Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * This file is subject to the terms and conditions of the GNU General Public |
| 3 | * License. See the file "COPYING" in the main directory of this archive |
| 4 | * for more details. |
| 5 | * |
| 6 | * Copyright (C) 1994 - 1999, 2000 by Ralf Baechle and others. |
Ralf Baechle | 40ac5d4 | 2006-02-08 13:38:18 +0000 | [diff] [blame] | 7 | * Copyright (C) 2005, 2006 by Ralf Baechle (ralf@linux-mips.org) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 8 | * Copyright (C) 1999, 2000 Silicon Graphics, Inc. |
| 9 | * Copyright (C) 2004 Thiemo Seufer |
| 10 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | #include <linux/errno.h> |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/sched.h> |
| 14 | #include <linux/kernel.h> |
| 15 | #include <linux/mm.h> |
| 16 | #include <linux/stddef.h> |
| 17 | #include <linux/unistd.h> |
| 18 | #include <linux/ptrace.h> |
| 19 | #include <linux/slab.h> |
| 20 | #include <linux/mman.h> |
| 21 | #include <linux/personality.h> |
| 22 | #include <linux/sys.h> |
| 23 | #include <linux/user.h> |
| 24 | #include <linux/a.out.h> |
| 25 | #include <linux/init.h> |
| 26 | #include <linux/completion.h> |
Atsushi Nemoto | 6307751 | 2006-02-08 01:48:03 +0900 | [diff] [blame] | 27 | #include <linux/kallsyms.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | |
Ralf Baechle | e50c0a8 | 2005-05-31 11:49:19 +0000 | [diff] [blame] | 29 | #include <asm/abi.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | #include <asm/bootinfo.h> |
| 31 | #include <asm/cpu.h> |
Ralf Baechle | e50c0a8 | 2005-05-31 11:49:19 +0000 | [diff] [blame] | 32 | #include <asm/dsp.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | #include <asm/fpu.h> |
| 34 | #include <asm/pgtable.h> |
| 35 | #include <asm/system.h> |
| 36 | #include <asm/mipsregs.h> |
| 37 | #include <asm/processor.h> |
| 38 | #include <asm/uaccess.h> |
| 39 | #include <asm/io.h> |
| 40 | #include <asm/elf.h> |
| 41 | #include <asm/isadep.h> |
| 42 | #include <asm/inst.h> |
Atsushi Nemoto | 1df0f0f | 2006-09-26 23:44:01 +0900 | [diff] [blame] | 43 | #include <asm/stacktrace.h> |
Ralf Baechle | 41c594a | 2006-04-05 09:45:45 +0100 | [diff] [blame] | 44 | #ifdef CONFIG_MIPS_MT_SMTC |
| 45 | #include <asm/mipsmtregs.h> |
| 46 | extern void smtc_idle_loop_hook(void); |
| 47 | #endif /* CONFIG_MIPS_MT_SMTC */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | |
| 49 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | * The idle thread. There's no useful work to be done, so just try to conserve |
| 51 | * power and have a low exit latency (ie sit in a loop waiting for somebody to |
| 52 | * say that they'd like to reschedule) |
| 53 | */ |
| 54 | ATTRIB_NORET void cpu_idle(void) |
| 55 | { |
| 56 | /* endless idle loop with no priority at all */ |
| 57 | while (1) { |
Ralf Baechle | 41c594a | 2006-04-05 09:45:45 +0100 | [diff] [blame] | 58 | while (!need_resched()) { |
| 59 | #ifdef CONFIG_MIPS_MT_SMTC |
| 60 | smtc_idle_loop_hook(); |
| 61 | #endif /* CONFIG_MIPS_MT_SMTC */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | if (cpu_wait) |
| 63 | (*cpu_wait)(); |
Ralf Baechle | 41c594a | 2006-04-05 09:45:45 +0100 | [diff] [blame] | 64 | } |
Nick Piggin | 5bfb5d6 | 2005-11-08 21:39:01 -0800 | [diff] [blame] | 65 | preempt_enable_no_resched(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 66 | schedule(); |
Nick Piggin | 5bfb5d6 | 2005-11-08 21:39:01 -0800 | [diff] [blame] | 67 | preempt_disable(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 68 | } |
| 69 | } |
| 70 | |
Ralf Baechle | e50c0a8 | 2005-05-31 11:49:19 +0000 | [diff] [blame] | 71 | /* |
| 72 | * Native o32 and N64 ABI without DSP ASE |
| 73 | */ |
Ralf Baechle | e50c0a8 | 2005-05-31 11:49:19 +0000 | [diff] [blame] | 74 | struct mips_abi mips_abi = { |
| 75 | .do_signal = do_signal, |
| 76 | #ifdef CONFIG_TRAD_SIGNALS |
| 77 | .setup_frame = setup_frame, |
| 78 | #endif |
| 79 | .setup_rt_frame = setup_rt_frame |
| 80 | }; |
| 81 | |
| 82 | #ifdef CONFIG_MIPS32_O32 |
| 83 | /* |
| 84 | * o32 compatibility on 64-bit kernels, without DSP ASE |
| 85 | */ |
Ralf Baechle | e50c0a8 | 2005-05-31 11:49:19 +0000 | [diff] [blame] | 86 | struct mips_abi mips_abi_32 = { |
| 87 | .do_signal = do_signal32, |
| 88 | .setup_frame = setup_frame_32, |
| 89 | .setup_rt_frame = setup_rt_frame_32 |
| 90 | }; |
| 91 | #endif /* CONFIG_MIPS32_O32 */ |
| 92 | |
| 93 | #ifdef CONFIG_MIPS32_N32 |
| 94 | /* |
| 95 | * N32 on 64-bit kernels, without DSP ASE |
| 96 | */ |
Ralf Baechle | e50c0a8 | 2005-05-31 11:49:19 +0000 | [diff] [blame] | 97 | struct mips_abi mips_abi_n32 = { |
| 98 | .do_signal = do_signal, |
| 99 | .setup_rt_frame = setup_rt_frame_n32 |
| 100 | }; |
| 101 | #endif /* CONFIG_MIPS32_N32 */ |
| 102 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 103 | asmlinkage void ret_from_fork(void); |
| 104 | |
| 105 | void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp) |
| 106 | { |
| 107 | unsigned long status; |
| 108 | |
| 109 | /* New thread loses kernel privileges. */ |
| 110 | status = regs->cp0_status & ~(ST0_CU0|ST0_CU1|KU_MASK); |
Ralf Baechle | 875d43e | 2005-09-03 15:56:16 -0700 | [diff] [blame] | 111 | #ifdef CONFIG_64BIT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | status &= ~ST0_FR; |
| 113 | status |= (current->thread.mflags & MF_32BIT_REGS) ? 0 : ST0_FR; |
| 114 | #endif |
| 115 | status |= KU_USER; |
| 116 | regs->cp0_status = status; |
| 117 | clear_used_math(); |
Atsushi Nemoto | e04582b | 2006-10-09 00:10:01 +0900 | [diff] [blame] | 118 | clear_fpu_owner(); |
Ralf Baechle | e50c0a8 | 2005-05-31 11:49:19 +0000 | [diff] [blame] | 119 | if (cpu_has_dsp) |
| 120 | __init_dsp(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 121 | regs->cp0_epc = pc; |
| 122 | regs->regs[29] = sp; |
| 123 | current_thread_info()->addr_limit = USER_DS; |
| 124 | } |
| 125 | |
| 126 | void exit_thread(void) |
| 127 | { |
| 128 | } |
| 129 | |
| 130 | void flush_thread(void) |
| 131 | { |
| 132 | } |
| 133 | |
| 134 | int copy_thread(int nr, unsigned long clone_flags, unsigned long usp, |
| 135 | unsigned long unused, struct task_struct *p, struct pt_regs *regs) |
| 136 | { |
Al Viro | 75bb07e | 2006-01-12 01:06:08 -0800 | [diff] [blame] | 137 | struct thread_info *ti = task_thread_info(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 138 | struct pt_regs *childregs; |
| 139 | long childksp; |
Ralf Baechle | 3c37026 | 2005-04-13 17:43:59 +0000 | [diff] [blame] | 140 | p->set_child_tid = p->clear_child_tid = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | |
Al Viro | 75bb07e | 2006-01-12 01:06:08 -0800 | [diff] [blame] | 142 | childksp = (unsigned long)task_stack_page(p) + THREAD_SIZE - 32; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 143 | |
| 144 | preempt_disable(); |
| 145 | |
Ralf Baechle | e50c0a8 | 2005-05-31 11:49:19 +0000 | [diff] [blame] | 146 | if (is_fpu_owner()) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 147 | save_fp(p); |
Ralf Baechle | e50c0a8 | 2005-05-31 11:49:19 +0000 | [diff] [blame] | 148 | |
| 149 | if (cpu_has_dsp) |
| 150 | save_dsp(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 151 | |
| 152 | preempt_enable(); |
| 153 | |
| 154 | /* set up new TSS. */ |
| 155 | childregs = (struct pt_regs *) childksp - 1; |
| 156 | *childregs = *regs; |
| 157 | childregs->regs[7] = 0; /* Clear error flag */ |
| 158 | |
| 159 | #if defined(CONFIG_BINFMT_IRIX) |
| 160 | if (current->personality != PER_LINUX) { |
| 161 | /* Under IRIX things are a little different. */ |
| 162 | childregs->regs[3] = 1; |
| 163 | regs->regs[3] = 0; |
| 164 | } |
| 165 | #endif |
| 166 | childregs->regs[2] = 0; /* Child gets zero as return value */ |
| 167 | regs->regs[2] = p->pid; |
| 168 | |
| 169 | if (childregs->cp0_status & ST0_CU0) { |
| 170 | childregs->regs[28] = (unsigned long) ti; |
| 171 | childregs->regs[29] = childksp; |
| 172 | ti->addr_limit = KERNEL_DS; |
| 173 | } else { |
| 174 | childregs->regs[29] = usp; |
| 175 | ti->addr_limit = USER_DS; |
| 176 | } |
| 177 | p->thread.reg29 = (unsigned long) childregs; |
| 178 | p->thread.reg31 = (unsigned long) ret_from_fork; |
| 179 | |
| 180 | /* |
| 181 | * New tasks lose permission to use the fpu. This accelerates context |
| 182 | * switching for most programs since they don't use the fpu. |
| 183 | */ |
| 184 | p->thread.cp0_status = read_c0_status() & ~(ST0_CU2|ST0_CU1); |
| 185 | childregs->cp0_status &= ~(ST0_CU2|ST0_CU1); |
| 186 | clear_tsk_thread_flag(p, TIF_USEDFPU); |
| 187 | |
Ralf Baechle | f088fc8 | 2006-04-05 09:45:47 +0100 | [diff] [blame] | 188 | #ifdef CONFIG_MIPS_MT_FPAFF |
| 189 | /* |
| 190 | * FPU affinity support is cleaner if we track the |
| 191 | * user-visible CPU affinity from the very beginning. |
| 192 | * The generic cpus_allowed mask will already have |
| 193 | * been copied from the parent before copy_thread |
| 194 | * is invoked. |
| 195 | */ |
| 196 | p->thread.user_cpus_allowed = p->cpus_allowed; |
| 197 | #endif /* CONFIG_MIPS_MT_FPAFF */ |
| 198 | |
Ralf Baechle | 3c37026 | 2005-04-13 17:43:59 +0000 | [diff] [blame] | 199 | if (clone_flags & CLONE_SETTLS) |
| 200 | ti->tp_value = regs->regs[7]; |
| 201 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 202 | return 0; |
| 203 | } |
| 204 | |
| 205 | /* Fill in the fpu structure for a core dump.. */ |
| 206 | int dump_fpu(struct pt_regs *regs, elf_fpregset_t *r) |
| 207 | { |
| 208 | memcpy(r, ¤t->thread.fpu, sizeof(current->thread.fpu)); |
| 209 | |
| 210 | return 1; |
| 211 | } |
| 212 | |
Al Viro | d56efda | 2005-12-16 22:40:47 +0000 | [diff] [blame] | 213 | void elf_dump_regs(elf_greg_t *gp, struct pt_regs *regs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 214 | { |
| 215 | int i; |
| 216 | |
| 217 | for (i = 0; i < EF_R0; i++) |
| 218 | gp[i] = 0; |
| 219 | gp[EF_R0] = 0; |
| 220 | for (i = 1; i <= 31; i++) |
| 221 | gp[EF_R0 + i] = regs->regs[i]; |
| 222 | gp[EF_R26] = 0; |
| 223 | gp[EF_R27] = 0; |
| 224 | gp[EF_LO] = regs->lo; |
| 225 | gp[EF_HI] = regs->hi; |
| 226 | gp[EF_CP0_EPC] = regs->cp0_epc; |
| 227 | gp[EF_CP0_BADVADDR] = regs->cp0_badvaddr; |
| 228 | gp[EF_CP0_STATUS] = regs->cp0_status; |
| 229 | gp[EF_CP0_CAUSE] = regs->cp0_cause; |
| 230 | #ifdef EF_UNUSED0 |
| 231 | gp[EF_UNUSED0] = 0; |
| 232 | #endif |
| 233 | } |
| 234 | |
Ralf Baechle | 71e0e55 | 2005-03-14 10:16:59 +0000 | [diff] [blame] | 235 | int dump_task_regs (struct task_struct *tsk, elf_gregset_t *regs) |
| 236 | { |
Al Viro | 40bc9c6 | 2006-01-12 01:06:07 -0800 | [diff] [blame] | 237 | elf_dump_regs(*regs, task_pt_regs(tsk)); |
Ralf Baechle | 71e0e55 | 2005-03-14 10:16:59 +0000 | [diff] [blame] | 238 | return 1; |
| 239 | } |
| 240 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 241 | int dump_task_fpu (struct task_struct *t, elf_fpregset_t *fpr) |
| 242 | { |
| 243 | memcpy(fpr, &t->thread.fpu, sizeof(current->thread.fpu)); |
| 244 | |
| 245 | return 1; |
| 246 | } |
| 247 | |
| 248 | /* |
| 249 | * Create a kernel thread |
| 250 | */ |
| 251 | ATTRIB_NORET void kernel_thread_helper(void *arg, int (*fn)(void *)) |
| 252 | { |
| 253 | do_exit(fn(arg)); |
| 254 | } |
| 255 | |
| 256 | long kernel_thread(int (*fn)(void *), void *arg, unsigned long flags) |
| 257 | { |
| 258 | struct pt_regs regs; |
| 259 | |
| 260 | memset(®s, 0, sizeof(regs)); |
| 261 | |
| 262 | regs.regs[4] = (unsigned long) arg; |
| 263 | regs.regs[5] = (unsigned long) fn; |
| 264 | regs.cp0_epc = (unsigned long) kernel_thread_helper; |
| 265 | regs.cp0_status = read_c0_status(); |
| 266 | #if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) |
| 267 | regs.cp0_status &= ~(ST0_KUP | ST0_IEC); |
| 268 | regs.cp0_status |= ST0_IEP; |
| 269 | #else |
| 270 | regs.cp0_status |= ST0_EXL; |
| 271 | #endif |
| 272 | |
| 273 | /* Ok, create the new process.. */ |
| 274 | return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, ®s, 0, NULL, NULL); |
| 275 | } |
| 276 | |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 277 | /* |
| 278 | * |
| 279 | */ |
| 280 | struct mips_frame_info { |
| 281 | void *func; |
| 282 | unsigned long func_size; |
| 283 | int frame_size; |
| 284 | int pc_offset; |
| 285 | }; |
Thiemo Seufer | dc953df | 2005-02-21 10:55:16 +0000 | [diff] [blame] | 286 | |
Franck Bui-Huu | c0efbb6 | 2006-08-03 09:29:15 +0200 | [diff] [blame] | 287 | static inline int is_ra_save_ins(union mips_instruction *ip) |
| 288 | { |
| 289 | /* sw / sd $ra, offset($sp) */ |
| 290 | return (ip->i_format.opcode == sw_op || ip->i_format.opcode == sd_op) && |
| 291 | ip->i_format.rs == 29 && |
| 292 | ip->i_format.rt == 31; |
| 293 | } |
| 294 | |
| 295 | static inline int is_jal_jalr_jr_ins(union mips_instruction *ip) |
| 296 | { |
| 297 | if (ip->j_format.opcode == jal_op) |
| 298 | return 1; |
| 299 | if (ip->r_format.opcode != spec_op) |
| 300 | return 0; |
| 301 | return ip->r_format.func == jalr_op || ip->r_format.func == jr_op; |
| 302 | } |
| 303 | |
| 304 | static inline int is_sp_move_ins(union mips_instruction *ip) |
| 305 | { |
| 306 | /* addiu/daddiu sp,sp,-imm */ |
| 307 | if (ip->i_format.rs != 29 || ip->i_format.rt != 29) |
| 308 | return 0; |
| 309 | if (ip->i_format.opcode == addiu_op || ip->i_format.opcode == daddiu_op) |
| 310 | return 1; |
| 311 | return 0; |
| 312 | } |
| 313 | |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 314 | static int get_frame_info(struct mips_frame_info *info) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 315 | { |
Franck Bui-Huu | c0efbb6 | 2006-08-03 09:29:15 +0200 | [diff] [blame] | 316 | union mips_instruction *ip = info->func; |
Franck Bui-Huu | 29b376f | 2006-08-18 16:18:08 +0200 | [diff] [blame] | 317 | unsigned max_insns = info->func_size / sizeof(union mips_instruction); |
| 318 | unsigned i; |
Franck Bui-Huu | c0efbb6 | 2006-08-03 09:29:15 +0200 | [diff] [blame] | 319 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 320 | info->pc_offset = -1; |
Atsushi Nemoto | 6307751 | 2006-02-08 01:48:03 +0900 | [diff] [blame] | 321 | info->frame_size = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 322 | |
Franck Bui-Huu | 29b376f | 2006-08-18 16:18:08 +0200 | [diff] [blame] | 323 | if (!ip) |
| 324 | goto err; |
| 325 | |
| 326 | if (max_insns == 0) |
| 327 | max_insns = 128U; /* unknown function size */ |
| 328 | max_insns = min(128U, max_insns); |
| 329 | |
Franck Bui-Huu | c0efbb6 | 2006-08-03 09:29:15 +0200 | [diff] [blame] | 330 | for (i = 0; i < max_insns; i++, ip++) { |
| 331 | |
| 332 | if (is_jal_jalr_jr_ins(ip)) |
Atsushi Nemoto | 6307751 | 2006-02-08 01:48:03 +0900 | [diff] [blame] | 333 | break; |
Franck Bui-Huu | 0cceb4a | 2006-08-03 09:29:20 +0200 | [diff] [blame] | 334 | if (!info->frame_size) { |
| 335 | if (is_sp_move_ins(ip)) |
| 336 | info->frame_size = - ip->i_format.simmediate; |
| 337 | continue; |
Atsushi Nemoto | 6307751 | 2006-02-08 01:48:03 +0900 | [diff] [blame] | 338 | } |
Franck Bui-Huu | 0cceb4a | 2006-08-03 09:29:20 +0200 | [diff] [blame] | 339 | if (info->pc_offset == -1 && is_ra_save_ins(ip)) { |
Atsushi Nemoto | 6307751 | 2006-02-08 01:48:03 +0900 | [diff] [blame] | 340 | info->pc_offset = |
| 341 | ip->i_format.simmediate / sizeof(long); |
Franck Bui-Huu | 0cceb4a | 2006-08-03 09:29:20 +0200 | [diff] [blame] | 342 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 343 | } |
| 344 | } |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 345 | if (info->frame_size && info->pc_offset >= 0) /* nested */ |
| 346 | return 0; |
| 347 | if (info->pc_offset < 0) /* leaf */ |
| 348 | return 1; |
| 349 | /* prologue seems boggus... */ |
Franck Bui-Huu | 29b376f | 2006-08-18 16:18:08 +0200 | [diff] [blame] | 350 | err: |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 351 | return -1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 352 | } |
| 353 | |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 354 | static struct mips_frame_info schedule_mfi __read_mostly; |
| 355 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 356 | static int __init frame_info_init(void) |
| 357 | { |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 358 | unsigned long size = 0; |
Atsushi Nemoto | 6307751 | 2006-02-08 01:48:03 +0900 | [diff] [blame] | 359 | #ifdef CONFIG_KALLSYMS |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 360 | unsigned long ofs; |
Atsushi Nemoto | 6307751 | 2006-02-08 01:48:03 +0900 | [diff] [blame] | 361 | |
Franck Bui-Huu | 55b7428 | 2006-10-13 13:37:35 +0200 | [diff] [blame] | 362 | kallsyms_lookup_size_offset((unsigned long)schedule, &size, &ofs); |
Atsushi Nemoto | 6307751 | 2006-02-08 01:48:03 +0900 | [diff] [blame] | 363 | #endif |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 364 | schedule_mfi.func = schedule; |
| 365 | schedule_mfi.func_size = size; |
| 366 | |
| 367 | get_frame_info(&schedule_mfi); |
Franck Bui-Huu | 6057a79 | 2006-08-03 09:29:18 +0200 | [diff] [blame] | 368 | |
| 369 | /* |
| 370 | * Without schedule() frame info, result given by |
| 371 | * thread_saved_pc() and get_wchan() are not reliable. |
| 372 | */ |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 373 | if (schedule_mfi.pc_offset < 0) |
Franck Bui-Huu | 6057a79 | 2006-08-03 09:29:18 +0200 | [diff] [blame] | 374 | printk("Can't analyze schedule() prologue at %p\n", schedule); |
Atsushi Nemoto | 6307751 | 2006-02-08 01:48:03 +0900 | [diff] [blame] | 375 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 376 | return 0; |
| 377 | } |
| 378 | |
| 379 | arch_initcall(frame_info_init); |
| 380 | |
| 381 | /* |
| 382 | * Return saved PC of a blocked thread. |
| 383 | */ |
| 384 | unsigned long thread_saved_pc(struct task_struct *tsk) |
| 385 | { |
| 386 | struct thread_struct *t = &tsk->thread; |
| 387 | |
| 388 | /* New born processes are a special case */ |
| 389 | if (t->reg31 == (unsigned long) ret_from_fork) |
| 390 | return t->reg31; |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 391 | if (schedule_mfi.pc_offset < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 392 | return 0; |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 393 | return ((unsigned long *)t->reg29)[schedule_mfi.pc_offset]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | } |
| 395 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 396 | |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 397 | #ifdef CONFIG_KALLSYMS |
Franck Bui-Huu | 4d157d5 | 2006-08-03 09:29:21 +0200 | [diff] [blame] | 398 | /* used by show_backtrace() */ |
| 399 | unsigned long unwind_stack(struct task_struct *task, unsigned long *sp, |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 400 | unsigned long pc, unsigned long *ra) |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 401 | { |
| 402 | unsigned long stack_page; |
| 403 | struct mips_frame_info info; |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 404 | unsigned long size, ofs; |
Franck Bui-Huu | 4d157d5 | 2006-08-03 09:29:21 +0200 | [diff] [blame] | 405 | int leaf; |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 406 | extern void ret_from_irq(void); |
| 407 | extern void ret_from_exception(void); |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 408 | |
| 409 | stack_page = (unsigned long)task_stack_page(task); |
| 410 | if (!stack_page) |
| 411 | return 0; |
| 412 | |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 413 | /* |
| 414 | * If we reached the bottom of interrupt context, |
| 415 | * return saved pc in pt_regs. |
| 416 | */ |
| 417 | if (pc == (unsigned long)ret_from_irq || |
| 418 | pc == (unsigned long)ret_from_exception) { |
| 419 | struct pt_regs *regs; |
| 420 | if (*sp >= stack_page && |
| 421 | *sp + sizeof(*regs) <= stack_page + THREAD_SIZE - 32) { |
| 422 | regs = (struct pt_regs *)*sp; |
| 423 | pc = regs->cp0_epc; |
| 424 | if (__kernel_text_address(pc)) { |
| 425 | *sp = regs->regs[29]; |
| 426 | *ra = regs->regs[31]; |
| 427 | return pc; |
| 428 | } |
| 429 | } |
| 430 | return 0; |
| 431 | } |
Franck Bui-Huu | 55b7428 | 2006-10-13 13:37:35 +0200 | [diff] [blame] | 432 | if (!kallsyms_lookup_size_offset(pc, &size, &ofs)) |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 433 | return 0; |
Franck Bui-Huu | 1fd6909 | 2006-08-18 16:18:07 +0200 | [diff] [blame] | 434 | /* |
| 435 | * Return ra if an exception occured at the first instruction |
| 436 | */ |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 437 | if (unlikely(ofs == 0)) { |
| 438 | pc = *ra; |
| 439 | *ra = 0; |
| 440 | return pc; |
| 441 | } |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 442 | |
| 443 | info.func = (void *)(pc - ofs); |
| 444 | info.func_size = ofs; /* analyze from start to ofs */ |
Franck Bui-Huu | 4d157d5 | 2006-08-03 09:29:21 +0200 | [diff] [blame] | 445 | leaf = get_frame_info(&info); |
| 446 | if (leaf < 0) |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 447 | return 0; |
| 448 | |
Franck Bui-Huu | 4d157d5 | 2006-08-03 09:29:21 +0200 | [diff] [blame] | 449 | if (*sp < stack_page || |
| 450 | *sp + info.frame_size > stack_page + THREAD_SIZE - 32) |
| 451 | return 0; |
| 452 | |
| 453 | if (leaf) |
| 454 | /* |
| 455 | * For some extreme cases, get_frame_info() can |
| 456 | * consider wrongly a nested function as a leaf |
| 457 | * one. In that cases avoid to return always the |
| 458 | * same value. |
| 459 | */ |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 460 | pc = pc != *ra ? *ra : 0; |
Franck Bui-Huu | 4d157d5 | 2006-08-03 09:29:21 +0200 | [diff] [blame] | 461 | else |
| 462 | pc = ((unsigned long *)(*sp))[info.pc_offset]; |
| 463 | |
| 464 | *sp += info.frame_size; |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 465 | *ra = 0; |
Franck Bui-Huu | 4d157d5 | 2006-08-03 09:29:21 +0200 | [diff] [blame] | 466 | return __kernel_text_address(pc) ? pc : 0; |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 467 | } |
| 468 | #endif |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 469 | |
| 470 | /* |
| 471 | * get_wchan - a maintenance nightmare^W^Wpain in the ass ... |
| 472 | */ |
| 473 | unsigned long get_wchan(struct task_struct *task) |
| 474 | { |
| 475 | unsigned long pc = 0; |
| 476 | #ifdef CONFIG_KALLSYMS |
| 477 | unsigned long sp; |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 478 | unsigned long ra = 0; |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 479 | #endif |
| 480 | |
| 481 | if (!task || task == current || task->state == TASK_RUNNING) |
| 482 | goto out; |
| 483 | if (!task_stack_page(task)) |
| 484 | goto out; |
| 485 | |
| 486 | pc = thread_saved_pc(task); |
| 487 | |
| 488 | #ifdef CONFIG_KALLSYMS |
| 489 | sp = task->thread.reg29 + schedule_mfi.frame_size; |
| 490 | |
| 491 | while (in_sched_functions(pc)) |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 492 | pc = unwind_stack(task, &sp, pc, &ra); |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 493 | #endif |
| 494 | |
| 495 | out: |
| 496 | return pc; |
| 497 | } |