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-rw-r--r--arch/blackfin/kernel/ftrace-entry.S85
1 files changed, 77 insertions, 8 deletions
diff --git a/arch/blackfin/kernel/ftrace-entry.S b/arch/blackfin/kernel/ftrace-entry.S
index d66446b..7eed00b 100644
--- a/arch/blackfin/kernel/ftrace-entry.S
+++ b/arch/blackfin/kernel/ftrace-entry.S
@@ -10,6 +10,18 @@
.text
+#ifdef CONFIG_DYNAMIC_FTRACE
+
+/* Simple stub so we can boot the kernel until runtime patching has
+ * disabled all calls to this. Then it'll be unused.
+ */
+ENTRY(__mcount)
+# if ANOMALY_05000371
+ nop; nop; nop; nop;
+# endif
+ rts;
+ENDPROC(__mcount)
+
/* GCC will have called us before setting up the function prologue, so we
* can clobber the normal scratch registers, but we need to make sure to
* save/restore the registers used for argument passing (R0-R2) in case
@@ -20,15 +32,65 @@
* function. And since GCC pushed the previous RETS for us, the previous
* function will be waiting there. mmmm pie.
*/
+ENTRY(_ftrace_caller)
+# ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
+ /* optional micro optimization: return if stopped */
+ p1.l = _function_trace_stop;
+ p1.h = _function_trace_stop;
+ r3 = [p1];
+ cc = r3 == 0;
+ if ! cc jump _ftrace_stub (bp);
+# endif
+
+ /* save first/second/third function arg and the return register */
+ [--sp] = r2;
+ [--sp] = r0;
+ [--sp] = r1;
+ [--sp] = rets;
+
+ /* function_trace_call(unsigned long ip, unsigned long parent_ip):
+ * ip: this point was called by ...
+ * parent_ip: ... this function
+ * the ip itself will need adjusting for the mcount call
+ */
+ r0 = rets;
+ r1 = [sp + 16]; /* skip the 4 local regs on stack */
+ r0 += -MCOUNT_INSN_SIZE;
+
+.globl _ftrace_call
+_ftrace_call:
+ call _ftrace_stub
+
+# ifdef CONFIG_FUNCTION_GRAPH_TRACER
+.globl _ftrace_graph_call
+_ftrace_graph_call:
+ nop; /* jump _ftrace_graph_caller; */
+# endif
+
+ /* restore state and get out of dodge */
+.Lfinish_trace:
+ rets = [sp++];
+ r1 = [sp++];
+ r0 = [sp++];
+ r2 = [sp++];
+
+.globl _ftrace_stub
+_ftrace_stub:
+ rts;
+ENDPROC(_ftrace_caller)
+
+#else
+
+/* See documentation for _ftrace_caller */
ENTRY(__mcount)
-#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
+# ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
/* optional micro optimization: return if stopped */
p1.l = _function_trace_stop;
p1.h = _function_trace_stop;
r3 = [p1];
cc = r3 == 0;
if ! cc jump _ftrace_stub (bp);
-#endif
+# endif
/* save third function arg early so we can do testing below */
[--sp] = r2;
@@ -44,7 +106,7 @@ ENTRY(__mcount)
cc = r2 == r3;
if ! cc jump .Ldo_trace;
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+# ifdef CONFIG_FUNCTION_GRAPH_TRACER
/* if the ftrace_graph_return function pointer is not set to
* the ftrace_stub entry, call prepare_ftrace_return().
*/
@@ -64,7 +126,7 @@ ENTRY(__mcount)
r3 = [p0];
cc = r2 == r3;
if ! cc jump _ftrace_graph_caller;
-#endif
+# endif
r2 = [sp++];
rts;
@@ -103,6 +165,8 @@ _ftrace_stub:
rts;
ENDPROC(__mcount)
+#endif
+
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
/* The prepare_ftrace_return() function is similar to the trace function
* except it takes a pointer to the location of the frompc. This is so
@@ -110,6 +174,7 @@ ENDPROC(__mcount)
* purposes.
*/
ENTRY(_ftrace_graph_caller)
+# ifndef CONFIG_DYNAMIC_FTRACE
/* save first/second function arg and the return register */
[--sp] = r0;
[--sp] = r1;
@@ -118,9 +183,13 @@ ENTRY(_ftrace_graph_caller)
/* prepare_ftrace_return(parent, self_addr, frame_pointer) */
r0 = sp; /* unsigned long *parent */
r1 = rets; /* unsigned long self_addr */
-#ifdef CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST
+# else
+ r0 = sp; /* unsigned long *parent */
+ r1 = [sp]; /* unsigned long self_addr */
+# endif
+# ifdef CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST
r2 = fp; /* unsigned long frame_pointer */
-#endif
+# endif
r0 += 16; /* skip the 4 local regs on stack */
r1 += -MCOUNT_INSN_SIZE;
call _prepare_ftrace_return;
@@ -139,9 +208,9 @@ ENTRY(_return_to_handler)
[--sp] = r1;
/* get original return address */
-#ifdef CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST
+# ifdef CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST
r0 = fp; /* Blackfin is sane, so omit this */
-#endif
+# endif
call _ftrace_return_to_handler;
rets = r0;
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