmia   sp!, {r0-r3}
+       mov     pc, lr
+#endif
+
 ENTRY(ftrace_stub)
 .Lftrace_stub:
        mov     pc, lr