| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960 |
- /*
- * 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, _mcount
- 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
- sethi %hi(panicstring), %g3
- sethi %hi(ovstack), %g7 ! cant move to panic stack fast enough
- or %g7, %lo(ovstack), %g7
- add %g7, OVSTACKSIZE, %g7
- sub %g7, STACK_BIAS, %g7
- mov %g7, %sp
- call prom_printf
- or %g3, %lo(panicstring), %o0
- call prom_halt
- nop
- #endif
- 1: retl
- nop
|
