| /* linux/arch/sparc/kernel/process.c |
| * |
| * Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net) |
| * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be) |
| */ |
| |
| /* |
| * This file handles the architecture-dependent parts of process handling.. |
| */ |
| |
| #include <stdarg.h> |
| |
| #include <linux/errno.h> |
| #include <linux/module.h> |
| #include <linux/sched.h> |
| #include <linux/kernel.h> |
| #include <linux/mm.h> |
| #include <linux/stddef.h> |
| #include <linux/ptrace.h> |
| #include <linux/user.h> |
| #include <linux/smp.h> |
| #include <linux/reboot.h> |
| #include <linux/delay.h> |
| #include <linux/pm.h> |
| #include <linux/init.h> |
| #include <linux/slab.h> |
| |
| #include <asm/auxio.h> |
| #include <asm/oplib.h> |
| #include <asm/uaccess.h> |
| #include <asm/system.h> |
| #include <asm/page.h> |
| #include <asm/pgalloc.h> |
| #include <asm/pgtable.h> |
| #include <asm/delay.h> |
| #include <asm/processor.h> |
| #include <asm/psr.h> |
| #include <asm/elf.h> |
| #include <asm/prom.h> |
| #include <asm/unistd.h> |
| |
| /* |
| * Power management idle function |
| * Set in pm platform drivers (apc.c and pmc.c) |
| */ |
| void (*pm_idle)(void); |
| EXPORT_SYMBOL(pm_idle); |
| |
| /* |
| * Power-off handler instantiation for pm.h compliance |
| * This is done via auxio, but could be used as a fallback |
| * handler when auxio is not present-- unused for now... |
| */ |
| void (*pm_power_off)(void) = machine_power_off; |
| EXPORT_SYMBOL(pm_power_off); |
| |
| /* |
| * sysctl - toggle power-off restriction for serial console |
| * systems in machine_power_off() |
| */ |
| int scons_pwroff = 1; |
| |
| extern void fpsave(unsigned long *, unsigned long *, void *, unsigned long *); |
| |
| struct task_struct *last_task_used_math = NULL; |
| struct thread_info *current_set[NR_CPUS]; |
| |
| #ifndef CONFIG_SMP |
| |
| #define SUN4C_FAULT_HIGH 100 |
| |
| /* |
| * the idle loop on a Sparc... ;) |
| */ |
| void cpu_idle(void) |
| { |
| /* endless idle loop with no priority at all */ |
| for (;;) { |
| if (ARCH_SUN4C) { |
| static int count = HZ; |
| static unsigned long last_jiffies; |
| static unsigned long last_faults; |
| static unsigned long fps; |
| unsigned long now; |
| unsigned long faults; |
| |
| extern unsigned long sun4c_kernel_faults; |
| extern void sun4c_grow_kernel_ring(void); |
| |
| local_irq_disable(); |
| now = jiffies; |
| count -= (now - last_jiffies); |
| last_jiffies = now; |
| if (count < 0) { |
| count += HZ; |
| faults = sun4c_kernel_faults; |
| fps = (fps + (faults - last_faults)) >> 1; |
| last_faults = faults; |
| #if 0 |
| printk("kernel faults / second = %ld\n", fps); |
| #endif |
| if (fps >= SUN4C_FAULT_HIGH) { |
| sun4c_grow_kernel_ring(); |
| } |
| } |
| local_irq_enable(); |
| } |
| |
| if (pm_idle) { |
| while (!need_resched()) |
| (*pm_idle)(); |
| } else { |
| while (!need_resched()) |
| cpu_relax(); |
| } |
| preempt_enable_no_resched(); |
| schedule(); |
| preempt_disable(); |
| check_pgt_cache(); |
| } |
| } |
| |
| #else |
| |
| /* This is being executed in task 0 'user space'. */ |
| void cpu_idle(void) |
| { |
| set_thread_flag(TIF_POLLING_NRFLAG); |
| /* endless idle loop with no priority at all */ |
| while(1) { |
| while (!need_resched()) |
| cpu_relax(); |
| preempt_enable_no_resched(); |
| schedule(); |
| preempt_disable(); |
| check_pgt_cache(); |
| } |
| } |
| |
| #endif |
| |
| /* XXX cli/sti -> local_irq_xxx here, check this works once SMP is fixed. */ |
| void machine_halt(void) |
| { |
| local_irq_enable(); |
| mdelay(8); |
| local_irq_disable(); |
| prom_halt(); |
| panic("Halt failed!"); |
| } |
| |
| void machine_restart(char * cmd) |
| { |
| char *p; |
| |
| local_irq_enable(); |
| mdelay(8); |
| local_irq_disable(); |
| |
| p = strchr (reboot_command, '\n'); |
| if (p) *p = 0; |
| if (cmd) |
| prom_reboot(cmd); |
| if (*reboot_command) |
| prom_reboot(reboot_command); |
| prom_feval ("reset"); |
| panic("Reboot failed!"); |
| } |
| |
| void machine_power_off(void) |
| { |
| if (auxio_power_register && |
| (strcmp(of_console_device->type, "serial") || scons_pwroff)) |
| *auxio_power_register |= AUXIO_POWER_OFF; |
| machine_halt(); |
| } |
| |
| #if 0 |
| |
| static DEFINE_SPINLOCK(sparc_backtrace_lock); |
| |
| void __show_backtrace(unsigned long fp) |
| { |
| struct reg_window32 *rw; |
| unsigned long flags; |
| int cpu = smp_processor_id(); |
| |
| spin_lock_irqsave(&sparc_backtrace_lock, flags); |
| |
| rw = (struct reg_window32 *)fp; |
| while(rw && (((unsigned long) rw) >= PAGE_OFFSET) && |
| !(((unsigned long) rw) & 0x7)) { |
| printk("CPU[%d]: ARGS[%08lx,%08lx,%08lx,%08lx,%08lx,%08lx] " |
| "FP[%08lx] CALLER[%08lx]: ", cpu, |
| rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3], |
| rw->ins[4], rw->ins[5], |
| rw->ins[6], |
| rw->ins[7]); |
| printk("%pS\n", (void *) rw->ins[7]); |
| rw = (struct reg_window32 *) rw->ins[6]; |
| } |
| spin_unlock_irqrestore(&sparc_backtrace_lock, flags); |
| } |
| |
| #define __SAVE __asm__ __volatile__("save %sp, -0x40, %sp\n\t") |
| #define __RESTORE __asm__ __volatile__("restore %g0, %g0, %g0\n\t") |
| #define __GET_FP(fp) __asm__ __volatile__("mov %%i6, %0" : "=r" (fp)) |
| |
| void show_backtrace(void) |
| { |
| unsigned long fp; |
| |
| __SAVE; __SAVE; __SAVE; __SAVE; |
| __SAVE; __SAVE; __SAVE; __SAVE; |
| __RESTORE; __RESTORE; __RESTORE; __RESTORE; |
| __RESTORE; __RESTORE; __RESTORE; __RESTORE; |
| |
| __GET_FP(fp); |
| |
| __show_backtrace(fp); |
| } |
| |
| #ifdef CONFIG_SMP |
| void smp_show_backtrace_all_cpus(void) |
| { |
| xc0((smpfunc_t) show_backtrace); |
| show_backtrace(); |
| } |
| #endif |
| |
| void show_stackframe(struct sparc_stackf *sf) |
| { |
| unsigned long size; |
| unsigned long *stk; |
| int i; |
| |
| printk("l0: %08lx l1: %08lx l2: %08lx l3: %08lx " |
| "l4: %08lx l5: %08lx l6: %08lx l7: %08lx\n", |
| sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3], |
| sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]); |
| printk("i0: %08lx i1: %08lx i2: %08lx i3: %08lx " |
| "i4: %08lx i5: %08lx fp: %08lx i7: %08lx\n", |
| sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3], |
| sf->ins[4], sf->ins[5], (unsigned long)sf->fp, sf->callers_pc); |
| printk("sp: %08lx x0: %08lx x1: %08lx x2: %08lx " |
| "x3: %08lx x4: %08lx x5: %08lx xx: %08lx\n", |
| (unsigned long)sf->structptr, sf->xargs[0], sf->xargs[1], |
| sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5], |
| sf->xxargs[0]); |
| size = ((unsigned long)sf->fp) - ((unsigned long)sf); |
| size -= STACKFRAME_SZ; |
| stk = (unsigned long *)((unsigned long)sf + STACKFRAME_SZ); |
| i = 0; |
| do { |
| printk("s%d: %08lx\n", i++, *stk++); |
| } while ((size -= sizeof(unsigned long))); |
| } |
| #endif |
| |
| void show_regs(struct pt_regs *r) |
| { |
| struct reg_window32 *rw = (struct reg_window32 *) r->u_regs[14]; |
| |
| printk("PSR: %08lx PC: %08lx NPC: %08lx Y: %08lx %s\n", |
| r->psr, r->pc, r->npc, r->y, print_tainted()); |
| printk("PC: <%pS>\n", (void *) r->pc); |
| printk("%%G: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n", |
| r->u_regs[0], r->u_regs[1], r->u_regs[2], r->u_regs[3], |
| r->u_regs[4], r->u_regs[5], r->u_regs[6], r->u_regs[7]); |
| printk("%%O: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n", |
| r->u_regs[8], r->u_regs[9], r->u_regs[10], r->u_regs[11], |
| r->u_regs[12], r->u_regs[13], r->u_regs[14], r->u_regs[15]); |
| printk("RPC: <%pS>\n", (void *) r->u_regs[15]); |
| |
| printk("%%L: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n", |
| rw->locals[0], rw->locals[1], rw->locals[2], rw->locals[3], |
| rw->locals[4], rw->locals[5], rw->locals[6], rw->locals[7]); |
| printk("%%I: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n", |
| rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3], |
| rw->ins[4], rw->ins[5], rw->ins[6], rw->ins[7]); |
| } |
| |
| /* |
| * The show_stack is an external API which we do not use ourselves. |
| * The oops is printed in die_if_kernel. |
| */ |
| void show_stack(struct task_struct *tsk, unsigned long *_ksp) |
| { |
| unsigned long pc, fp; |
| unsigned long task_base; |
| struct reg_window32 *rw; |
| int count = 0; |
| |
| if (tsk != NULL) |
| task_base = (unsigned long) task_stack_page(tsk); |
| else |
| task_base = (unsigned long) current_thread_info(); |
| |
| fp = (unsigned long) _ksp; |
| do { |
| /* Bogus frame pointer? */ |
| if (fp < (task_base + sizeof(struct thread_info)) || |
| fp >= (task_base + (PAGE_SIZE << 1))) |
| break; |
| rw = (struct reg_window32 *) fp; |
| pc = rw->ins[7]; |
| printk("[%08lx : ", pc); |
| printk("%pS ] ", (void *) pc); |
| fp = rw->ins[6]; |
| } while (++count < 16); |
| printk("\n"); |
| } |
| |
| void dump_stack(void) |
| { |
| unsigned long *ksp; |
| |
| __asm__ __volatile__("mov %%fp, %0" |
| : "=r" (ksp)); |
| show_stack(current, ksp); |
| } |
| |
| EXPORT_SYMBOL(dump_stack); |
| |
| /* |
| * Note: sparc64 has a pretty intricated thread_saved_pc, check it out. |
| */ |
| unsigned long thread_saved_pc(struct task_struct *tsk) |
| { |
| return task_thread_info(tsk)->kpc; |
| } |
| |
| /* |
| * Free current thread data structures etc.. |
| */ |
| void exit_thread(void) |
| { |
| #ifndef CONFIG_SMP |
| if(last_task_used_math == current) { |
| #else |
| if (test_thread_flag(TIF_USEDFPU)) { |
| #endif |
| /* Keep process from leaving FPU in a bogon state. */ |
| put_psr(get_psr() | PSR_EF); |
| fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr, |
| ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth); |
| #ifndef CONFIG_SMP |
| last_task_used_math = NULL; |
| #else |
| clear_thread_flag(TIF_USEDFPU); |
| #endif |
| } |
| } |
| |
| void flush_thread(void) |
| { |
| current_thread_info()->w_saved = 0; |
| |
| #ifndef CONFIG_SMP |
| if(last_task_used_math == current) { |
| #else |
| if (test_thread_flag(TIF_USEDFPU)) { |
| #endif |
| /* Clean the fpu. */ |
| put_psr(get_psr() | PSR_EF); |
| fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr, |
| ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth); |
| #ifndef CONFIG_SMP |
| last_task_used_math = NULL; |
| #else |
| clear_thread_flag(TIF_USEDFPU); |
| #endif |
| } |
| |
| /* Now, this task is no longer a kernel thread. */ |
| current->thread.current_ds = USER_DS; |
| if (current->thread.flags & SPARC_FLAG_KTHREAD) { |
| current->thread.flags &= ~SPARC_FLAG_KTHREAD; |
| |
| /* We must fixup kregs as well. */ |
| /* XXX This was not fixed for ti for a while, worked. Unused? */ |
| current->thread.kregs = (struct pt_regs *) |
| (task_stack_page(current) + (THREAD_SIZE - TRACEREG_SZ)); |
| } |
| } |
| |
| static inline struct sparc_stackf __user * |
| clone_stackframe(struct sparc_stackf __user *dst, |
| struct sparc_stackf __user *src) |
| { |
| unsigned long size, fp; |
| struct sparc_stackf *tmp; |
| struct sparc_stackf __user *sp; |
| |
| if (get_user(tmp, &src->fp)) |
| return NULL; |
| |
| fp = (unsigned long) tmp; |
| size = (fp - ((unsigned long) src)); |
| fp = (unsigned long) dst; |
| sp = (struct sparc_stackf __user *)(fp - size); |
| |
| /* do_fork() grabs the parent semaphore, we must release it |
| * temporarily so we can build the child clone stack frame |
| * without deadlocking. |
| */ |
| if (__copy_user(sp, src, size)) |
| sp = NULL; |
| else if (put_user(fp, &sp->fp)) |
| sp = NULL; |
| |
| return sp; |
| } |
| |
| asmlinkage int sparc_do_fork(unsigned long clone_flags, |
| unsigned long stack_start, |
| struct pt_regs *regs, |
| unsigned long stack_size) |
| { |
| unsigned long parent_tid_ptr, child_tid_ptr; |
| unsigned long orig_i1 = regs->u_regs[UREG_I1]; |
| long ret; |
| |
| parent_tid_ptr = regs->u_regs[UREG_I2]; |
| child_tid_ptr = regs->u_regs[UREG_I4]; |
| |
| ret = do_fork(clone_flags, stack_start, |
| regs, stack_size, |
| (int __user *) parent_tid_ptr, |
| (int __user *) child_tid_ptr); |
| |
| /* If we get an error and potentially restart the system |
| * call, we're screwed because copy_thread() clobbered |
| * the parent's %o1. So detect that case and restore it |
| * here. |
| */ |
| if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK) |
| regs->u_regs[UREG_I1] = orig_i1; |
| |
| return ret; |
| } |
| |
| /* Copy a Sparc thread. The fork() return value conventions |
| * under SunOS are nothing short of bletcherous: |
| * Parent --> %o0 == childs pid, %o1 == 0 |
| * Child --> %o0 == parents pid, %o1 == 1 |
| * |
| * NOTE: We have a separate fork kpsr/kwim because |
| * the parent could change these values between |
| * sys_fork invocation and when we reach here |
| * if the parent should sleep while trying to |
| * allocate the task_struct and kernel stack in |
| * do_fork(). |
| * XXX See comment above sys_vfork in sparc64. todo. |
| */ |
| extern void ret_from_fork(void); |
| |
| int copy_thread(unsigned long clone_flags, unsigned long sp, |
| unsigned long unused, |
| struct task_struct *p, struct pt_regs *regs) |
| { |
| struct thread_info *ti = task_thread_info(p); |
| struct pt_regs *childregs; |
| char *new_stack; |
| |
| #ifndef CONFIG_SMP |
| if(last_task_used_math == current) { |
| #else |
| if (test_thread_flag(TIF_USEDFPU)) { |
| #endif |
| put_psr(get_psr() | PSR_EF); |
| fpsave(&p->thread.float_regs[0], &p->thread.fsr, |
| &p->thread.fpqueue[0], &p->thread.fpqdepth); |
| #ifdef CONFIG_SMP |
| clear_thread_flag(TIF_USEDFPU); |
| #endif |
| } |
| |
| /* |
| * p->thread_info new_stack childregs |
| * ! ! ! {if(PSR_PS) } |
| * V V (stk.fr.) V (pt_regs) { (stk.fr.) } |
| * +----- - - - - - ------+===========+============={+==========}+ |
| */ |
| new_stack = task_stack_page(p) + THREAD_SIZE; |
| if (regs->psr & PSR_PS) |
| new_stack -= STACKFRAME_SZ; |
| new_stack -= STACKFRAME_SZ + TRACEREG_SZ; |
| memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ); |
| childregs = (struct pt_regs *) (new_stack + STACKFRAME_SZ); |
| |
| /* |
| * A new process must start with interrupts closed in 2.5, |
| * because this is how Mingo's scheduler works (see schedule_tail |
| * and finish_arch_switch). If we do not do it, a timer interrupt hits |
| * before we unlock, attempts to re-take the rq->lock, and then we die. |
| * Thus, kpsr|=PSR_PIL. |
| */ |
| ti->ksp = (unsigned long) new_stack; |
| ti->kpc = (((unsigned long) ret_from_fork) - 0x8); |
| ti->kpsr = current->thread.fork_kpsr | PSR_PIL; |
| ti->kwim = current->thread.fork_kwim; |
| |
| if(regs->psr & PSR_PS) { |
| extern struct pt_regs fake_swapper_regs; |
| |
| p->thread.kregs = &fake_swapper_regs; |
| new_stack += STACKFRAME_SZ + TRACEREG_SZ; |
| childregs->u_regs[UREG_FP] = (unsigned long) new_stack; |
| p->thread.flags |= SPARC_FLAG_KTHREAD; |
| p->thread.current_ds = KERNEL_DS; |
| memcpy(new_stack, (void *)regs->u_regs[UREG_FP], STACKFRAME_SZ); |
| childregs->u_regs[UREG_G6] = (unsigned long) ti; |
| } else { |
| p->thread.kregs = childregs; |
| childregs->u_regs[UREG_FP] = sp; |
| p->thread.flags &= ~SPARC_FLAG_KTHREAD; |
| p->thread.current_ds = USER_DS; |
| |
| if (sp != regs->u_regs[UREG_FP]) { |
| struct sparc_stackf __user *childstack; |
| struct sparc_stackf __user *parentstack; |
| |
| /* |
| * This is a clone() call with supplied user stack. |
| * Set some valid stack frames to give to the child. |
| */ |
| childstack = (struct sparc_stackf __user *) |
| (sp & ~0xfUL); |
| parentstack = (struct sparc_stackf __user *) |
| regs->u_regs[UREG_FP]; |
| |
| #if 0 |
| printk("clone: parent stack:\n"); |
| show_stackframe(parentstack); |
| #endif |
| |
| childstack = clone_stackframe(childstack, parentstack); |
| if (!childstack) |
| return -EFAULT; |
| |
| #if 0 |
| printk("clone: child stack:\n"); |
| show_stackframe(childstack); |
| #endif |
| |
| childregs->u_regs[UREG_FP] = (unsigned long)childstack; |
| } |
| } |
| |
| #ifdef CONFIG_SMP |
| /* FPU must be disabled on SMP. */ |
| childregs->psr &= ~PSR_EF; |
| #endif |
| |
| /* Set the return value for the child. */ |
| childregs->u_regs[UREG_I0] = current->pid; |
| childregs->u_regs[UREG_I1] = 1; |
| |
| /* Set the return value for the parent. */ |
| regs->u_regs[UREG_I1] = 0; |
| |
| if (clone_flags & CLONE_SETTLS) |
| childregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3]; |
| |
| return 0; |
| } |
| |
| /* |
| * fill in the fpu structure for a core dump. |
| */ |
| int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs) |
| { |
| if (used_math()) { |
| memset(fpregs, 0, sizeof(*fpregs)); |
| fpregs->pr_q_entrysize = 8; |
| return 1; |
| } |
| #ifdef CONFIG_SMP |
| if (test_thread_flag(TIF_USEDFPU)) { |
| put_psr(get_psr() | PSR_EF); |
| fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr, |
| ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth); |
| if (regs != NULL) { |
| regs->psr &= ~(PSR_EF); |
| clear_thread_flag(TIF_USEDFPU); |
| } |
| } |
| #else |
| if (current == last_task_used_math) { |
| put_psr(get_psr() | PSR_EF); |
| fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr, |
| ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth); |
| if (regs != NULL) { |
| regs->psr &= ~(PSR_EF); |
| last_task_used_math = NULL; |
| } |
| } |
| #endif |
| memcpy(&fpregs->pr_fr.pr_regs[0], |
| ¤t->thread.float_regs[0], |
| (sizeof(unsigned long) * 32)); |
| fpregs->pr_fsr = current->thread.fsr; |
| fpregs->pr_qcnt = current->thread.fpqdepth; |
| fpregs->pr_q_entrysize = 8; |
| fpregs->pr_en = 1; |
| if(fpregs->pr_qcnt != 0) { |
| memcpy(&fpregs->pr_q[0], |
| ¤t->thread.fpqueue[0], |
| sizeof(struct fpq) * fpregs->pr_qcnt); |
| } |
| /* Zero out the rest. */ |
| memset(&fpregs->pr_q[fpregs->pr_qcnt], 0, |
| sizeof(struct fpq) * (32 - fpregs->pr_qcnt)); |
| return 1; |
| } |
| |
| /* |
| * sparc_execve() executes a new program after the asm stub has set |
| * things up for us. This should basically do what I want it to. |
| */ |
| asmlinkage int sparc_execve(struct pt_regs *regs) |
| { |
| int error, base = 0; |
| char *filename; |
| |
| /* Check for indirect call. */ |
| if(regs->u_regs[UREG_G1] == 0) |
| base = 1; |
| |
| filename = getname((char __user *)regs->u_regs[base + UREG_I0]); |
| error = PTR_ERR(filename); |
| if(IS_ERR(filename)) |
| goto out; |
| error = do_execve(filename, |
| (char __user * __user *)regs->u_regs[base + UREG_I1], |
| (char __user * __user *)regs->u_regs[base + UREG_I2], |
| regs); |
| putname(filename); |
| out: |
| return error; |
| } |
| |
| /* |
| * This is the mechanism for creating a new kernel thread. |
| * |
| * NOTE! Only a kernel-only process(ie the swapper or direct descendants |
| * who haven't done an "execve()") should use this: it will work within |
| * a system call from a "real" process, but the process memory space will |
| * not be freed until both the parent and the child have exited. |
| */ |
| pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) |
| { |
| long retval; |
| |
| __asm__ __volatile__("mov %4, %%g2\n\t" /* Set aside fn ptr... */ |
| "mov %5, %%g3\n\t" /* and arg. */ |
| "mov %1, %%g1\n\t" |
| "mov %2, %%o0\n\t" /* Clone flags. */ |
| "mov 0, %%o1\n\t" /* usp arg == 0 */ |
| "t 0x10\n\t" /* Linux/Sparc clone(). */ |
| "cmp %%o1, 0\n\t" |
| "be 1f\n\t" /* The parent, just return. */ |
| " nop\n\t" /* Delay slot. */ |
| "jmpl %%g2, %%o7\n\t" /* Call the function. */ |
| " mov %%g3, %%o0\n\t" /* Get back the arg in delay. */ |
| "mov %3, %%g1\n\t" |
| "t 0x10\n\t" /* Linux/Sparc exit(). */ |
| /* Notreached by child. */ |
| "1: mov %%o0, %0\n\t" : |
| "=r" (retval) : |
| "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED), |
| "i" (__NR_exit), "r" (fn), "r" (arg) : |
| "g1", "g2", "g3", "o0", "o1", "memory", "cc"); |
| return retval; |
| } |
| EXPORT_SYMBOL(kernel_thread); |
| |
| unsigned long get_wchan(struct task_struct *task) |
| { |
| unsigned long pc, fp, bias = 0; |
| unsigned long task_base = (unsigned long) task; |
| unsigned long ret = 0; |
| struct reg_window32 *rw; |
| int count = 0; |
| |
| if (!task || task == current || |
| task->state == TASK_RUNNING) |
| goto out; |
| |
| fp = task_thread_info(task)->ksp + bias; |
| do { |
| /* Bogus frame pointer? */ |
| if (fp < (task_base + sizeof(struct thread_info)) || |
| fp >= (task_base + (2 * PAGE_SIZE))) |
| break; |
| rw = (struct reg_window32 *) fp; |
| pc = rw->ins[7]; |
| if (!in_sched_functions(pc)) { |
| ret = pc; |
| goto out; |
| } |
| fp = rw->ins[6] + bias; |
| } while (++count < 16); |
| |
| out: |
| return ret; |
| } |
| |