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/perf_event.h>
31 #include <linux/elfcore.h>
32 #include <linux/sysrq.h>
33 #include <linux/nmi.h>
35 #include <asm/uaccess.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>
55 static void sparc64_yield(int cpu)
57 if (tlb_type != hypervisor) {
62 clear_thread_flag(TIF_POLLING_NRFLAG);
63 smp_mb__after_clear_bit();
65 while (!need_resched() && !cpu_is_offline(cpu)) {
68 /* Disable interrupts. */
70 "rdpr %%pstate, %0\n\t"
72 "wrpr %0, %%g0, %%pstate"
76 if (!need_resched() && !cpu_is_offline(cpu))
79 /* Re-enable interrupts. */
81 "rdpr %%pstate, %0\n\t"
83 "wrpr %0, %%g0, %%pstate"
88 set_thread_flag(TIF_POLLING_NRFLAG);
91 /* The idle loop on sparc64. */
94 int cpu = smp_processor_id();
96 set_thread_flag(TIF_POLLING_NRFLAG);
99 tick_nohz_idle_enter();
102 while (!need_resched() && !cpu_is_offline(cpu))
106 tick_nohz_idle_exit();
108 #ifdef CONFIG_HOTPLUG_CPU
109 if (cpu_is_offline(cpu)) {
110 sched_preempt_enable_no_resched();
114 schedule_preempt_disabled();
119 static void show_regwindow32(struct pt_regs *regs)
121 struct reg_window32 __user *rw;
122 struct reg_window32 r_w;
125 __asm__ __volatile__ ("flushw");
126 rw = compat_ptr((unsigned)regs->u_regs[14]);
129 if (copy_from_user (&r_w, rw, sizeof(r_w))) {
135 printk("l0: %08x l1: %08x l2: %08x l3: %08x "
136 "l4: %08x l5: %08x l6: %08x l7: %08x\n",
137 r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
138 r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
139 printk("i0: %08x i1: %08x i2: %08x i3: %08x "
140 "i4: %08x i5: %08x i6: %08x i7: %08x\n",
141 r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
142 r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
145 #define show_regwindow32(regs) do { } while (0)
148 static void show_regwindow(struct pt_regs *regs)
150 struct reg_window __user *rw;
151 struct reg_window *rwk;
152 struct reg_window r_w;
155 if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
156 __asm__ __volatile__ ("flushw");
157 rw = (struct reg_window __user *)
158 (regs->u_regs[14] + STACK_BIAS);
159 rwk = (struct reg_window *)
160 (regs->u_regs[14] + STACK_BIAS);
161 if (!(regs->tstate & TSTATE_PRIV)) {
164 if (copy_from_user (&r_w, rw, sizeof(r_w))) {
172 show_regwindow32(regs);
175 printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
176 rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
177 printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
178 rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
179 printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
180 rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
181 printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
182 rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
183 if (regs->tstate & TSTATE_PRIV)
184 printk("I7: <%pS>\n", (void *) rwk->ins[7]);
187 void show_regs(struct pt_regs *regs)
189 printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x %s\n", regs->tstate,
190 regs->tpc, regs->tnpc, regs->y, print_tainted());
191 printk("TPC: <%pS>\n", (void *) regs->tpc);
192 printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
193 regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
195 printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
196 regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
198 printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
199 regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
201 printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
202 regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
204 printk("RPC: <%pS>\n", (void *) regs->u_regs[15]);
205 show_regwindow(regs);
206 show_stack(current, (unsigned long *) regs->u_regs[UREG_FP]);
209 union global_cpu_snapshot global_cpu_snapshot[NR_CPUS];
210 static DEFINE_SPINLOCK(global_cpu_snapshot_lock);
212 static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
215 struct global_reg_snapshot *rp;
219 rp = &global_cpu_snapshot[this_cpu].reg;
221 rp->tstate = regs->tstate;
223 rp->tnpc = regs->tnpc;
224 rp->o7 = regs->u_regs[UREG_I7];
226 if (regs->tstate & TSTATE_PRIV) {
227 struct reg_window *rw;
229 rw = (struct reg_window *)
230 (regs->u_regs[UREG_FP] + STACK_BIAS);
231 if (kstack_valid(tp, (unsigned long) rw)) {
233 rw = (struct reg_window *)
234 (rw->ins[6] + STACK_BIAS);
235 if (kstack_valid(tp, (unsigned long) rw))
236 rp->rpc = rw->ins[7];
245 /* In order to avoid hangs we do not try to synchronize with the
246 * global register dump client cpus. The last store they make is to
247 * the thread pointer, so do a short poll waiting for that to become
250 static void __global_reg_poll(struct global_reg_snapshot *gp)
254 while (!gp->thread && ++limit < 100) {
260 void arch_trigger_all_cpu_backtrace(void)
262 struct thread_info *tp = current_thread_info();
263 struct pt_regs *regs = get_irq_regs();
270 spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
272 memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
274 this_cpu = raw_smp_processor_id();
276 __global_reg_self(tp, regs, this_cpu);
278 smp_fetch_global_regs();
280 for_each_online_cpu(cpu) {
281 struct global_reg_snapshot *gp = &global_cpu_snapshot[cpu].reg;
283 __global_reg_poll(gp);
286 printk("%c CPU[%3d]: TSTATE[%016lx] TPC[%016lx] TNPC[%016lx] TASK[%s:%d]\n",
287 (cpu == this_cpu ? '*' : ' '), cpu,
288 gp->tstate, gp->tpc, gp->tnpc,
289 ((tp && tp->task) ? tp->task->comm : "NULL"),
290 ((tp && tp->task) ? tp->task->pid : -1));
292 if (gp->tstate & TSTATE_PRIV) {
293 printk(" TPC[%pS] O7[%pS] I7[%pS] RPC[%pS]\n",
299 printk(" TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
300 gp->tpc, gp->o7, gp->i7, gp->rpc);
304 memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
306 spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
309 #ifdef CONFIG_MAGIC_SYSRQ
311 static void sysrq_handle_globreg(int key)
313 arch_trigger_all_cpu_backtrace();
316 static struct sysrq_key_op sparc_globalreg_op = {
317 .handler = sysrq_handle_globreg,
318 .help_msg = "global-regs(Y)",
319 .action_msg = "Show Global CPU Regs",
322 static void __global_pmu_self(int this_cpu)
324 struct global_pmu_snapshot *pp;
327 pp = &global_cpu_snapshot[this_cpu].pmu;
330 if (tlb_type == hypervisor &&
331 sun4v_chip_type >= SUN4V_CHIP_NIAGARA4)
334 for (i = 0; i < num; i++) {
335 pp->pcr[i] = pcr_ops->read_pcr(i);
336 pp->pic[i] = pcr_ops->read_pic(i);
340 static void __global_pmu_poll(struct global_pmu_snapshot *pp)
344 while (!pp->pcr[0] && ++limit < 100) {
350 static void pmu_snapshot_all_cpus(void)
355 spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
357 memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
359 this_cpu = raw_smp_processor_id();
361 __global_pmu_self(this_cpu);
363 smp_fetch_global_pmu();
365 for_each_online_cpu(cpu) {
366 struct global_pmu_snapshot *pp = &global_cpu_snapshot[cpu].pmu;
368 __global_pmu_poll(pp);
370 printk("%c CPU[%3d]: PCR[%08lx:%08lx:%08lx:%08lx] PIC[%08lx:%08lx:%08lx:%08lx]\n",
371 (cpu == this_cpu ? '*' : ' '), cpu,
372 pp->pcr[0], pp->pcr[1], pp->pcr[2], pp->pcr[3],
373 pp->pic[0], pp->pic[1], pp->pic[2], pp->pic[3]);
376 memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
378 spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
381 static void sysrq_handle_globpmu(int key)
383 pmu_snapshot_all_cpus();
386 static struct sysrq_key_op sparc_globalpmu_op = {
387 .handler = sysrq_handle_globpmu,
388 .help_msg = "global-pmu(X)",
389 .action_msg = "Show Global PMU Regs",
392 static int __init sparc_sysrq_init(void)
394 int ret = register_sysrq_key('y', &sparc_globalreg_op);
397 ret = register_sysrq_key('x', &sparc_globalpmu_op);
401 core_initcall(sparc_sysrq_init);
405 unsigned long thread_saved_pc(struct task_struct *tsk)
407 struct thread_info *ti = task_thread_info(tsk);
408 unsigned long ret = 0xdeadbeefUL;
412 sp = (unsigned long *)(ti->ksp + STACK_BIAS);
413 if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
416 fp = (unsigned long *)(sp[14] + STACK_BIAS);
417 if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
424 /* Free current thread data structures etc.. */
425 void exit_thread(void)
427 struct thread_info *t = current_thread_info();
430 if (t->utraps[0] < 2)
437 void flush_thread(void)
439 struct thread_info *t = current_thread_info();
440 struct mm_struct *mm;
444 tsb_context_switch(mm);
446 set_thread_wsaved(0);
448 /* Clear FPU register state. */
452 /* It's a bit more tricky when 64-bit tasks are involved... */
453 static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
455 unsigned long fp, distance, rval;
457 if (!(test_thread_flag(TIF_32BIT))) {
460 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
463 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
465 /* Now align the stack as this is mandatory in the Sparc ABI
466 * due to how register windows work. This hides the
467 * restriction from thread libraries etc.
472 rval = (csp - distance);
473 if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
475 else if (test_thread_flag(TIF_32BIT)) {
476 if (put_user(((u32)csp),
477 &(((struct reg_window32 __user *)rval)->ins[6])))
480 if (put_user(((u64)csp - STACK_BIAS),
481 &(((struct reg_window __user *)rval)->ins[6])))
484 rval = rval - STACK_BIAS;
490 /* Standard stuff. */
491 static inline void shift_window_buffer(int first_win, int last_win,
492 struct thread_info *t)
496 for (i = first_win; i < last_win; i++) {
497 t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
498 memcpy(&t->reg_window[i], &t->reg_window[i+1],
499 sizeof(struct reg_window));
503 void synchronize_user_stack(void)
505 struct thread_info *t = current_thread_info();
506 unsigned long window;
508 flush_user_windows();
509 if ((window = get_thread_wsaved()) != 0) {
510 int winsize = sizeof(struct reg_window);
513 if (test_thread_flag(TIF_32BIT))
514 winsize = sizeof(struct reg_window32);
520 unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
521 struct reg_window *rwin = &t->reg_window[window];
523 if (!copy_to_user((char __user *)sp, rwin, winsize)) {
524 shift_window_buffer(window, get_thread_wsaved() - 1, t);
525 set_thread_wsaved(get_thread_wsaved() - 1);
531 static void stack_unaligned(unsigned long sp)
535 info.si_signo = SIGBUS;
537 info.si_code = BUS_ADRALN;
538 info.si_addr = (void __user *) sp;
540 force_sig_info(SIGBUS, &info, current);
543 void fault_in_user_windows(void)
545 struct thread_info *t = current_thread_info();
546 unsigned long window;
547 int winsize = sizeof(struct reg_window);
550 if (test_thread_flag(TIF_32BIT))
551 winsize = sizeof(struct reg_window32);
555 flush_user_windows();
556 window = get_thread_wsaved();
558 if (likely(window != 0)) {
561 unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
562 struct reg_window *rwin = &t->reg_window[window];
564 if (unlikely(sp & 0x7UL))
567 if (unlikely(copy_to_user((char __user *)sp,
572 set_thread_wsaved(0);
576 set_thread_wsaved(window + 1);
580 asmlinkage long sparc_do_fork(unsigned long clone_flags,
581 unsigned long stack_start,
582 struct pt_regs *regs,
583 unsigned long stack_size)
585 int __user *parent_tid_ptr, *child_tid_ptr;
586 unsigned long orig_i1 = regs->u_regs[UREG_I1];
590 if (test_thread_flag(TIF_32BIT)) {
591 parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
592 child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
596 parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
597 child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
600 ret = do_fork(clone_flags, stack_start,
602 parent_tid_ptr, child_tid_ptr);
604 /* If we get an error and potentially restart the system
605 * call, we're screwed because copy_thread() clobbered
606 * the parent's %o1. So detect that case and restore it
609 if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
610 regs->u_regs[UREG_I1] = orig_i1;
615 /* Copy a Sparc thread. The fork() return value conventions
616 * under SunOS are nothing short of bletcherous:
617 * Parent --> %o0 == childs pid, %o1 == 0
618 * Child --> %o0 == parents pid, %o1 == 1
620 int copy_thread(unsigned long clone_flags, unsigned long sp,
621 unsigned long unused,
622 struct task_struct *p, struct pt_regs *regs)
624 struct thread_info *t = task_thread_info(p);
625 struct sparc_stackf *parent_sf;
626 unsigned long child_stack_sz;
627 char *child_trap_frame;
630 kernel_thread = (regs->tstate & TSTATE_PRIV) ? 1 : 0;
631 parent_sf = ((struct sparc_stackf *) regs) - 1;
633 /* Calculate offset to stack_frame & pt_regs */
634 child_stack_sz = ((STACKFRAME_SZ + TRACEREG_SZ) +
635 (kernel_thread ? STACKFRAME_SZ : 0));
636 child_trap_frame = (task_stack_page(p) +
637 (THREAD_SIZE - child_stack_sz));
638 memcpy(child_trap_frame, parent_sf, child_stack_sz);
640 t->flags = (t->flags & ~((0xffUL << TI_FLAG_CWP_SHIFT) |
641 (0xffUL << TI_FLAG_CURRENT_DS_SHIFT))) |
642 (((regs->tstate + 1) & TSTATE_CWP) << TI_FLAG_CWP_SHIFT);
644 t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
645 t->kregs = (struct pt_regs *) (child_trap_frame +
646 sizeof(struct sparc_stackf));
650 struct sparc_stackf *child_sf = (struct sparc_stackf *)
651 (child_trap_frame + (STACKFRAME_SZ + TRACEREG_SZ));
653 /* Zero terminate the stack backtrace. */
655 t->kregs->u_regs[UREG_FP] =
656 ((unsigned long) child_sf) - STACK_BIAS;
658 t->flags |= ((long)ASI_P << TI_FLAG_CURRENT_DS_SHIFT);
659 t->kregs->u_regs[UREG_G6] = (unsigned long) t;
660 t->kregs->u_regs[UREG_G4] = (unsigned long) t->task;
662 if (t->flags & _TIF_32BIT) {
663 sp &= 0x00000000ffffffffUL;
664 regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
666 t->kregs->u_regs[UREG_FP] = sp;
667 t->flags |= ((long)ASI_AIUS << TI_FLAG_CURRENT_DS_SHIFT);
668 if (sp != regs->u_regs[UREG_FP]) {
671 csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
674 t->kregs->u_regs[UREG_FP] = csp;
680 /* Set the return value for the child. */
681 t->kregs->u_regs[UREG_I0] = current->pid;
682 t->kregs->u_regs[UREG_I1] = 1;
684 /* Set the second return value for the parent. */
685 regs->u_regs[UREG_I1] = 0;
687 if (clone_flags & CLONE_SETTLS)
688 t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
694 * This is the mechanism for creating a new kernel thread.
696 * NOTE! Only a kernel-only process(ie the swapper or direct descendants
697 * who haven't done an "execve()") should use this: it will work within
698 * a system call from a "real" process, but the process memory space will
699 * not be freed until both the parent and the child have exited.
701 pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
705 /* If the parent runs before fn(arg) is called by the child,
706 * the input registers of this function can be clobbered.
707 * So we stash 'fn' and 'arg' into global registers which
708 * will not be modified by the parent.
710 __asm__ __volatile__("mov %4, %%g2\n\t" /* Save FN into global */
711 "mov %5, %%g3\n\t" /* Save ARG into global */
712 "mov %1, %%g1\n\t" /* Clone syscall nr. */
713 "mov %2, %%o0\n\t" /* Clone flags. */
714 "mov 0, %%o1\n\t" /* usp arg == 0 */
715 "t 0x6d\n\t" /* Linux/Sparc clone(). */
716 "brz,a,pn %%o1, 1f\n\t" /* Parent, just return. */
718 "jmpl %%g2, %%o7\n\t" /* Call the function. */
719 " mov %%g3, %%o0\n\t" /* Set arg in delay. */
721 "t 0x6d\n\t" /* Linux/Sparc exit(). */
722 /* Notreached by child. */
725 "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
726 "i" (__NR_exit), "r" (fn), "r" (arg) :
727 "g1", "g2", "g3", "o0", "o1", "memory", "cc");
730 EXPORT_SYMBOL(kernel_thread);
734 unsigned int pr_regs[32];
735 unsigned long pr_dregs[16];
737 unsigned int __unused;
739 unsigned char pr_qcnt;
740 unsigned char pr_q_entrysize;
742 unsigned int pr_q[64];
746 * fill in the fpu structure for a core dump.
748 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
750 unsigned long *kfpregs = current_thread_info()->fpregs;
751 unsigned long fprs = current_thread_info()->fpsaved[0];
753 if (test_thread_flag(TIF_32BIT)) {
754 elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
757 memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
758 sizeof(unsigned int) * 32);
760 memset(&fpregs32->pr_fr.pr_regs[0], 0,
761 sizeof(unsigned int) * 32);
762 fpregs32->pr_qcnt = 0;
763 fpregs32->pr_q_entrysize = 8;
764 memset(&fpregs32->pr_q[0], 0,
765 (sizeof(unsigned int) * 64));
766 if (fprs & FPRS_FEF) {
767 fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
770 fpregs32->pr_fsr = 0;
775 memcpy(&fpregs->pr_regs[0], kfpregs,
776 sizeof(unsigned int) * 32);
778 memset(&fpregs->pr_regs[0], 0,
779 sizeof(unsigned int) * 32);
781 memcpy(&fpregs->pr_regs[16], kfpregs+16,
782 sizeof(unsigned int) * 32);
784 memset(&fpregs->pr_regs[16], 0,
785 sizeof(unsigned int) * 32);
786 if(fprs & FPRS_FEF) {
787 fpregs->pr_fsr = current_thread_info()->xfsr[0];
788 fpregs->pr_gsr = current_thread_info()->gsr[0];
790 fpregs->pr_fsr = fpregs->pr_gsr = 0;
792 fpregs->pr_fprs = fprs;
796 EXPORT_SYMBOL(dump_fpu);
799 * sparc_execve() executes a new program after the asm stub has set
800 * things up for us. This should basically do what I want it to.
802 asmlinkage int sparc_execve(struct pt_regs *regs)
805 struct filename *filename;
807 /* User register window flush is done by entry.S */
809 /* Check for indirect call. */
810 if (regs->u_regs[UREG_G1] == 0)
813 filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
814 error = PTR_ERR(filename);
815 if (IS_ERR(filename))
817 error = do_execve(filename->name,
818 (const char __user *const __user *)
819 regs->u_regs[base + UREG_I1],
820 (const char __user *const __user *)
821 regs->u_regs[base + UREG_I2], regs);
825 current_thread_info()->xfsr[0] = 0;
826 current_thread_info()->fpsaved[0] = 0;
827 regs->tstate &= ~TSTATE_PEF;
833 unsigned long get_wchan(struct task_struct *task)
835 unsigned long pc, fp, bias = 0;
836 struct thread_info *tp;
837 struct reg_window *rw;
838 unsigned long ret = 0;
841 if (!task || task == current ||
842 task->state == TASK_RUNNING)
845 tp = task_thread_info(task);
847 fp = task_thread_info(task)->ksp + bias;
850 if (!kstack_valid(tp, fp))
852 rw = (struct reg_window *) fp;
854 if (!in_sched_functions(pc)) {
858 fp = rw->ins[6] + bias;
859 } while (++count < 16);