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Some modifications to files needed to succesfully compile ;)
[wrt350n-kernel.git] / arch / sparc / kernel / process.c
blob19186ce8850d15768e8b322a8d3b5a2d79e1728b
1 /* linux/arch/sparc/kernel/process.c
2 *
3 * Copyright (C) 1995 David S. Miller (davem@davemloft.net)
4 * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
5 */
6
7 /*
8 * This file handles the architecture-dependent parts of process handling..
9 */
10
11 #include <stdarg.h>
12
13 #include <linux/errno.h>
14 #include <linux/module.h>
15 #include <linux/sched.h>
16 #include <linux/kernel.h>
17 #include <linux/kallsyms.h>
18 #include <linux/mm.h>
19 #include <linux/stddef.h>
20 #include <linux/ptrace.h>
21 #include <linux/slab.h>
22 #include <linux/user.h>
23 #include <linux/smp.h>
24 #include <linux/reboot.h>
25 #include <linux/delay.h>
26 #include <linux/pm.h>
27 #include <linux/init.h>
28
29 #include <asm/auxio.h>
30 #include <asm/oplib.h>
31 #include <asm/uaccess.h>
32 #include <asm/system.h>
33 #include <asm/page.h>
34 #include <asm/pgalloc.h>
35 #include <asm/pgtable.h>
36 #include <asm/delay.h>
37 #include <asm/processor.h>
38 #include <asm/psr.h>
39 #include <asm/elf.h>
40 #include <asm/prom.h>
41 #include <asm/unistd.h>
42
43 /*
44 * Power management idle function
45 * Set in pm platform drivers (apc.c and pmc.c)
46 */
47 void (*pm_idle)(void);
48
49 /*
50 * Power-off handler instantiation for pm.h compliance
51 * This is done via auxio, but could be used as a fallback
52 * handler when auxio is not present-- unused for now...
53 */
54 void (*pm_power_off)(void) = machine_power_off;
55 EXPORT_SYMBOL(pm_power_off);
56
57 /*
58 * sysctl - toggle power-off restriction for serial console
59 * systems in machine_power_off()
60 */
61 int scons_pwroff = 1;
62
63 extern void fpsave(unsigned long *, unsigned long *, void *, unsigned long *);
64
65 struct task_struct *last_task_used_math = NULL;
66 struct thread_info *current_set[NR_CPUS];
67
68 #ifndef CONFIG_SMP
69
70 #define SUN4C_FAULT_HIGH 100
71
72 /*
73 * the idle loop on a Sparc... ;)
74 */
75 void cpu_idle(void)
76 {
77 /* endless idle loop with no priority at all */
78 for (;;) {
79 if (ARCH_SUN4C_SUN4) {
80 static int count = HZ;
81 static unsigned long last_jiffies;
82 static unsigned long last_faults;
83 static unsigned long fps;
84 unsigned long now;
85 unsigned long faults;
86
87 extern unsigned long sun4c_kernel_faults;
88 extern void sun4c_grow_kernel_ring(void);
89
90 local_irq_disable();
91 now = jiffies;
92 count -= (now - last_jiffies);
93 last_jiffies = now;
94 if (count < 0) {
95 count += HZ;
96 faults = sun4c_kernel_faults;
97 fps = (fps + (faults - last_faults)) >> 1;
98 last_faults = faults;
99 #if 0
100 printk("kernel faults / second = %ld\n", fps);
101 #endif
102 if (fps >= SUN4C_FAULT_HIGH) {
103 sun4c_grow_kernel_ring();
104 }
105 }
106 local_irq_enable();
107 }
108
109 if (pm_idle) {
110 while (!need_resched())
111 (*pm_idle)();
112 } else {
113 while (!need_resched())
114 cpu_relax();
115 }
116 preempt_enable_no_resched();
117 schedule();
118 preempt_disable();
119 check_pgt_cache();
120 }
121 }
122
123 #else
124
125 /* This is being executed in task 0 'user space'. */
126 void cpu_idle(void)
127 {
128 set_thread_flag(TIF_POLLING_NRFLAG);
129 /* endless idle loop with no priority at all */
130 while(1) {
131 while (!need_resched())
132 cpu_relax();
133 preempt_enable_no_resched();
134 schedule();
135 preempt_disable();
136 check_pgt_cache();
137 }
138 }
139
140 #endif
141
142 extern char reboot_command [];
143
144 extern void (*prom_palette)(int);
145
146 /* XXX cli/sti -> local_irq_xxx here, check this works once SMP is fixed. */
147 void machine_halt(void)
148 {
149 local_irq_enable();
150 mdelay(8);
151 local_irq_disable();
152 if (prom_palette)
153 prom_palette (1);
154 prom_halt();
155 panic("Halt failed!");
156 }
157
158 void machine_restart(char * cmd)
159 {
160 char *p;
161
162 local_irq_enable();
163 mdelay(8);
164 local_irq_disable();
165
166 p = strchr (reboot_command, '\n');
167 if (p) *p = 0;
168 if (prom_palette)
169 prom_palette (1);
170 if (cmd)
171 prom_reboot(cmd);
172 if (*reboot_command)
173 prom_reboot(reboot_command);
174 prom_feval ("reset");
175 panic("Reboot failed!");
176 }
177
178 void machine_power_off(void)
179 {
180 #ifdef CONFIG_SUN_AUXIO
181 if (auxio_power_register &&
182 (strcmp(of_console_device->type, "serial") || scons_pwroff))
183 *auxio_power_register |= AUXIO_POWER_OFF;
184 #endif
185 machine_halt();
186 }
187
188 static DEFINE_SPINLOCK(sparc_backtrace_lock);
189
190 void __show_backtrace(unsigned long fp)
191 {
192 struct reg_window *rw;
193 unsigned long flags;
194 int cpu = smp_processor_id();
195
196 spin_lock_irqsave(&sparc_backtrace_lock, flags);
197
198 rw = (struct reg_window *)fp;
199 while(rw && (((unsigned long) rw) >= PAGE_OFFSET) &&
200 !(((unsigned long) rw) & 0x7)) {
201 printk("CPU[%d]: ARGS[%08lx,%08lx,%08lx,%08lx,%08lx,%08lx] "
202 "FP[%08lx] CALLER[%08lx]: ", cpu,
203 rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3],
204 rw->ins[4], rw->ins[5],
205 rw->ins[6],
206 rw->ins[7]);
207 print_symbol("%s\n", rw->ins[7]);
208 rw = (struct reg_window *) rw->ins[6];
209 }
210 spin_unlock_irqrestore(&sparc_backtrace_lock, flags);
211 }
212
213 #define __SAVE __asm__ __volatile__("save %sp, -0x40, %sp\n\t")
214 #define __RESTORE __asm__ __volatile__("restore %g0, %g0, %g0\n\t")
215 #define __GET_FP(fp) __asm__ __volatile__("mov %%i6, %0" : "=r" (fp))
216
217 void show_backtrace(void)
218 {
219 unsigned long fp;
220
221 __SAVE; __SAVE; __SAVE; __SAVE;
222 __SAVE; __SAVE; __SAVE; __SAVE;
223 __RESTORE; __RESTORE; __RESTORE; __RESTORE;
224 __RESTORE; __RESTORE; __RESTORE; __RESTORE;
225
226 __GET_FP(fp);
227
228 __show_backtrace(fp);
229 }
230
231 #ifdef CONFIG_SMP
232 void smp_show_backtrace_all_cpus(void)
233 {
234 xc0((smpfunc_t) show_backtrace);
235 show_backtrace();
236 }
237 #endif
238
239 #if 0
240 void show_stackframe(struct sparc_stackf *sf)
241 {
242 unsigned long size;
243 unsigned long *stk;
244 int i;
245
246 printk("l0: %08lx l1: %08lx l2: %08lx l3: %08lx "
247 "l4: %08lx l5: %08lx l6: %08lx l7: %08lx\n",
248 sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3],
249 sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
250 printk("i0: %08lx i1: %08lx i2: %08lx i3: %08lx "
251 "i4: %08lx i5: %08lx fp: %08lx i7: %08lx\n",
252 sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3],
253 sf->ins[4], sf->ins[5], (unsigned long)sf->fp, sf->callers_pc);
254 printk("sp: %08lx x0: %08lx x1: %08lx x2: %08lx "
255 "x3: %08lx x4: %08lx x5: %08lx xx: %08lx\n",
256 (unsigned long)sf->structptr, sf->xargs[0], sf->xargs[1],
257 sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
258 sf->xxargs[0]);
259 size = ((unsigned long)sf->fp) - ((unsigned long)sf);
260 size -= STACKFRAME_SZ;
261 stk = (unsigned long *)((unsigned long)sf + STACKFRAME_SZ);
262 i = 0;
263 do {
264 printk("s%d: %08lx\n", i++, *stk++);
265 } while ((size -= sizeof(unsigned long)));
266 }
267 #endif
268
269 void show_regs(struct pt_regs *r)
270 {
271 struct reg_window *rw = (struct reg_window *) r->u_regs[14];
272
273 printk("PSR: %08lx PC: %08lx NPC: %08lx Y: %08lx %s\n",
274 r->psr, r->pc, r->npc, r->y, print_tainted());
275 print_symbol("PC: <%s>\n", r->pc);
276 printk("%%G: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
277 r->u_regs[0], r->u_regs[1], r->u_regs[2], r->u_regs[3],
278 r->u_regs[4], r->u_regs[5], r->u_regs[6], r->u_regs[7]);
279 printk("%%O: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
280 r->u_regs[8], r->u_regs[9], r->u_regs[10], r->u_regs[11],
281 r->u_regs[12], r->u_regs[13], r->u_regs[14], r->u_regs[15]);
282 print_symbol("RPC: <%s>\n", r->u_regs[15]);
283
284 printk("%%L: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
285 rw->locals[0], rw->locals[1], rw->locals[2], rw->locals[3],
286 rw->locals[4], rw->locals[5], rw->locals[6], rw->locals[7]);
287 printk("%%I: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
288 rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3],
289 rw->ins[4], rw->ins[5], rw->ins[6], rw->ins[7]);
290 }
291
292 /*
293 * The show_stack is an external API which we do not use ourselves.
294 * The oops is printed in die_if_kernel.
295 */
296 void show_stack(struct task_struct *tsk, unsigned long *_ksp)
297 {
298 unsigned long pc, fp;
299 unsigned long task_base;
300 struct reg_window *rw;
301 int count = 0;
302
303 if (tsk != NULL)
304 task_base = (unsigned long) task_stack_page(tsk);
305 else
306 task_base = (unsigned long) current_thread_info();
307
308 fp = (unsigned long) _ksp;
309 do {
310 /* Bogus frame pointer? */
311 if (fp < (task_base + sizeof(struct thread_info)) ||
312 fp >= (task_base + (PAGE_SIZE << 1)))
313 break;
314 rw = (struct reg_window *) fp;
315 pc = rw->ins[7];
316 printk("[%08lx : ", pc);
317 print_symbol("%s ] ", pc);
318 fp = rw->ins[6];
319 } while (++count < 16);
320 printk("\n");
321 }
322
323 void dump_stack(void)
324 {
325 unsigned long *ksp;
326
327 __asm__ __volatile__("mov %%fp, %0"
328 : "=r" (ksp));
329 show_stack(current, ksp);
330 }
331
332 EXPORT_SYMBOL(dump_stack);
333
334 /*
335 * Note: sparc64 has a pretty intricated thread_saved_pc, check it out.
336 */
337 unsigned long thread_saved_pc(struct task_struct *tsk)
338 {
339 return task_thread_info(tsk)->kpc;
340 }
341
342 /*
343 * Free current thread data structures etc..
344 */
345 void exit_thread(void)
346 {
347 #ifndef CONFIG_SMP
348 if(last_task_used_math == current) {
349 #else
350 if (test_thread_flag(TIF_USEDFPU)) {
351 #endif
352 /* Keep process from leaving FPU in a bogon state. */
353 put_psr(get_psr() | PSR_EF);
354 fpsave(&current->thread.float_regs[0], &current->thread.fsr,
355 &current->thread.fpqueue[0], &current->thread.fpqdepth);
356 #ifndef CONFIG_SMP
357 last_task_used_math = NULL;
358 #else
359 clear_thread_flag(TIF_USEDFPU);
360 #endif
361 }
362 }
363
364 void flush_thread(void)
365 {
366 current_thread_info()->w_saved = 0;
367
368 /* No new signal delivery by default */
369 current->thread.new_signal = 0;
370 #ifndef CONFIG_SMP
371 if(last_task_used_math == current) {
372 #else
373 if (test_thread_flag(TIF_USEDFPU)) {
374 #endif
375 /* Clean the fpu. */
376 put_psr(get_psr() | PSR_EF);
377 fpsave(&current->thread.float_regs[0], &current->thread.fsr,
378 &current->thread.fpqueue[0], &current->thread.fpqdepth);
379 #ifndef CONFIG_SMP
380 last_task_used_math = NULL;
381 #else
382 clear_thread_flag(TIF_USEDFPU);
383 #endif
384 }
385
386 /* Now, this task is no longer a kernel thread. */
387 current->thread.current_ds = USER_DS;
388 if (current->thread.flags & SPARC_FLAG_KTHREAD) {
389 current->thread.flags &= ~SPARC_FLAG_KTHREAD;
390
391 /* We must fixup kregs as well. */
392 /* XXX This was not fixed for ti for a while, worked. Unused? */
393 current->thread.kregs = (struct pt_regs *)
394 (task_stack_page(current) + (THREAD_SIZE - TRACEREG_SZ));
395 }
396 }
397
398 static inline struct sparc_stackf __user *
399 clone_stackframe(struct sparc_stackf __user *dst,
400 struct sparc_stackf __user *src)
401 {
402 unsigned long size, fp;
403 struct sparc_stackf *tmp;
404 struct sparc_stackf __user *sp;
405
406 if (get_user(tmp, &src->fp))
407 return NULL;
408
409 fp = (unsigned long) tmp;
410 size = (fp - ((unsigned long) src));
411 fp = (unsigned long) dst;
412 sp = (struct sparc_stackf __user *)(fp - size);
413
414 /* do_fork() grabs the parent semaphore, we must release it
415 * temporarily so we can build the child clone stack frame
416 * without deadlocking.
417 */
418 if (__copy_user(sp, src, size))
419 sp = NULL;
420 else if (put_user(fp, &sp->fp))
421 sp = NULL;
422
423 return sp;
424 }
425
426 asmlinkage int sparc_do_fork(unsigned long clone_flags,
427 unsigned long stack_start,
428 struct pt_regs *regs,
429 unsigned long stack_size)
430 {
431 unsigned long parent_tid_ptr, child_tid_ptr;
432
433 parent_tid_ptr = regs->u_regs[UREG_I2];
434 child_tid_ptr = regs->u_regs[UREG_I4];
435
436 return do_fork(clone_flags, stack_start,
437 regs, stack_size,
438 (int __user *) parent_tid_ptr,
439 (int __user *) child_tid_ptr);
440 }
441
442 /* Copy a Sparc thread. The fork() return value conventions
443 * under SunOS are nothing short of bletcherous:
444 * Parent --> %o0 == childs pid, %o1 == 0
445 * Child --> %o0 == parents pid, %o1 == 1
446 *
447 * NOTE: We have a separate fork kpsr/kwim because
448 * the parent could change these values between
449 * sys_fork invocation and when we reach here
450 * if the parent should sleep while trying to
451 * allocate the task_struct and kernel stack in
452 * do_fork().
453 * XXX See comment above sys_vfork in sparc64. todo.
454 */
455 extern void ret_from_fork(void);
456
457 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
458 unsigned long unused,
459 struct task_struct *p, struct pt_regs *regs)
460 {
461 struct thread_info *ti = task_thread_info(p);
462 struct pt_regs *childregs;
463 char *new_stack;
464
465 #ifndef CONFIG_SMP
466 if(last_task_used_math == current) {
467 #else
468 if (test_thread_flag(TIF_USEDFPU)) {
469 #endif
470 put_psr(get_psr() | PSR_EF);
471 fpsave(&p->thread.float_regs[0], &p->thread.fsr,
472 &p->thread.fpqueue[0], &p->thread.fpqdepth);
473 #ifdef CONFIG_SMP
474 clear_thread_flag(TIF_USEDFPU);
475 #endif
476 }
477
478 /*
479 * p->thread_info new_stack childregs
480 * ! ! ! {if(PSR_PS) }
481 * V V (stk.fr.) V (pt_regs) { (stk.fr.) }
482 * +----- - - - - - ------+===========+============={+==========}+
483 */
484 new_stack = task_stack_page(p) + THREAD_SIZE;
485 if (regs->psr & PSR_PS)
486 new_stack -= STACKFRAME_SZ;
487 new_stack -= STACKFRAME_SZ + TRACEREG_SZ;
488 memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ);
489 childregs = (struct pt_regs *) (new_stack + STACKFRAME_SZ);
490
491 /*
492 * A new process must start with interrupts closed in 2.5,
493 * because this is how Mingo's scheduler works (see schedule_tail
494 * and finish_arch_switch). If we do not do it, a timer interrupt hits
495 * before we unlock, attempts to re-take the rq->lock, and then we die.
496 * Thus, kpsr|=PSR_PIL.
497 */
498 ti->ksp = (unsigned long) new_stack;
499 ti->kpc = (((unsigned long) ret_from_fork) - 0x8);
500 ti->kpsr = current->thread.fork_kpsr | PSR_PIL;
501 ti->kwim = current->thread.fork_kwim;
502
503 if(regs->psr & PSR_PS) {
504 extern struct pt_regs fake_swapper_regs;
505
506 p->thread.kregs = &fake_swapper_regs;
507 new_stack += STACKFRAME_SZ + TRACEREG_SZ;
508 childregs->u_regs[UREG_FP] = (unsigned long) new_stack;
509 p->thread.flags |= SPARC_FLAG_KTHREAD;
510 p->thread.current_ds = KERNEL_DS;
511 memcpy(new_stack, (void *)regs->u_regs[UREG_FP], STACKFRAME_SZ);
512 childregs->u_regs[UREG_G6] = (unsigned long) ti;
513 } else {
514 p->thread.kregs = childregs;
515 childregs->u_regs[UREG_FP] = sp;
516 p->thread.flags &= ~SPARC_FLAG_KTHREAD;
517 p->thread.current_ds = USER_DS;
518
519 if (sp != regs->u_regs[UREG_FP]) {
520 struct sparc_stackf __user *childstack;
521 struct sparc_stackf __user *parentstack;
522
523 /*
524 * This is a clone() call with supplied user stack.
525 * Set some valid stack frames to give to the child.
526 */
527 childstack = (struct sparc_stackf __user *)
528 (sp & ~0x7UL);
529 parentstack = (struct sparc_stackf __user *)
530 regs->u_regs[UREG_FP];
531
532 #if 0
533 printk("clone: parent stack:\n");
534 show_stackframe(parentstack);
535 #endif
536
537 childstack = clone_stackframe(childstack, parentstack);
538 if (!childstack)
539 return -EFAULT;
540
541 #if 0
542 printk("clone: child stack:\n");
543 show_stackframe(childstack);
544 #endif
545
546 childregs->u_regs[UREG_FP] = (unsigned long)childstack;
547 }
548 }
549
550 #ifdef CONFIG_SMP
551 /* FPU must be disabled on SMP. */
552 childregs->psr &= ~PSR_EF;
553 #endif
554
555 /* Set the return value for the child. */
556 childregs->u_regs[UREG_I0] = current->pid;
557 childregs->u_regs[UREG_I1] = 1;
558
559 /* Set the return value for the parent. */
560 regs->u_regs[UREG_I1] = 0;
561
562 if (clone_flags & CLONE_SETTLS)
563 childregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
564
565 return 0;
566 }
567
568 /*
569 * fill in the fpu structure for a core dump.
570 */
571 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
572 {
573 if (used_math()) {
574 memset(fpregs, 0, sizeof(*fpregs));
575 fpregs->pr_q_entrysize = 8;
576 return 1;
577 }
578 #ifdef CONFIG_SMP
579 if (test_thread_flag(TIF_USEDFPU)) {
580 put_psr(get_psr() | PSR_EF);
581 fpsave(&current->thread.float_regs[0], &current->thread.fsr,
582 &current->thread.fpqueue[0], &current->thread.fpqdepth);
583 if (regs != NULL) {
584 regs->psr &= ~(PSR_EF);
585 clear_thread_flag(TIF_USEDFPU);
586 }
587 }
588 #else
589 if (current == last_task_used_math) {
590 put_psr(get_psr() | PSR_EF);
591 fpsave(&current->thread.float_regs[0], &current->thread.fsr,
592 &current->thread.fpqueue[0], &current->thread.fpqdepth);
593 if (regs != NULL) {
594 regs->psr &= ~(PSR_EF);
595 last_task_used_math = NULL;
596 }
597 }
598 #endif
599 memcpy(&fpregs->pr_fr.pr_regs[0],
600 &current->thread.float_regs[0],
601 (sizeof(unsigned long) * 32));
602 fpregs->pr_fsr = current->thread.fsr;
603 fpregs->pr_qcnt = current->thread.fpqdepth;
604 fpregs->pr_q_entrysize = 8;
605 fpregs->pr_en = 1;
606 if(fpregs->pr_qcnt != 0) {
607 memcpy(&fpregs->pr_q[0],
608 &current->thread.fpqueue[0],
609 sizeof(struct fpq) * fpregs->pr_qcnt);
610 }
611 /* Zero out the rest. */
612 memset(&fpregs->pr_q[fpregs->pr_qcnt], 0,
613 sizeof(struct fpq) * (32 - fpregs->pr_qcnt));
614 return 1;
615 }
616
617 /*
618 * sparc_execve() executes a new program after the asm stub has set
619 * things up for us. This should basically do what I want it to.
620 */
621 asmlinkage int sparc_execve(struct pt_regs *regs)
622 {
623 int error, base = 0;
624 char *filename;
625
626 /* Check for indirect call. */
627 if(regs->u_regs[UREG_G1] == 0)
628 base = 1;
629
630 filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
631 error = PTR_ERR(filename);
632 if(IS_ERR(filename))
633 goto out;
634 error = do_execve(filename,
635 (char __user * __user *)regs->u_regs[base + UREG_I1],
636 (char __user * __user *)regs->u_regs[base + UREG_I2],
637 regs);
638 putname(filename);
639 if (error == 0) {
640 task_lock(current);
641 current->ptrace &= ~PT_DTRACE;
642 task_unlock(current);
643 }
644 out:
645 return error;
646 }
647
648 /*
649 * This is the mechanism for creating a new kernel thread.
650 *
651 * NOTE! Only a kernel-only process(ie the swapper or direct descendants
652 * who haven't done an "execve()") should use this: it will work within
653 * a system call from a "real" process, but the process memory space will
654 * not be freed until both the parent and the child have exited.
655 */
656 pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
657 {
658 long retval;
659
660 __asm__ __volatile__("mov %4, %%g2\n\t" /* Set aside fn ptr... */
661 "mov %5, %%g3\n\t" /* and arg. */
662 "mov %1, %%g1\n\t"
663 "mov %2, %%o0\n\t" /* Clone flags. */
664 "mov 0, %%o1\n\t" /* usp arg == 0 */
665 "t 0x10\n\t" /* Linux/Sparc clone(). */
666 "cmp %%o1, 0\n\t"
667 "be 1f\n\t" /* The parent, just return. */
668 " nop\n\t" /* Delay slot. */
669 "jmpl %%g2, %%o7\n\t" /* Call the function. */
670 " mov %%g3, %%o0\n\t" /* Get back the arg in delay. */
671 "mov %3, %%g1\n\t"
672 "t 0x10\n\t" /* Linux/Sparc exit(). */
673 /* Notreached by child. */
674 "1: mov %%o0, %0\n\t" :
675 "=r" (retval) :
676 "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
677 "i" (__NR_exit), "r" (fn), "r" (arg) :
678 "g1", "g2", "g3", "o0", "o1", "memory", "cc");
679 return retval;
680 }
681
682 unsigned long get_wchan(struct task_struct *task)
683 {
684 unsigned long pc, fp, bias = 0;
685 unsigned long task_base = (unsigned long) task;
686 unsigned long ret = 0;
687 struct reg_window *rw;
688 int count = 0;
689
690 if (!task || task == current ||
691 task->state == TASK_RUNNING)
692 goto out;
693
694 fp = task_thread_info(task)->ksp + bias;
695 do {
696 /* Bogus frame pointer? */
697 if (fp < (task_base + sizeof(struct thread_info)) ||
698 fp >= (task_base + (2 * PAGE_SIZE)))
699 break;
700 rw = (struct reg_window *) fp;
701 pc = rw->ins[7];
702 if (!in_sched_functions(pc)) {
703 ret = pc;
704 goto out;
705 }
706 fp = rw->ins[6] + bias;
707 } while (++count < 16);
708
709 out:
710 return ret;
711 }
712
WRT350N Kernel Patches