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1da177e4 | 1 | /* |
5a4f7c66 | 2 | * arch/sh/kernel/process_64.c |
1da177e4 | 3 | * |
5a4f7c66 | 4 | * This file handles the architecture-dependent parts of process handling.. |
1da177e4 LT |
5 | * |
6 | * Copyright (C) 2000, 2001 Paolo Alberelli | |
5a4f7c66 | 7 | * Copyright (C) 2003 - 2007 Paul Mundt |
1da177e4 LT |
8 | * Copyright (C) 2003, 2004 Richard Curnow |
9 | * | |
10 | * Started from SH3/4 version: | |
11 | * Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima | |
12 | * | |
13 | * In turn started from i386 version: | |
14 | * Copyright (C) 1995 Linus Torvalds | |
15 | * | |
5a4f7c66 PM |
16 | * This file is subject to the terms and conditions of the GNU General Public |
17 | * License. See the file "COPYING" in the main directory of this archive | |
18 | * for more details. | |
1da177e4 | 19 | */ |
1da177e4 | 20 | #include <linux/mm.h> |
78d98277 | 21 | #include <linux/fs.h> |
1da177e4 | 22 | #include <linux/ptrace.h> |
1da177e4 | 23 | #include <linux/reboot.h> |
5a0e3ad6 | 24 | #include <linux/slab.h> |
1da177e4 | 25 | #include <linux/init.h> |
821278a7 | 26 | #include <linux/module.h> |
a7aa92d1 | 27 | #include <linux/io.h> |
fa43972f | 28 | #include <asm/syscalls.h> |
7c0f6ba6 | 29 | #include <linux/uaccess.h> |
1da177e4 | 30 | #include <asm/pgtable.h> |
df0fb256 | 31 | #include <asm/mmu_context.h> |
50387b3e | 32 | #include <asm/fpu.h> |
e839ca52 | 33 | #include <asm/switch_to.h> |
1da177e4 LT |
34 | |
35 | struct task_struct *last_task_used_math = NULL; | |
3a9485da | 36 | struct pt_regs fake_swapper_regs = { 0, }; |
1da177e4 | 37 | |
fbb82b03 | 38 | void show_regs(struct pt_regs *regs) |
1da177e4 LT |
39 | { |
40 | unsigned long long ah, al, bh, bl, ch, cl; | |
41 | ||
42 | printk("\n"); | |
a43cb95d | 43 | show_regs_print_info(KERN_DEFAULT); |
1da177e4 LT |
44 | |
45 | ah = (regs->pc) >> 32; | |
46 | al = (regs->pc) & 0xffffffff; | |
47 | bh = (regs->regs[18]) >> 32; | |
48 | bl = (regs->regs[18]) & 0xffffffff; | |
49 | ch = (regs->regs[15]) >> 32; | |
50 | cl = (regs->regs[15]) & 0xffffffff; | |
51 | printk("PC : %08Lx%08Lx LINK: %08Lx%08Lx SP : %08Lx%08Lx\n", | |
52 | ah, al, bh, bl, ch, cl); | |
53 | ||
54 | ah = (regs->sr) >> 32; | |
55 | al = (regs->sr) & 0xffffffff; | |
56 | asm volatile ("getcon " __TEA ", %0" : "=r" (bh)); | |
57 | asm volatile ("getcon " __TEA ", %0" : "=r" (bl)); | |
58 | bh = (bh) >> 32; | |
59 | bl = (bl) & 0xffffffff; | |
60 | asm volatile ("getcon " __KCR0 ", %0" : "=r" (ch)); | |
61 | asm volatile ("getcon " __KCR0 ", %0" : "=r" (cl)); | |
62 | ch = (ch) >> 32; | |
63 | cl = (cl) & 0xffffffff; | |
64 | printk("SR : %08Lx%08Lx TEA : %08Lx%08Lx KCR0: %08Lx%08Lx\n", | |
65 | ah, al, bh, bl, ch, cl); | |
66 | ||
67 | ah = (regs->regs[0]) >> 32; | |
68 | al = (regs->regs[0]) & 0xffffffff; | |
69 | bh = (regs->regs[1]) >> 32; | |
70 | bl = (regs->regs[1]) & 0xffffffff; | |
71 | ch = (regs->regs[2]) >> 32; | |
72 | cl = (regs->regs[2]) & 0xffffffff; | |
73 | printk("R0 : %08Lx%08Lx R1 : %08Lx%08Lx R2 : %08Lx%08Lx\n", | |
74 | ah, al, bh, bl, ch, cl); | |
75 | ||
76 | ah = (regs->regs[3]) >> 32; | |
77 | al = (regs->regs[3]) & 0xffffffff; | |
78 | bh = (regs->regs[4]) >> 32; | |
79 | bl = (regs->regs[4]) & 0xffffffff; | |
80 | ch = (regs->regs[5]) >> 32; | |
81 | cl = (regs->regs[5]) & 0xffffffff; | |
82 | printk("R3 : %08Lx%08Lx R4 : %08Lx%08Lx R5 : %08Lx%08Lx\n", | |
83 | ah, al, bh, bl, ch, cl); | |
84 | ||
85 | ah = (regs->regs[6]) >> 32; | |
86 | al = (regs->regs[6]) & 0xffffffff; | |
87 | bh = (regs->regs[7]) >> 32; | |
88 | bl = (regs->regs[7]) & 0xffffffff; | |
89 | ch = (regs->regs[8]) >> 32; | |
90 | cl = (regs->regs[8]) & 0xffffffff; | |
91 | printk("R6 : %08Lx%08Lx R7 : %08Lx%08Lx R8 : %08Lx%08Lx\n", | |
92 | ah, al, bh, bl, ch, cl); | |
93 | ||
94 | ah = (regs->regs[9]) >> 32; | |
95 | al = (regs->regs[9]) & 0xffffffff; | |
96 | bh = (regs->regs[10]) >> 32; | |
97 | bl = (regs->regs[10]) & 0xffffffff; | |
98 | ch = (regs->regs[11]) >> 32; | |
99 | cl = (regs->regs[11]) & 0xffffffff; | |
100 | printk("R9 : %08Lx%08Lx R10 : %08Lx%08Lx R11 : %08Lx%08Lx\n", | |
101 | ah, al, bh, bl, ch, cl); | |
102 | ||
103 | ah = (regs->regs[12]) >> 32; | |
104 | al = (regs->regs[12]) & 0xffffffff; | |
105 | bh = (regs->regs[13]) >> 32; | |
106 | bl = (regs->regs[13]) & 0xffffffff; | |
107 | ch = (regs->regs[14]) >> 32; | |
108 | cl = (regs->regs[14]) & 0xffffffff; | |
109 | printk("R12 : %08Lx%08Lx R13 : %08Lx%08Lx R14 : %08Lx%08Lx\n", | |
110 | ah, al, bh, bl, ch, cl); | |
111 | ||
112 | ah = (regs->regs[16]) >> 32; | |
113 | al = (regs->regs[16]) & 0xffffffff; | |
114 | bh = (regs->regs[17]) >> 32; | |
115 | bl = (regs->regs[17]) & 0xffffffff; | |
116 | ch = (regs->regs[19]) >> 32; | |
117 | cl = (regs->regs[19]) & 0xffffffff; | |
118 | printk("R16 : %08Lx%08Lx R17 : %08Lx%08Lx R19 : %08Lx%08Lx\n", | |
119 | ah, al, bh, bl, ch, cl); | |
120 | ||
121 | ah = (regs->regs[20]) >> 32; | |
122 | al = (regs->regs[20]) & 0xffffffff; | |
123 | bh = (regs->regs[21]) >> 32; | |
124 | bl = (regs->regs[21]) & 0xffffffff; | |
125 | ch = (regs->regs[22]) >> 32; | |
126 | cl = (regs->regs[22]) & 0xffffffff; | |
127 | printk("R20 : %08Lx%08Lx R21 : %08Lx%08Lx R22 : %08Lx%08Lx\n", | |
128 | ah, al, bh, bl, ch, cl); | |
129 | ||
130 | ah = (regs->regs[23]) >> 32; | |
131 | al = (regs->regs[23]) & 0xffffffff; | |
132 | bh = (regs->regs[24]) >> 32; | |
133 | bl = (regs->regs[24]) & 0xffffffff; | |
134 | ch = (regs->regs[25]) >> 32; | |
135 | cl = (regs->regs[25]) & 0xffffffff; | |
136 | printk("R23 : %08Lx%08Lx R24 : %08Lx%08Lx R25 : %08Lx%08Lx\n", | |
137 | ah, al, bh, bl, ch, cl); | |
138 | ||
139 | ah = (regs->regs[26]) >> 32; | |
140 | al = (regs->regs[26]) & 0xffffffff; | |
141 | bh = (regs->regs[27]) >> 32; | |
142 | bl = (regs->regs[27]) & 0xffffffff; | |
143 | ch = (regs->regs[28]) >> 32; | |
144 | cl = (regs->regs[28]) & 0xffffffff; | |
145 | printk("R26 : %08Lx%08Lx R27 : %08Lx%08Lx R28 : %08Lx%08Lx\n", | |
146 | ah, al, bh, bl, ch, cl); | |
147 | ||
148 | ah = (regs->regs[29]) >> 32; | |
149 | al = (regs->regs[29]) & 0xffffffff; | |
150 | bh = (regs->regs[30]) >> 32; | |
151 | bl = (regs->regs[30]) & 0xffffffff; | |
152 | ch = (regs->regs[31]) >> 32; | |
153 | cl = (regs->regs[31]) & 0xffffffff; | |
154 | printk("R29 : %08Lx%08Lx R30 : %08Lx%08Lx R31 : %08Lx%08Lx\n", | |
155 | ah, al, bh, bl, ch, cl); | |
156 | ||
157 | ah = (regs->regs[32]) >> 32; | |
158 | al = (regs->regs[32]) & 0xffffffff; | |
159 | bh = (regs->regs[33]) >> 32; | |
160 | bl = (regs->regs[33]) & 0xffffffff; | |
161 | ch = (regs->regs[34]) >> 32; | |
162 | cl = (regs->regs[34]) & 0xffffffff; | |
163 | printk("R32 : %08Lx%08Lx R33 : %08Lx%08Lx R34 : %08Lx%08Lx\n", | |
164 | ah, al, bh, bl, ch, cl); | |
165 | ||
166 | ah = (regs->regs[35]) >> 32; | |
167 | al = (regs->regs[35]) & 0xffffffff; | |
168 | bh = (regs->regs[36]) >> 32; | |
169 | bl = (regs->regs[36]) & 0xffffffff; | |
170 | ch = (regs->regs[37]) >> 32; | |
171 | cl = (regs->regs[37]) & 0xffffffff; | |
172 | printk("R35 : %08Lx%08Lx R36 : %08Lx%08Lx R37 : %08Lx%08Lx\n", | |
173 | ah, al, bh, bl, ch, cl); | |
174 | ||
175 | ah = (regs->regs[38]) >> 32; | |
176 | al = (regs->regs[38]) & 0xffffffff; | |
177 | bh = (regs->regs[39]) >> 32; | |
178 | bl = (regs->regs[39]) & 0xffffffff; | |
179 | ch = (regs->regs[40]) >> 32; | |
180 | cl = (regs->regs[40]) & 0xffffffff; | |
181 | printk("R38 : %08Lx%08Lx R39 : %08Lx%08Lx R40 : %08Lx%08Lx\n", | |
182 | ah, al, bh, bl, ch, cl); | |
183 | ||
184 | ah = (regs->regs[41]) >> 32; | |
185 | al = (regs->regs[41]) & 0xffffffff; | |
186 | bh = (regs->regs[42]) >> 32; | |
187 | bl = (regs->regs[42]) & 0xffffffff; | |
188 | ch = (regs->regs[43]) >> 32; | |
189 | cl = (regs->regs[43]) & 0xffffffff; | |
190 | printk("R41 : %08Lx%08Lx R42 : %08Lx%08Lx R43 : %08Lx%08Lx\n", | |
191 | ah, al, bh, bl, ch, cl); | |
192 | ||
193 | ah = (regs->regs[44]) >> 32; | |
194 | al = (regs->regs[44]) & 0xffffffff; | |
195 | bh = (regs->regs[45]) >> 32; | |
196 | bl = (regs->regs[45]) & 0xffffffff; | |
197 | ch = (regs->regs[46]) >> 32; | |
198 | cl = (regs->regs[46]) & 0xffffffff; | |
199 | printk("R44 : %08Lx%08Lx R45 : %08Lx%08Lx R46 : %08Lx%08Lx\n", | |
200 | ah, al, bh, bl, ch, cl); | |
201 | ||
202 | ah = (regs->regs[47]) >> 32; | |
203 | al = (regs->regs[47]) & 0xffffffff; | |
204 | bh = (regs->regs[48]) >> 32; | |
205 | bl = (regs->regs[48]) & 0xffffffff; | |
206 | ch = (regs->regs[49]) >> 32; | |
207 | cl = (regs->regs[49]) & 0xffffffff; | |
208 | printk("R47 : %08Lx%08Lx R48 : %08Lx%08Lx R49 : %08Lx%08Lx\n", | |
209 | ah, al, bh, bl, ch, cl); | |
210 | ||
211 | ah = (regs->regs[50]) >> 32; | |
212 | al = (regs->regs[50]) & 0xffffffff; | |
213 | bh = (regs->regs[51]) >> 32; | |
214 | bl = (regs->regs[51]) & 0xffffffff; | |
215 | ch = (regs->regs[52]) >> 32; | |
216 | cl = (regs->regs[52]) & 0xffffffff; | |
217 | printk("R50 : %08Lx%08Lx R51 : %08Lx%08Lx R52 : %08Lx%08Lx\n", | |
218 | ah, al, bh, bl, ch, cl); | |
219 | ||
220 | ah = (regs->regs[53]) >> 32; | |
221 | al = (regs->regs[53]) & 0xffffffff; | |
222 | bh = (regs->regs[54]) >> 32; | |
223 | bl = (regs->regs[54]) & 0xffffffff; | |
224 | ch = (regs->regs[55]) >> 32; | |
225 | cl = (regs->regs[55]) & 0xffffffff; | |
226 | printk("R53 : %08Lx%08Lx R54 : %08Lx%08Lx R55 : %08Lx%08Lx\n", | |
227 | ah, al, bh, bl, ch, cl); | |
228 | ||
229 | ah = (regs->regs[56]) >> 32; | |
230 | al = (regs->regs[56]) & 0xffffffff; | |
231 | bh = (regs->regs[57]) >> 32; | |
232 | bl = (regs->regs[57]) & 0xffffffff; | |
233 | ch = (regs->regs[58]) >> 32; | |
234 | cl = (regs->regs[58]) & 0xffffffff; | |
235 | printk("R56 : %08Lx%08Lx R57 : %08Lx%08Lx R58 : %08Lx%08Lx\n", | |
236 | ah, al, bh, bl, ch, cl); | |
237 | ||
238 | ah = (regs->regs[59]) >> 32; | |
239 | al = (regs->regs[59]) & 0xffffffff; | |
240 | bh = (regs->regs[60]) >> 32; | |
241 | bl = (regs->regs[60]) & 0xffffffff; | |
242 | ch = (regs->regs[61]) >> 32; | |
243 | cl = (regs->regs[61]) & 0xffffffff; | |
244 | printk("R59 : %08Lx%08Lx R60 : %08Lx%08Lx R61 : %08Lx%08Lx\n", | |
245 | ah, al, bh, bl, ch, cl); | |
246 | ||
247 | ah = (regs->regs[62]) >> 32; | |
248 | al = (regs->regs[62]) & 0xffffffff; | |
249 | bh = (regs->tregs[0]) >> 32; | |
250 | bl = (regs->tregs[0]) & 0xffffffff; | |
251 | ch = (regs->tregs[1]) >> 32; | |
252 | cl = (regs->tregs[1]) & 0xffffffff; | |
253 | printk("R62 : %08Lx%08Lx T0 : %08Lx%08Lx T1 : %08Lx%08Lx\n", | |
254 | ah, al, bh, bl, ch, cl); | |
255 | ||
256 | ah = (regs->tregs[2]) >> 32; | |
257 | al = (regs->tregs[2]) & 0xffffffff; | |
258 | bh = (regs->tregs[3]) >> 32; | |
259 | bl = (regs->tregs[3]) & 0xffffffff; | |
260 | ch = (regs->tregs[4]) >> 32; | |
261 | cl = (regs->tregs[4]) & 0xffffffff; | |
262 | printk("T2 : %08Lx%08Lx T3 : %08Lx%08Lx T4 : %08Lx%08Lx\n", | |
263 | ah, al, bh, bl, ch, cl); | |
264 | ||
265 | ah = (regs->tregs[5]) >> 32; | |
266 | al = (regs->tregs[5]) & 0xffffffff; | |
267 | bh = (regs->tregs[6]) >> 32; | |
268 | bl = (regs->tregs[6]) & 0xffffffff; | |
269 | ch = (regs->tregs[7]) >> 32; | |
270 | cl = (regs->tregs[7]) & 0xffffffff; | |
271 | printk("T5 : %08Lx%08Lx T6 : %08Lx%08Lx T7 : %08Lx%08Lx\n", | |
272 | ah, al, bh, bl, ch, cl); | |
273 | ||
274 | /* | |
275 | * If we're in kernel mode, dump the stack too.. | |
276 | */ | |
277 | if (!user_mode(regs)) { | |
278 | void show_stack(struct task_struct *tsk, unsigned long *sp); | |
279 | unsigned long sp = regs->regs[15] & 0xffffffff; | |
280 | struct task_struct *tsk = get_current(); | |
281 | ||
282 | tsk->thread.kregs = regs; | |
283 | ||
284 | show_stack(tsk, (unsigned long *)sp); | |
285 | } | |
286 | } | |
287 | ||
1da177e4 LT |
288 | /* |
289 | * Free current thread data structures etc.. | |
290 | */ | |
e6464694 | 291 | void exit_thread(struct task_struct *tsk) |
1da177e4 | 292 | { |
a23ba435 PM |
293 | /* |
294 | * See arch/sparc/kernel/process.c for the precedent for doing | |
295 | * this -- RPC. | |
296 | * | |
297 | * The SH-5 FPU save/restore approach relies on | |
298 | * last_task_used_math pointing to a live task_struct. When | |
299 | * another task tries to use the FPU for the 1st time, the FPUDIS | |
300 | * trap handling (see arch/sh/kernel/cpu/sh5/fpu.c) will save the | |
301 | * existing FPU state to the FP regs field within | |
302 | * last_task_used_math before re-loading the new task's FPU state | |
303 | * (or initialising it if the FPU has been used before). So if | |
304 | * last_task_used_math is stale, and its page has already been | |
305 | * re-allocated for another use, the consequences are rather | |
306 | * grim. Unless we null it here, there is no other path through | |
307 | * which it would get safely nulled. | |
308 | */ | |
1da177e4 | 309 | #ifdef CONFIG_SH_FPU |
e6464694 | 310 | if (last_task_used_math == tsk) |
1da177e4 | 311 | last_task_used_math = NULL; |
1da177e4 LT |
312 | #endif |
313 | } | |
314 | ||
315 | void flush_thread(void) | |
316 | { | |
317 | ||
221af7f8 | 318 | /* Called by fs/exec.c (setup_new_exec) to remove traces of a |
1da177e4 LT |
319 | * previously running executable. */ |
320 | #ifdef CONFIG_SH_FPU | |
321 | if (last_task_used_math == current) { | |
322 | last_task_used_math = NULL; | |
323 | } | |
324 | /* Force FPU state to be reinitialised after exec */ | |
325 | clear_used_math(); | |
326 | #endif | |
327 | ||
328 | /* if we are a kernel thread, about to change to user thread, | |
329 | * update kreg | |
330 | */ | |
331 | if(current->thread.kregs==&fake_swapper_regs) { | |
332 | current->thread.kregs = | |
333 | ((struct pt_regs *)(THREAD_SIZE + (unsigned long) current) - 1); | |
334 | current->thread.uregs = current->thread.kregs; | |
335 | } | |
336 | } | |
337 | ||
338 | void release_thread(struct task_struct *dead_task) | |
339 | { | |
340 | /* do nothing */ | |
341 | } | |
342 | ||
343 | /* Fill in the fpu structure for a core dump.. */ | |
344 | int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu) | |
345 | { | |
346 | #ifdef CONFIG_SH_FPU | |
347 | int fpvalid; | |
348 | struct task_struct *tsk = current; | |
349 | ||
350 | fpvalid = !!tsk_used_math(tsk); | |
351 | if (fpvalid) { | |
352 | if (current == last_task_used_math) { | |
600ee240 | 353 | enable_fpu(); |
61cc7b0a | 354 | save_fpu(tsk); |
600ee240 | 355 | disable_fpu(); |
1da177e4 LT |
356 | last_task_used_math = 0; |
357 | regs->sr |= SR_FD; | |
358 | } | |
359 | ||
3ef2932b | 360 | memcpy(fpu, &tsk->thread.xstate->hardfpu, sizeof(*fpu)); |
1da177e4 LT |
361 | } |
362 | ||
363 | return fpvalid; | |
364 | #else | |
365 | return 0; /* Task didn't use the fpu at all. */ | |
366 | #endif | |
367 | } | |
4c978ca3 | 368 | EXPORT_SYMBOL(dump_fpu); |
1da177e4 LT |
369 | |
370 | asmlinkage void ret_from_fork(void); | |
7147e215 | 371 | asmlinkage void ret_from_kernel_thread(void); |
1da177e4 | 372 | |
6f2c55b8 | 373 | int copy_thread(unsigned long clone_flags, unsigned long usp, |
afa86fc4 | 374 | unsigned long arg, struct task_struct *p) |
1da177e4 | 375 | { |
8d28df81 | 376 | struct pt_regs *childregs; |
1da177e4 LT |
377 | |
378 | #ifdef CONFIG_SH_FPU | |
7147e215 AV |
379 | /* can't happen for a kernel thread */ |
380 | if (last_task_used_math == current) { | |
600ee240 | 381 | enable_fpu(); |
61cc7b0a | 382 | save_fpu(current); |
600ee240 | 383 | disable_fpu(); |
1da177e4 | 384 | last_task_used_math = NULL; |
0ad9513d | 385 | current_pt_regs()->sr |= SR_FD; |
1da177e4 LT |
386 | } |
387 | #endif | |
388 | /* Copy from sh version */ | |
ee8c1dd4 | 389 | childregs = (struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1; |
7147e215 | 390 | p->thread.sp = (unsigned long) childregs; |
1da177e4 | 391 | |
7147e215 AV |
392 | if (unlikely(p->flags & PF_KTHREAD)) { |
393 | memset(childregs, 0, sizeof(struct pt_regs)); | |
394 | childregs->regs[2] = (unsigned long)arg; | |
42b43341 | 395 | childregs->regs[3] = (unsigned long)usp; |
7147e215 AV |
396 | childregs->sr = (1 << 30); /* not user_mode */ |
397 | childregs->sr |= SR_FD; /* Invalidate FPU flag */ | |
398 | p->thread.pc = (unsigned long) ret_from_kernel_thread; | |
399 | return 0; | |
400 | } | |
0ad9513d | 401 | *childregs = *current_pt_regs(); |
1da177e4 | 402 | |
c7914834 PM |
403 | /* |
404 | * Sign extend the edited stack. | |
405 | * Note that thread.pc and thread.pc will stay | |
406 | * 32-bit wide and context switch must take care | |
407 | * of NEFF sign extension. | |
408 | */ | |
0ad9513d AV |
409 | if (usp) |
410 | childregs->regs[15] = neff_sign_extend(usp); | |
7147e215 | 411 | p->thread.uregs = childregs; |
1da177e4 LT |
412 | |
413 | childregs->regs[9] = 0; /* Set return value for child */ | |
414 | childregs->sr |= SR_FD; /* Invalidate FPU flag */ | |
415 | ||
1da177e4 LT |
416 | p->thread.pc = (unsigned long) ret_from_fork; |
417 | ||
1da177e4 LT |
418 | return 0; |
419 | } | |
420 | ||
43081e18 | 421 | #ifdef CONFIG_FRAME_POINTER |
1da177e4 LT |
422 | static int in_sh64_switch_to(unsigned long pc) |
423 | { | |
424 | extern char __sh64_switch_to_end; | |
425 | /* For a sleeping task, the PC is somewhere in the middle of the function, | |
426 | so we don't have to worry about masking the LSB off */ | |
427 | return (pc >= (unsigned long) sh64_switch_to) && | |
428 | (pc < (unsigned long) &__sh64_switch_to_end); | |
429 | } | |
43081e18 | 430 | #endif |
1da177e4 LT |
431 | |
432 | unsigned long get_wchan(struct task_struct *p) | |
433 | { | |
1da177e4 LT |
434 | unsigned long pc; |
435 | ||
436 | if (!p || p == current || p->state == TASK_RUNNING) | |
437 | return 0; | |
438 | ||
439 | /* | |
440 | * The same comment as on the Alpha applies here, too ... | |
441 | */ | |
442 | pc = thread_saved_pc(p); | |
443 | ||
444 | #ifdef CONFIG_FRAME_POINTER | |
445 | if (in_sh64_switch_to(pc)) { | |
43081e18 PM |
446 | unsigned long schedule_fp; |
447 | unsigned long sh64_switch_to_fp; | |
448 | unsigned long schedule_caller_pc; | |
449 | ||
1da177e4 LT |
450 | sh64_switch_to_fp = (long) p->thread.sp; |
451 | /* r14 is saved at offset 4 in the sh64_switch_to frame */ | |
452 | schedule_fp = *(unsigned long *) (long)(sh64_switch_to_fp + 4); | |
453 | ||
454 | /* and the caller of 'schedule' is (currently!) saved at offset 24 | |
455 | in the frame of schedule (from disasm) */ | |
456 | schedule_caller_pc = *(unsigned long *) (long)(schedule_fp + 24); | |
457 | return schedule_caller_pc; | |
458 | } | |
459 | #endif | |
460 | return pc; | |
461 | } |