1 /* arch/sparc64/kernel/process.c
3 * Copyright (C) 1995, 1996, 2008 David S. Miller (davem@davemloft.net)
4 * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
5 * Copyright (C) 1997, 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
9 * This file handles the architecture-dependent parts of process handling..
14 #include <linux/errno.h>
15 #include <linux/export.h>
16 #include <linux/sched.h>
17 #include <linux/kernel.h>
20 #include <linux/smp.h>
21 #include <linux/stddef.h>
22 #include <linux/ptrace.h>
23 #include <linux/slab.h>
24 #include <linux/user.h>
25 #include <linux/delay.h>
26 #include <linux/compat.h>
27 #include <linux/tick.h>
28 #include <linux/init.h>
29 #include <linux/cpu.h>
30 #include <linux/elfcore.h>
31 #include <linux/sysrq.h>
32 #include <linux/nmi.h>
34 #include <asm/uaccess.h>
35 #include <asm/system.h>
37 #include <asm/pgalloc.h>
38 #include <asm/pgtable.h>
39 #include <asm/processor.h>
40 #include <asm/pstate.h>
42 #include <asm/fpumacro.h>
44 #include <asm/cpudata.h>
45 #include <asm/mmu_context.h>
46 #include <asm/unistd.h>
47 #include <asm/hypervisor.h>
48 #include <asm/syscalls.h>
49 #include <asm/irq_regs.h>
54 static void sparc64_yield(int cpu
)
56 if (tlb_type
!= hypervisor
) {
61 clear_thread_flag(TIF_POLLING_NRFLAG
);
62 smp_mb__after_clear_bit();
64 while (!need_resched() && !cpu_is_offline(cpu
)) {
67 /* Disable interrupts. */
69 "rdpr %%pstate, %0\n\t"
71 "wrpr %0, %%g0, %%pstate"
75 if (!need_resched() && !cpu_is_offline(cpu
))
78 /* Re-enable interrupts. */
80 "rdpr %%pstate, %0\n\t"
82 "wrpr %0, %%g0, %%pstate"
87 set_thread_flag(TIF_POLLING_NRFLAG
);
90 /* The idle loop on sparc64. */
93 int cpu
= smp_processor_id();
95 set_thread_flag(TIF_POLLING_NRFLAG
);
98 tick_nohz_stop_sched_tick(1);
100 while (!need_resched() && !cpu_is_offline(cpu
))
103 tick_nohz_restart_sched_tick();
105 preempt_enable_no_resched();
107 #ifdef CONFIG_HOTPLUG_CPU
108 if (cpu_is_offline(cpu
))
118 static void show_regwindow32(struct pt_regs
*regs
)
120 struct reg_window32 __user
*rw
;
121 struct reg_window32 r_w
;
124 __asm__
__volatile__ ("flushw");
125 rw
= compat_ptr((unsigned)regs
->u_regs
[14]);
128 if (copy_from_user (&r_w
, rw
, sizeof(r_w
))) {
134 printk("l0: %08x l1: %08x l2: %08x l3: %08x "
135 "l4: %08x l5: %08x l6: %08x l7: %08x\n",
136 r_w
.locals
[0], r_w
.locals
[1], r_w
.locals
[2], r_w
.locals
[3],
137 r_w
.locals
[4], r_w
.locals
[5], r_w
.locals
[6], r_w
.locals
[7]);
138 printk("i0: %08x i1: %08x i2: %08x i3: %08x "
139 "i4: %08x i5: %08x i6: %08x i7: %08x\n",
140 r_w
.ins
[0], r_w
.ins
[1], r_w
.ins
[2], r_w
.ins
[3],
141 r_w
.ins
[4], r_w
.ins
[5], r_w
.ins
[6], r_w
.ins
[7]);
144 #define show_regwindow32(regs) do { } while (0)
147 static void show_regwindow(struct pt_regs
*regs
)
149 struct reg_window __user
*rw
;
150 struct reg_window
*rwk
;
151 struct reg_window r_w
;
154 if ((regs
->tstate
& TSTATE_PRIV
) || !(test_thread_flag(TIF_32BIT
))) {
155 __asm__
__volatile__ ("flushw");
156 rw
= (struct reg_window __user
*)
157 (regs
->u_regs
[14] + STACK_BIAS
);
158 rwk
= (struct reg_window
*)
159 (regs
->u_regs
[14] + STACK_BIAS
);
160 if (!(regs
->tstate
& TSTATE_PRIV
)) {
163 if (copy_from_user (&r_w
, rw
, sizeof(r_w
))) {
171 show_regwindow32(regs
);
174 printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
175 rwk
->locals
[0], rwk
->locals
[1], rwk
->locals
[2], rwk
->locals
[3]);
176 printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
177 rwk
->locals
[4], rwk
->locals
[5], rwk
->locals
[6], rwk
->locals
[7]);
178 printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
179 rwk
->ins
[0], rwk
->ins
[1], rwk
->ins
[2], rwk
->ins
[3]);
180 printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
181 rwk
->ins
[4], rwk
->ins
[5], rwk
->ins
[6], rwk
->ins
[7]);
182 if (regs
->tstate
& TSTATE_PRIV
)
183 printk("I7: <%pS>\n", (void *) rwk
->ins
[7]);
186 void show_regs(struct pt_regs
*regs
)
188 printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x %s\n", regs
->tstate
,
189 regs
->tpc
, regs
->tnpc
, regs
->y
, print_tainted());
190 printk("TPC: <%pS>\n", (void *) regs
->tpc
);
191 printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
192 regs
->u_regs
[0], regs
->u_regs
[1], regs
->u_regs
[2],
194 printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
195 regs
->u_regs
[4], regs
->u_regs
[5], regs
->u_regs
[6],
197 printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
198 regs
->u_regs
[8], regs
->u_regs
[9], regs
->u_regs
[10],
200 printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
201 regs
->u_regs
[12], regs
->u_regs
[13], regs
->u_regs
[14],
203 printk("RPC: <%pS>\n", (void *) regs
->u_regs
[15]);
204 show_regwindow(regs
);
205 show_stack(current
, (unsigned long *) regs
->u_regs
[UREG_FP
]);
208 struct global_reg_snapshot global_reg_snapshot
[NR_CPUS
];
209 static DEFINE_SPINLOCK(global_reg_snapshot_lock
);
211 static void __global_reg_self(struct thread_info
*tp
, struct pt_regs
*regs
,
216 global_reg_snapshot
[this_cpu
].tstate
= regs
->tstate
;
217 global_reg_snapshot
[this_cpu
].tpc
= regs
->tpc
;
218 global_reg_snapshot
[this_cpu
].tnpc
= regs
->tnpc
;
219 global_reg_snapshot
[this_cpu
].o7
= regs
->u_regs
[UREG_I7
];
221 if (regs
->tstate
& TSTATE_PRIV
) {
222 struct reg_window
*rw
;
224 rw
= (struct reg_window
*)
225 (regs
->u_regs
[UREG_FP
] + STACK_BIAS
);
226 if (kstack_valid(tp
, (unsigned long) rw
)) {
227 global_reg_snapshot
[this_cpu
].i7
= rw
->ins
[7];
228 rw
= (struct reg_window
*)
229 (rw
->ins
[6] + STACK_BIAS
);
230 if (kstack_valid(tp
, (unsigned long) rw
))
231 global_reg_snapshot
[this_cpu
].rpc
= rw
->ins
[7];
234 global_reg_snapshot
[this_cpu
].i7
= 0;
235 global_reg_snapshot
[this_cpu
].rpc
= 0;
237 global_reg_snapshot
[this_cpu
].thread
= tp
;
240 /* In order to avoid hangs we do not try to synchronize with the
241 * global register dump client cpus. The last store they make is to
242 * the thread pointer, so do a short poll waiting for that to become
245 static void __global_reg_poll(struct global_reg_snapshot
*gp
)
249 while (!gp
->thread
&& ++limit
< 100) {
255 void arch_trigger_all_cpu_backtrace(void)
257 struct thread_info
*tp
= current_thread_info();
258 struct pt_regs
*regs
= get_irq_regs();
265 spin_lock_irqsave(&global_reg_snapshot_lock
, flags
);
267 memset(global_reg_snapshot
, 0, sizeof(global_reg_snapshot
));
269 this_cpu
= raw_smp_processor_id();
271 __global_reg_self(tp
, regs
, this_cpu
);
273 smp_fetch_global_regs();
275 for_each_online_cpu(cpu
) {
276 struct global_reg_snapshot
*gp
= &global_reg_snapshot
[cpu
];
278 __global_reg_poll(gp
);
281 printk("%c CPU[%3d]: TSTATE[%016lx] TPC[%016lx] TNPC[%016lx] TASK[%s:%d]\n",
282 (cpu
== this_cpu
? '*' : ' '), cpu
,
283 gp
->tstate
, gp
->tpc
, gp
->tnpc
,
284 ((tp
&& tp
->task
) ? tp
->task
->comm
: "NULL"),
285 ((tp
&& tp
->task
) ? tp
->task
->pid
: -1));
287 if (gp
->tstate
& TSTATE_PRIV
) {
288 printk(" TPC[%pS] O7[%pS] I7[%pS] RPC[%pS]\n",
294 printk(" TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
295 gp
->tpc
, gp
->o7
, gp
->i7
, gp
->rpc
);
299 memset(global_reg_snapshot
, 0, sizeof(global_reg_snapshot
));
301 spin_unlock_irqrestore(&global_reg_snapshot_lock
, flags
);
304 #ifdef CONFIG_MAGIC_SYSRQ
306 static void sysrq_handle_globreg(int key
)
308 arch_trigger_all_cpu_backtrace();
311 static struct sysrq_key_op sparc_globalreg_op
= {
312 .handler
= sysrq_handle_globreg
,
313 .help_msg
= "Globalregs",
314 .action_msg
= "Show Global CPU Regs",
317 static int __init
sparc_globreg_init(void)
319 return register_sysrq_key('y', &sparc_globalreg_op
);
322 core_initcall(sparc_globreg_init
);
326 unsigned long thread_saved_pc(struct task_struct
*tsk
)
328 struct thread_info
*ti
= task_thread_info(tsk
);
329 unsigned long ret
= 0xdeadbeefUL
;
333 sp
= (unsigned long *)(ti
->ksp
+ STACK_BIAS
);
334 if (((unsigned long)sp
& (sizeof(long) - 1)) == 0UL &&
337 fp
= (unsigned long *)(sp
[14] + STACK_BIAS
);
338 if (((unsigned long)fp
& (sizeof(long) - 1)) == 0UL)
345 /* Free current thread data structures etc.. */
346 void exit_thread(void)
348 struct thread_info
*t
= current_thread_info();
351 if (t
->utraps
[0] < 2)
358 void flush_thread(void)
360 struct thread_info
*t
= current_thread_info();
361 struct mm_struct
*mm
;
365 tsb_context_switch(mm
);
367 set_thread_wsaved(0);
369 /* Clear FPU register state. */
372 if (get_thread_current_ds() != ASI_AIUS
)
376 /* It's a bit more tricky when 64-bit tasks are involved... */
377 static unsigned long clone_stackframe(unsigned long csp
, unsigned long psp
)
379 unsigned long fp
, distance
, rval
;
381 if (!(test_thread_flag(TIF_32BIT
))) {
384 __get_user(fp
, &(((struct reg_window __user
*)psp
)->ins
[6]));
387 __get_user(fp
, &(((struct reg_window32 __user
*)psp
)->ins
[6]));
389 /* Now align the stack as this is mandatory in the Sparc ABI
390 * due to how register windows work. This hides the
391 * restriction from thread libraries etc.
396 rval
= (csp
- distance
);
397 if (copy_in_user((void __user
*) rval
, (void __user
*) psp
, distance
))
399 else if (test_thread_flag(TIF_32BIT
)) {
400 if (put_user(((u32
)csp
),
401 &(((struct reg_window32 __user
*)rval
)->ins
[6])))
404 if (put_user(((u64
)csp
- STACK_BIAS
),
405 &(((struct reg_window __user
*)rval
)->ins
[6])))
408 rval
= rval
- STACK_BIAS
;
414 /* Standard stuff. */
415 static inline void shift_window_buffer(int first_win
, int last_win
,
416 struct thread_info
*t
)
420 for (i
= first_win
; i
< last_win
; i
++) {
421 t
->rwbuf_stkptrs
[i
] = t
->rwbuf_stkptrs
[i
+1];
422 memcpy(&t
->reg_window
[i
], &t
->reg_window
[i
+1],
423 sizeof(struct reg_window
));
427 void synchronize_user_stack(void)
429 struct thread_info
*t
= current_thread_info();
430 unsigned long window
;
432 flush_user_windows();
433 if ((window
= get_thread_wsaved()) != 0) {
434 int winsize
= sizeof(struct reg_window
);
437 if (test_thread_flag(TIF_32BIT
))
438 winsize
= sizeof(struct reg_window32
);
444 unsigned long sp
= (t
->rwbuf_stkptrs
[window
] + bias
);
445 struct reg_window
*rwin
= &t
->reg_window
[window
];
447 if (!copy_to_user((char __user
*)sp
, rwin
, winsize
)) {
448 shift_window_buffer(window
, get_thread_wsaved() - 1, t
);
449 set_thread_wsaved(get_thread_wsaved() - 1);
455 static void stack_unaligned(unsigned long sp
)
459 info
.si_signo
= SIGBUS
;
461 info
.si_code
= BUS_ADRALN
;
462 info
.si_addr
= (void __user
*) sp
;
464 force_sig_info(SIGBUS
, &info
, current
);
467 void fault_in_user_windows(void)
469 struct thread_info
*t
= current_thread_info();
470 unsigned long window
;
471 int winsize
= sizeof(struct reg_window
);
474 if (test_thread_flag(TIF_32BIT
))
475 winsize
= sizeof(struct reg_window32
);
479 flush_user_windows();
480 window
= get_thread_wsaved();
482 if (likely(window
!= 0)) {
485 unsigned long sp
= (t
->rwbuf_stkptrs
[window
] + bias
);
486 struct reg_window
*rwin
= &t
->reg_window
[window
];
488 if (unlikely(sp
& 0x7UL
))
491 if (unlikely(copy_to_user((char __user
*)sp
,
496 set_thread_wsaved(0);
500 set_thread_wsaved(window
+ 1);
504 asmlinkage
long sparc_do_fork(unsigned long clone_flags
,
505 unsigned long stack_start
,
506 struct pt_regs
*regs
,
507 unsigned long stack_size
)
509 int __user
*parent_tid_ptr
, *child_tid_ptr
;
510 unsigned long orig_i1
= regs
->u_regs
[UREG_I1
];
514 if (test_thread_flag(TIF_32BIT
)) {
515 parent_tid_ptr
= compat_ptr(regs
->u_regs
[UREG_I2
]);
516 child_tid_ptr
= compat_ptr(regs
->u_regs
[UREG_I4
]);
520 parent_tid_ptr
= (int __user
*) regs
->u_regs
[UREG_I2
];
521 child_tid_ptr
= (int __user
*) regs
->u_regs
[UREG_I4
];
524 ret
= do_fork(clone_flags
, stack_start
,
526 parent_tid_ptr
, child_tid_ptr
);
528 /* If we get an error and potentially restart the system
529 * call, we're screwed because copy_thread() clobbered
530 * the parent's %o1. So detect that case and restore it
533 if ((unsigned long)ret
>= -ERESTART_RESTARTBLOCK
)
534 regs
->u_regs
[UREG_I1
] = orig_i1
;
539 /* Copy a Sparc thread. The fork() return value conventions
540 * under SunOS are nothing short of bletcherous:
541 * Parent --> %o0 == childs pid, %o1 == 0
542 * Child --> %o0 == parents pid, %o1 == 1
544 int copy_thread(unsigned long clone_flags
, unsigned long sp
,
545 unsigned long unused
,
546 struct task_struct
*p
, struct pt_regs
*regs
)
548 struct thread_info
*t
= task_thread_info(p
);
549 struct sparc_stackf
*parent_sf
;
550 unsigned long child_stack_sz
;
551 char *child_trap_frame
;
554 kernel_thread
= (regs
->tstate
& TSTATE_PRIV
) ? 1 : 0;
555 parent_sf
= ((struct sparc_stackf
*) regs
) - 1;
557 /* Calculate offset to stack_frame & pt_regs */
558 child_stack_sz
= ((STACKFRAME_SZ
+ TRACEREG_SZ
) +
559 (kernel_thread
? STACKFRAME_SZ
: 0));
560 child_trap_frame
= (task_stack_page(p
) +
561 (THREAD_SIZE
- child_stack_sz
));
562 memcpy(child_trap_frame
, parent_sf
, child_stack_sz
);
564 t
->flags
= (t
->flags
& ~((0xffUL
<< TI_FLAG_CWP_SHIFT
) |
565 (0xffUL
<< TI_FLAG_CURRENT_DS_SHIFT
))) |
566 (((regs
->tstate
+ 1) & TSTATE_CWP
) << TI_FLAG_CWP_SHIFT
);
568 t
->ksp
= ((unsigned long) child_trap_frame
) - STACK_BIAS
;
569 t
->kregs
= (struct pt_regs
*) (child_trap_frame
+
570 sizeof(struct sparc_stackf
));
574 struct sparc_stackf
*child_sf
= (struct sparc_stackf
*)
575 (child_trap_frame
+ (STACKFRAME_SZ
+ TRACEREG_SZ
));
577 /* Zero terminate the stack backtrace. */
579 t
->kregs
->u_regs
[UREG_FP
] =
580 ((unsigned long) child_sf
) - STACK_BIAS
;
582 t
->flags
|= ((long)ASI_P
<< TI_FLAG_CURRENT_DS_SHIFT
);
583 t
->kregs
->u_regs
[UREG_G6
] = (unsigned long) t
;
584 t
->kregs
->u_regs
[UREG_G4
] = (unsigned long) t
->task
;
586 if (t
->flags
& _TIF_32BIT
) {
587 sp
&= 0x00000000ffffffffUL
;
588 regs
->u_regs
[UREG_FP
] &= 0x00000000ffffffffUL
;
590 t
->kregs
->u_regs
[UREG_FP
] = sp
;
591 t
->flags
|= ((long)ASI_AIUS
<< TI_FLAG_CURRENT_DS_SHIFT
);
592 if (sp
!= regs
->u_regs
[UREG_FP
]) {
595 csp
= clone_stackframe(sp
, regs
->u_regs
[UREG_FP
]);
598 t
->kregs
->u_regs
[UREG_FP
] = csp
;
604 /* Set the return value for the child. */
605 t
->kregs
->u_regs
[UREG_I0
] = current
->pid
;
606 t
->kregs
->u_regs
[UREG_I1
] = 1;
608 /* Set the second return value for the parent. */
609 regs
->u_regs
[UREG_I1
] = 0;
611 if (clone_flags
& CLONE_SETTLS
)
612 t
->kregs
->u_regs
[UREG_G7
] = regs
->u_regs
[UREG_I3
];
618 * This is the mechanism for creating a new kernel thread.
620 * NOTE! Only a kernel-only process(ie the swapper or direct descendants
621 * who haven't done an "execve()") should use this: it will work within
622 * a system call from a "real" process, but the process memory space will
623 * not be freed until both the parent and the child have exited.
625 pid_t
kernel_thread(int (*fn
)(void *), void * arg
, unsigned long flags
)
629 /* If the parent runs before fn(arg) is called by the child,
630 * the input registers of this function can be clobbered.
631 * So we stash 'fn' and 'arg' into global registers which
632 * will not be modified by the parent.
634 __asm__
__volatile__("mov %4, %%g2\n\t" /* Save FN into global */
635 "mov %5, %%g3\n\t" /* Save ARG into global */
636 "mov %1, %%g1\n\t" /* Clone syscall nr. */
637 "mov %2, %%o0\n\t" /* Clone flags. */
638 "mov 0, %%o1\n\t" /* usp arg == 0 */
639 "t 0x6d\n\t" /* Linux/Sparc clone(). */
640 "brz,a,pn %%o1, 1f\n\t" /* Parent, just return. */
642 "jmpl %%g2, %%o7\n\t" /* Call the function. */
643 " mov %%g3, %%o0\n\t" /* Set arg in delay. */
645 "t 0x6d\n\t" /* Linux/Sparc exit(). */
646 /* Notreached by child. */
649 "i" (__NR_clone
), "r" (flags
| CLONE_VM
| CLONE_UNTRACED
),
650 "i" (__NR_exit
), "r" (fn
), "r" (arg
) :
651 "g1", "g2", "g3", "o0", "o1", "memory", "cc");
654 EXPORT_SYMBOL(kernel_thread
);
658 unsigned int pr_regs
[32];
659 unsigned long pr_dregs
[16];
661 unsigned int __unused
;
663 unsigned char pr_qcnt
;
664 unsigned char pr_q_entrysize
;
666 unsigned int pr_q
[64];
670 * fill in the fpu structure for a core dump.
672 int dump_fpu (struct pt_regs
* regs
, elf_fpregset_t
* fpregs
)
674 unsigned long *kfpregs
= current_thread_info()->fpregs
;
675 unsigned long fprs
= current_thread_info()->fpsaved
[0];
677 if (test_thread_flag(TIF_32BIT
)) {
678 elf_fpregset_t32
*fpregs32
= (elf_fpregset_t32
*)fpregs
;
681 memcpy(&fpregs32
->pr_fr
.pr_regs
[0], kfpregs
,
682 sizeof(unsigned int) * 32);
684 memset(&fpregs32
->pr_fr
.pr_regs
[0], 0,
685 sizeof(unsigned int) * 32);
686 fpregs32
->pr_qcnt
= 0;
687 fpregs32
->pr_q_entrysize
= 8;
688 memset(&fpregs32
->pr_q
[0], 0,
689 (sizeof(unsigned int) * 64));
690 if (fprs
& FPRS_FEF
) {
691 fpregs32
->pr_fsr
= (unsigned int) current_thread_info()->xfsr
[0];
694 fpregs32
->pr_fsr
= 0;
699 memcpy(&fpregs
->pr_regs
[0], kfpregs
,
700 sizeof(unsigned int) * 32);
702 memset(&fpregs
->pr_regs
[0], 0,
703 sizeof(unsigned int) * 32);
705 memcpy(&fpregs
->pr_regs
[16], kfpregs
+16,
706 sizeof(unsigned int) * 32);
708 memset(&fpregs
->pr_regs
[16], 0,
709 sizeof(unsigned int) * 32);
710 if(fprs
& FPRS_FEF
) {
711 fpregs
->pr_fsr
= current_thread_info()->xfsr
[0];
712 fpregs
->pr_gsr
= current_thread_info()->gsr
[0];
714 fpregs
->pr_fsr
= fpregs
->pr_gsr
= 0;
716 fpregs
->pr_fprs
= fprs
;
720 EXPORT_SYMBOL(dump_fpu
);
723 * sparc_execve() executes a new program after the asm stub has set
724 * things up for us. This should basically do what I want it to.
726 asmlinkage
int sparc_execve(struct pt_regs
*regs
)
731 /* User register window flush is done by entry.S */
733 /* Check for indirect call. */
734 if (regs
->u_regs
[UREG_G1
] == 0)
737 filename
= getname((char __user
*)regs
->u_regs
[base
+ UREG_I0
]);
738 error
= PTR_ERR(filename
);
739 if (IS_ERR(filename
))
741 error
= do_execve(filename
,
742 (const char __user
*const __user
*)
743 regs
->u_regs
[base
+ UREG_I1
],
744 (const char __user
*const __user
*)
745 regs
->u_regs
[base
+ UREG_I2
], regs
);
749 current_thread_info()->xfsr
[0] = 0;
750 current_thread_info()->fpsaved
[0] = 0;
751 regs
->tstate
&= ~TSTATE_PEF
;
757 unsigned long get_wchan(struct task_struct
*task
)
759 unsigned long pc
, fp
, bias
= 0;
760 struct thread_info
*tp
;
761 struct reg_window
*rw
;
762 unsigned long ret
= 0;
765 if (!task
|| task
== current
||
766 task
->state
== TASK_RUNNING
)
769 tp
= task_thread_info(task
);
771 fp
= task_thread_info(task
)->ksp
+ bias
;
774 if (!kstack_valid(tp
, fp
))
776 rw
= (struct reg_window
*) fp
;
778 if (!in_sched_functions(pc
)) {
782 fp
= rw
->ins
[6] + bias
;
783 } while (++count
< 16);