1 files changed, 143 insertions, 0 deletions

diff --git a/arch/sparc/lib/mcount.S b/arch/sparc/lib/mcount.S
new file mode 100644
index 000000000000..7ce9c65f3592
--- /dev/null
+++ b/arch/sparc/lib/mcount.S
@@ -0,0 +1,143 @@
+/*
+ * Copyright (C) 2000 Anton Blanchard (anton@linuxcare.com)
+ *
+ * This file implements mcount(), which is used to collect profiling data.
+ * This can also be tweaked for kernel stack overflow detection.
+ */
+
+#include <linux/linkage.h>
+
+#include <asm/ptrace.h>
+#include <asm/thread_info.h>
+
+/*
+ * This is the main variant and is called by C code.  GCC's -pg option
+ * automatically instruments every C function with a call to this.
+ */
+
+#ifdef CONFIG_STACK_DEBUG
+
+#define OVSTACKSIZE     4096            /* lets hope this is enough */
+
+        .data
+        .align          8
+panicstring:
+        .asciz          "Stack overflow\n"
+        .align          8
+ovstack:
+        .skip           OVSTACKSIZE
+#endif
+        .text
+        .align          32
+        .globl          _mcount
+        .type           _mcount,#function
+        .globl          mcount
+        .type           mcount,#function
+_mcount:
+mcount:
+#ifdef CONFIG_STACK_DEBUG
+        /*
+         * Check whether %sp is dangerously low.
+         */
+        ldub            [%g6 + TI_FPDEPTH], %g1
+        srl             %g1, 1, %g3
+        add             %g3, 1, %g3
+        sllx            %g3, 8, %g3                     ! each fpregs frame is 256b
+        add             %g3, 192, %g3
+        add             %g6, %g3, %g3                   ! where does task_struct+frame end?
+        sub             %g3, STACK_BIAS, %g3
+        cmp             %sp, %g3
+        bg,pt           %xcc, 1f
+         nop
+        lduh            [%g6 + TI_CPU], %g1
+        sethi           %hi(hardirq_stack), %g3
+        or              %g3, %lo(hardirq_stack), %g3
+        sllx            %g1, 3, %g1
+        ldx             [%g3 + %g1], %g7
+        sub             %g7, STACK_BIAS, %g7
+        cmp             %sp, %g7
+        bleu,pt         %xcc, 2f
+         sethi          %hi(THREAD_SIZE), %g3
+        add             %g7, %g3, %g7
+        cmp             %sp, %g7
+        blu,pn          %xcc, 1f
+2:       sethi          %hi(softirq_stack), %g3
+        or              %g3, %lo(softirq_stack), %g3
+        ldx             [%g3 + %g1], %g7
+        cmp             %sp, %g7
+        bleu,pt         %xcc, 2f
+         sethi          %hi(THREAD_SIZE), %g3
+        add             %g7, %g3, %g7
+        cmp             %sp, %g7
+        blu,pn          %xcc, 1f
+         nop
+        /* If we are already on ovstack, don't hop onto it
+         * again, we are already trying to output the stack overflow
+         * message.
+         */
+        sethi           %hi(ovstack), %g7               ! cant move to panic stack fast enough
+         or             %g7, %lo(ovstack), %g7
+        add             %g7, OVSTACKSIZE, %g3
+        sub             %g3, STACK_BIAS + 192, %g3
+        sub             %g7, STACK_BIAS, %g7
+        cmp             %sp, %g7
+        blu,pn          %xcc, 2f
+         cmp            %sp, %g3
+        bleu,pn         %xcc, 1f
+         nop
+2:      mov             %g3, %sp
+        sethi           %hi(panicstring), %g3
+        call            prom_printf
+         or             %g3, %lo(panicstring), %o0
+        call            prom_halt
+         nop
+1:
+#endif
+#ifdef CONFIG_FUNCTION_TRACER
+#ifdef CONFIG_DYNAMIC_FTRACE
+        mov             %o7, %o0
+        .globl          mcount_call
+mcount_call:
+        call            ftrace_stub
+         mov            %o0, %o7
+#else
+        sethi           %hi(ftrace_trace_function), %g1
+        sethi           %hi(ftrace_stub), %g2
+        ldx             [%g1 + %lo(ftrace_trace_function)], %g1
+        or              %g2, %lo(ftrace_stub), %g2
+        cmp             %g1, %g2
+        be,pn           %icc, 1f
+         mov            %i7, %o1
+        jmpl            %g1, %g0
+         mov            %o7, %o0
+        /* not reached */
+1:
+#endif
+#endif
+        retl
+         nop
+        .size           _mcount,.-_mcount
+        .size           mcount,.-mcount
+
+#ifdef CONFIG_FUNCTION_TRACER
+        .globl          ftrace_stub
+        .type           ftrace_stub,#function
+ftrace_stub:
+        retl
+         nop
+        .size           ftrace_stub,.-ftrace_stub
+#ifdef CONFIG_DYNAMIC_FTRACE
+        .globl          ftrace_caller
+        .type           ftrace_caller,#function
+ftrace_caller:
+        mov             %i7, %o1
+        mov             %o7, %o0
+        .globl          ftrace_call
+ftrace_call:
+        call            ftrace_stub
+         mov            %o0, %o7
+        retl
+         nop
+        .size           ftrace_caller,.-ftrace_caller
+#endif
+#endif