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/module.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/reboot.h>
26 #include <linux/delay.h>
27 #include <linux/compat.h>
28 #include <linux/tick.h>
29 #include <linux/init.h>
30 #include <linux/cpu.h>
31 #include <linux/elfcore.h>
32 #include <linux/sysrq.h>
34 #include <asm/oplib.h>
35 #include <asm/uaccess.h>
36 #include <asm/system.h>
38 #include <asm/pgalloc.h>
39 #include <asm/pgtable.h>
40 #include <asm/processor.h>
41 #include <asm/pstate.h>
43 #include <asm/fpumacro.h>
45 #include <asm/cpudata.h>
46 #include <asm/mmu_context.h>
47 #include <asm/unistd.h>
48 #include <asm/hypervisor.h>
49 #include <asm/sstate.h>
50 #include <asm/reboot.h>
51 #include <asm/syscalls.h>
52 #include <asm/irq_regs.h>
55 static void sparc64_yield(int cpu)
57 if (tlb_type != hypervisor)
60 clear_thread_flag(TIF_POLLING_NRFLAG);
61 smp_mb__after_clear_bit();
63 while (!need_resched() && !cpu_is_offline(cpu)) {
66 /* Disable interrupts. */
68 "rdpr %%pstate, %0\n\t"
70 "wrpr %0, %%g0, %%pstate"
74 if (!need_resched() && !cpu_is_offline(cpu))
77 /* Re-enable interrupts. */
79 "rdpr %%pstate, %0\n\t"
81 "wrpr %0, %%g0, %%pstate"
86 set_thread_flag(TIF_POLLING_NRFLAG);
89 /* The idle loop on sparc64. */
92 int cpu = smp_processor_id();
94 set_thread_flag(TIF_POLLING_NRFLAG);
97 tick_nohz_stop_sched_tick(1);
99 while (!need_resched() && !cpu_is_offline(cpu))
102 tick_nohz_restart_sched_tick();
104 preempt_enable_no_resched();
106 #ifdef CONFIG_HOTPLUG_CPU
107 if (cpu_is_offline(cpu))
116 void machine_halt(void)
120 panic("Halt failed!");
123 void machine_alt_power_off(void)
126 prom_halt_power_off();
127 panic("Power-off failed!");
130 void machine_restart(char * cmd)
135 p = strchr (reboot_command, '\n');
140 prom_reboot(reboot_command);
142 panic("Reboot failed!");
146 static void show_regwindow32(struct pt_regs *regs)
148 struct reg_window32 __user *rw;
149 struct reg_window32 r_w;
152 __asm__ __volatile__ ("flushw");
153 rw = compat_ptr((unsigned)regs->u_regs[14]);
156 if (copy_from_user (&r_w, rw, sizeof(r_w))) {
162 printk("l0: %08x l1: %08x l2: %08x l3: %08x "
163 "l4: %08x l5: %08x l6: %08x l7: %08x\n",
164 r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
165 r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
166 printk("i0: %08x i1: %08x i2: %08x i3: %08x "
167 "i4: %08x i5: %08x i6: %08x i7: %08x\n",
168 r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
169 r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
172 #define show_regwindow32(regs) do { } while (0)
175 static void show_regwindow(struct pt_regs *regs)
177 struct reg_window __user *rw;
178 struct reg_window *rwk;
179 struct reg_window r_w;
182 if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
183 __asm__ __volatile__ ("flushw");
184 rw = (struct reg_window __user *)
185 (regs->u_regs[14] + STACK_BIAS);
186 rwk = (struct reg_window *)
187 (regs->u_regs[14] + STACK_BIAS);
188 if (!(regs->tstate & TSTATE_PRIV)) {
191 if (copy_from_user (&r_w, rw, sizeof(r_w))) {
199 show_regwindow32(regs);
202 printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
203 rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
204 printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
205 rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
206 printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
207 rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
208 printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
209 rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
210 if (regs->tstate & TSTATE_PRIV)
211 printk("I7: <%pS>\n", (void *) rwk->ins[7]);
215 static DEFINE_SPINLOCK(regdump_lock);
218 void __show_regs(struct pt_regs * regs)
223 /* Protect against xcall ipis which might lead to livelock on the lock */
224 __asm__ __volatile__("rdpr %%pstate, %0\n\t"
225 "wrpr %0, %1, %%pstate"
228 spin_lock(®dump_lock);
230 printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x %s\n", regs->tstate,
231 regs->tpc, regs->tnpc, regs->y, print_tainted());
232 printk("TPC: <%pS>\n", (void *) regs->tpc);
233 printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
234 regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
236 printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
237 regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
239 printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
240 regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
242 printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
243 regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
245 printk("RPC: <%pS>\n", (void *) regs->u_regs[15]);
246 show_regwindow(regs);
248 spin_unlock(®dump_lock);
249 __asm__ __volatile__("wrpr %0, 0, %%pstate"
254 void show_regs(struct pt_regs *regs)
260 extern void smp_report_regs(void);
268 struct global_reg_snapshot global_reg_snapshot[NR_CPUS];
269 static DEFINE_SPINLOCK(global_reg_snapshot_lock);
271 static bool kstack_valid(struct thread_info *tp, struct reg_window *rw)
273 unsigned long thread_base, fp;
275 thread_base = (unsigned long) tp;
276 fp = (unsigned long) rw;
278 if (fp < (thread_base + sizeof(struct thread_info)) ||
279 fp >= (thread_base + THREAD_SIZE))
284 static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
289 global_reg_snapshot[this_cpu].tstate = regs->tstate;
290 global_reg_snapshot[this_cpu].tpc = regs->tpc;
291 global_reg_snapshot[this_cpu].tnpc = regs->tnpc;
292 global_reg_snapshot[this_cpu].o7 = regs->u_regs[UREG_I7];
294 if (regs->tstate & TSTATE_PRIV) {
295 struct thread_info *tp = current_thread_info();
296 struct reg_window *rw;
298 rw = (struct reg_window *)
299 (regs->u_regs[UREG_FP] + STACK_BIAS);
300 if (kstack_valid(tp, rw)) {
301 global_reg_snapshot[this_cpu].i7 = rw->ins[7];
302 rw = (struct reg_window *)
303 (rw->ins[6] + STACK_BIAS);
304 if (kstack_valid(tp, rw))
305 global_reg_snapshot[this_cpu].rpc = rw->ins[7];
308 global_reg_snapshot[this_cpu].i7 = 0;
309 global_reg_snapshot[this_cpu].rpc = 0;
311 global_reg_snapshot[this_cpu].thread = tp;
314 /* In order to avoid hangs we do not try to synchronize with the
315 * global register dump client cpus. The last store they make is to
316 * the thread pointer, so do a short poll waiting for that to become
319 static void __global_reg_poll(struct global_reg_snapshot *gp)
323 while (!gp->thread && ++limit < 100) {
329 void __trigger_all_cpu_backtrace(void)
331 struct thread_info *tp = current_thread_info();
332 struct pt_regs *regs = get_irq_regs();
339 spin_lock_irqsave(&global_reg_snapshot_lock, flags);
341 memset(global_reg_snapshot, 0, sizeof(global_reg_snapshot));
343 this_cpu = raw_smp_processor_id();
345 __global_reg_self(tp, regs, this_cpu);
347 smp_fetch_global_regs();
349 for_each_online_cpu(cpu) {
350 struct global_reg_snapshot *gp = &global_reg_snapshot[cpu];
351 struct thread_info *tp;
353 __global_reg_poll(gp);
356 printk("%c CPU[%3d]: TSTATE[%016lx] TPC[%016lx] TNPC[%016lx] TASK[%s:%d]\n",
357 (cpu == this_cpu ? '*' : ' '), cpu,
358 gp->tstate, gp->tpc, gp->tnpc,
359 ((tp && tp->task) ? tp->task->comm : "NULL"),
360 ((tp && tp->task) ? tp->task->pid : -1));
362 if (gp->tstate & TSTATE_PRIV) {
363 printk(" TPC[%pS] O7[%pS] I7[%pS] RPC[%pS]\n",
369 printk(" TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
370 gp->tpc, gp->o7, gp->i7, gp->rpc);
374 memset(global_reg_snapshot, 0, sizeof(global_reg_snapshot));
376 spin_unlock_irqrestore(&global_reg_snapshot_lock, flags);
379 #ifdef CONFIG_MAGIC_SYSRQ
381 static void sysrq_handle_globreg(int key, struct tty_struct *tty)
383 __trigger_all_cpu_backtrace();
386 static struct sysrq_key_op sparc_globalreg_op = {
387 .handler = sysrq_handle_globreg,
388 .help_msg = "Globalregs",
389 .action_msg = "Show Global CPU Regs",
392 static int __init sparc_globreg_init(void)
394 return register_sysrq_key('y', &sparc_globalreg_op);
397 core_initcall(sparc_globreg_init);
401 unsigned long thread_saved_pc(struct task_struct *tsk)
403 struct thread_info *ti = task_thread_info(tsk);
404 unsigned long ret = 0xdeadbeefUL;
408 sp = (unsigned long *)(ti->ksp + STACK_BIAS);
409 if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
412 fp = (unsigned long *)(sp[14] + STACK_BIAS);
413 if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
420 /* Free current thread data structures etc.. */
421 void exit_thread(void)
423 struct thread_info *t = current_thread_info();
426 if (t->utraps[0] < 2)
432 if (test_and_clear_thread_flag(TIF_PERFCTR)) {
433 t->user_cntd0 = t->user_cntd1 = NULL;
439 void flush_thread(void)
441 struct thread_info *t = current_thread_info();
442 struct mm_struct *mm;
444 if (test_ti_thread_flag(t, TIF_ABI_PENDING)) {
445 clear_ti_thread_flag(t, TIF_ABI_PENDING);
446 if (test_ti_thread_flag(t, TIF_32BIT))
447 clear_ti_thread_flag(t, TIF_32BIT);
449 set_ti_thread_flag(t, TIF_32BIT);
454 tsb_context_switch(mm);
456 set_thread_wsaved(0);
458 /* Turn off performance counters if on. */
459 if (test_and_clear_thread_flag(TIF_PERFCTR)) {
460 t->user_cntd0 = t->user_cntd1 = NULL;
465 /* Clear FPU register state. */
468 if (get_thread_current_ds() != ASI_AIUS)
472 /* It's a bit more tricky when 64-bit tasks are involved... */
473 static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
475 unsigned long fp, distance, rval;
477 if (!(test_thread_flag(TIF_32BIT))) {
480 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
483 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
485 /* Now 8-byte align the stack as this is mandatory in the
486 * Sparc ABI due to how register windows work. This hides
487 * the restriction from thread libraries etc. -DaveM
492 rval = (csp - distance);
493 if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
495 else if (test_thread_flag(TIF_32BIT)) {
496 if (put_user(((u32)csp),
497 &(((struct reg_window32 __user *)rval)->ins[6])))
500 if (put_user(((u64)csp - STACK_BIAS),
501 &(((struct reg_window __user *)rval)->ins[6])))
504 rval = rval - STACK_BIAS;
510 /* Standard stuff. */
511 static inline void shift_window_buffer(int first_win, int last_win,
512 struct thread_info *t)
516 for (i = first_win; i < last_win; i++) {
517 t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
518 memcpy(&t->reg_window[i], &t->reg_window[i+1],
519 sizeof(struct reg_window));
523 void synchronize_user_stack(void)
525 struct thread_info *t = current_thread_info();
526 unsigned long window;
528 flush_user_windows();
529 if ((window = get_thread_wsaved()) != 0) {
530 int winsize = sizeof(struct reg_window);
533 if (test_thread_flag(TIF_32BIT))
534 winsize = sizeof(struct reg_window32);
540 unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
541 struct reg_window *rwin = &t->reg_window[window];
543 if (!copy_to_user((char __user *)sp, rwin, winsize)) {
544 shift_window_buffer(window, get_thread_wsaved() - 1, t);
545 set_thread_wsaved(get_thread_wsaved() - 1);
551 static void stack_unaligned(unsigned long sp)
555 info.si_signo = SIGBUS;
557 info.si_code = BUS_ADRALN;
558 info.si_addr = (void __user *) sp;
560 force_sig_info(SIGBUS, &info, current);
563 void fault_in_user_windows(void)
565 struct thread_info *t = current_thread_info();
566 unsigned long window;
567 int winsize = sizeof(struct reg_window);
570 if (test_thread_flag(TIF_32BIT))
571 winsize = sizeof(struct reg_window32);
575 flush_user_windows();
576 window = get_thread_wsaved();
578 if (likely(window != 0)) {
581 unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
582 struct reg_window *rwin = &t->reg_window[window];
584 if (unlikely(sp & 0x7UL))
587 if (unlikely(copy_to_user((char __user *)sp,
592 set_thread_wsaved(0);
596 set_thread_wsaved(window + 1);
600 asmlinkage long sparc_do_fork(unsigned long clone_flags,
601 unsigned long stack_start,
602 struct pt_regs *regs,
603 unsigned long stack_size)
605 int __user *parent_tid_ptr, *child_tid_ptr;
606 unsigned long orig_i1 = regs->u_regs[UREG_I1];
610 if (test_thread_flag(TIF_32BIT)) {
611 parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
612 child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
616 parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
617 child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
620 ret = do_fork(clone_flags, stack_start,
622 parent_tid_ptr, child_tid_ptr);
624 /* If we get an error and potentially restart the system
625 * call, we're screwed because copy_thread() clobbered
626 * the parent's %o1. So detect that case and restore it
629 if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
630 regs->u_regs[UREG_I1] = orig_i1;
635 /* Copy a Sparc thread. The fork() return value conventions
636 * under SunOS are nothing short of bletcherous:
637 * Parent --> %o0 == childs pid, %o1 == 0
638 * Child --> %o0 == parents pid, %o1 == 1
640 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
641 unsigned long unused,
642 struct task_struct *p, struct pt_regs *regs)
644 struct thread_info *t = task_thread_info(p);
645 struct sparc_stackf *parent_sf;
646 unsigned long child_stack_sz;
647 char *child_trap_frame;
650 kernel_thread = (regs->tstate & TSTATE_PRIV) ? 1 : 0;
651 parent_sf = ((struct sparc_stackf *) regs) - 1;
653 /* Calculate offset to stack_frame & pt_regs */
654 child_stack_sz = ((STACKFRAME_SZ + TRACEREG_SZ) +
655 (kernel_thread ? STACKFRAME_SZ : 0));
656 child_trap_frame = (task_stack_page(p) +
657 (THREAD_SIZE - child_stack_sz));
658 memcpy(child_trap_frame, parent_sf, child_stack_sz);
660 t->flags = (t->flags & ~((0xffUL << TI_FLAG_CWP_SHIFT) |
661 (0xffUL << TI_FLAG_CURRENT_DS_SHIFT))) |
662 (((regs->tstate + 1) & TSTATE_CWP) << TI_FLAG_CWP_SHIFT);
664 t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
665 t->kregs = (struct pt_regs *) (child_trap_frame +
666 sizeof(struct sparc_stackf));
670 struct sparc_stackf *child_sf = (struct sparc_stackf *)
671 (child_trap_frame + (STACKFRAME_SZ + TRACEREG_SZ));
673 /* Zero terminate the stack backtrace. */
675 t->kregs->u_regs[UREG_FP] =
676 ((unsigned long) child_sf) - STACK_BIAS;
678 /* Special case, if we are spawning a kernel thread from
679 * a userspace task (usermode helper, NFS or similar), we
680 * must disable performance counters in the child because
681 * the address space and protection realm are changing.
683 if (t->flags & _TIF_PERFCTR) {
684 t->user_cntd0 = t->user_cntd1 = NULL;
686 t->flags &= ~_TIF_PERFCTR;
688 t->flags |= ((long)ASI_P << TI_FLAG_CURRENT_DS_SHIFT);
689 t->kregs->u_regs[UREG_G6] = (unsigned long) t;
690 t->kregs->u_regs[UREG_G4] = (unsigned long) t->task;
692 if (t->flags & _TIF_32BIT) {
693 sp &= 0x00000000ffffffffUL;
694 regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
696 t->kregs->u_regs[UREG_FP] = sp;
697 t->flags |= ((long)ASI_AIUS << TI_FLAG_CURRENT_DS_SHIFT);
698 if (sp != regs->u_regs[UREG_FP]) {
701 csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
704 t->kregs->u_regs[UREG_FP] = csp;
710 /* Set the return value for the child. */
711 t->kregs->u_regs[UREG_I0] = current->pid;
712 t->kregs->u_regs[UREG_I1] = 1;
714 /* Set the second return value for the parent. */
715 regs->u_regs[UREG_I1] = 0;
717 if (clone_flags & CLONE_SETTLS)
718 t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
724 * This is the mechanism for creating a new kernel thread.
726 * NOTE! Only a kernel-only process(ie the swapper or direct descendants
727 * who haven't done an "execve()") should use this: it will work within
728 * a system call from a "real" process, but the process memory space will
729 * not be freed until both the parent and the child have exited.
731 pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
735 /* If the parent runs before fn(arg) is called by the child,
736 * the input registers of this function can be clobbered.
737 * So we stash 'fn' and 'arg' into global registers which
738 * will not be modified by the parent.
740 __asm__ __volatile__("mov %4, %%g2\n\t" /* Save FN into global */
741 "mov %5, %%g3\n\t" /* Save ARG into global */
742 "mov %1, %%g1\n\t" /* Clone syscall nr. */
743 "mov %2, %%o0\n\t" /* Clone flags. */
744 "mov 0, %%o1\n\t" /* usp arg == 0 */
745 "t 0x6d\n\t" /* Linux/Sparc clone(). */
746 "brz,a,pn %%o1, 1f\n\t" /* Parent, just return. */
748 "jmpl %%g2, %%o7\n\t" /* Call the function. */
749 " mov %%g3, %%o0\n\t" /* Set arg in delay. */
751 "t 0x6d\n\t" /* Linux/Sparc exit(). */
752 /* Notreached by child. */
755 "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
756 "i" (__NR_exit), "r" (fn), "r" (arg) :
757 "g1", "g2", "g3", "o0", "o1", "memory", "cc");
763 unsigned int pr_regs[32];
764 unsigned long pr_dregs[16];
766 unsigned int __unused;
768 unsigned char pr_qcnt;
769 unsigned char pr_q_entrysize;
771 unsigned int pr_q[64];
775 * fill in the fpu structure for a core dump.
777 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
779 unsigned long *kfpregs = current_thread_info()->fpregs;
780 unsigned long fprs = current_thread_info()->fpsaved[0];
782 if (test_thread_flag(TIF_32BIT)) {
783 elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
786 memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
787 sizeof(unsigned int) * 32);
789 memset(&fpregs32->pr_fr.pr_regs[0], 0,
790 sizeof(unsigned int) * 32);
791 fpregs32->pr_qcnt = 0;
792 fpregs32->pr_q_entrysize = 8;
793 memset(&fpregs32->pr_q[0], 0,
794 (sizeof(unsigned int) * 64));
795 if (fprs & FPRS_FEF) {
796 fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
799 fpregs32->pr_fsr = 0;
804 memcpy(&fpregs->pr_regs[0], kfpregs,
805 sizeof(unsigned int) * 32);
807 memset(&fpregs->pr_regs[0], 0,
808 sizeof(unsigned int) * 32);
810 memcpy(&fpregs->pr_regs[16], kfpregs+16,
811 sizeof(unsigned int) * 32);
813 memset(&fpregs->pr_regs[16], 0,
814 sizeof(unsigned int) * 32);
815 if(fprs & FPRS_FEF) {
816 fpregs->pr_fsr = current_thread_info()->xfsr[0];
817 fpregs->pr_gsr = current_thread_info()->gsr[0];
819 fpregs->pr_fsr = fpregs->pr_gsr = 0;
821 fpregs->pr_fprs = fprs;
827 * sparc_execve() executes a new program after the asm stub has set
828 * things up for us. This should basically do what I want it to.
830 asmlinkage int sparc_execve(struct pt_regs *regs)
835 /* User register window flush is done by entry.S */
837 /* Check for indirect call. */
838 if (regs->u_regs[UREG_G1] == 0)
841 filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
842 error = PTR_ERR(filename);
843 if (IS_ERR(filename))
845 error = do_execve(filename,
846 (char __user * __user *)
847 regs->u_regs[base + UREG_I1],
848 (char __user * __user *)
849 regs->u_regs[base + UREG_I2], regs);
853 current_thread_info()->xfsr[0] = 0;
854 current_thread_info()->fpsaved[0] = 0;
855 regs->tstate &= ~TSTATE_PEF;
861 unsigned long get_wchan(struct task_struct *task)
863 unsigned long pc, fp, bias = 0;
864 unsigned long thread_info_base;
865 struct reg_window *rw;
866 unsigned long ret = 0;
869 if (!task || task == current ||
870 task->state == TASK_RUNNING)
873 thread_info_base = (unsigned long) task_stack_page(task);
875 fp = task_thread_info(task)->ksp + bias;
878 /* Bogus frame pointer? */
879 if (fp < (thread_info_base + sizeof(struct thread_info)) ||
880 fp >= (thread_info_base + THREAD_SIZE))
882 rw = (struct reg_window *) fp;
884 if (!in_sched_functions(pc)) {
888 fp = rw->ins[6] + bias;
889 } while (++count < 16);