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-rw-r--r--arch/sparc/lib/mcount.S143
1 files changed, 143 insertions, 0 deletions
diff --git a/arch/sparc/lib/mcount.S b/arch/sparc/lib/mcount.S
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+/*
+ * 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