diff options
Diffstat (limited to 'arch/sparc64/kernel/process.c')
-rw-r--r-- | arch/sparc64/kernel/process.c | 177 |
1 files changed, 156 insertions, 21 deletions
diff --git a/arch/sparc64/kernel/process.c b/arch/sparc64/kernel/process.c index 0560137..2084f81 100644 --- a/arch/sparc64/kernel/process.c +++ b/arch/sparc64/kernel/process.c @@ -1,6 +1,6 @@ /* arch/sparc64/kernel/process.c * - * Copyright (C) 1995, 1996 David S. Miller (davem@caip.rutgers.edu) + * Copyright (C) 1995, 1996, 2008 David S. Miller (davem@davemloft.net) * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be) * Copyright (C) 1997, 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz) */ @@ -30,6 +30,7 @@ #include <linux/init.h> #include <linux/cpu.h> #include <linux/elfcore.h> +#include <linux/sysrq.h> #include <asm/oplib.h> #include <asm/uaccess.h> @@ -49,6 +50,8 @@ #include <asm/sstate.h> #include <asm/reboot.h> #include <asm/syscalls.h> +#include <asm/irq_regs.h> +#include <asm/smp.h> /* #define VERBOSE_SHOWREGS */ @@ -298,6 +301,118 @@ void show_regs(struct pt_regs *regs) #endif } +#ifdef CONFIG_MAGIC_SYSRQ +struct global_reg_snapshot global_reg_snapshot[NR_CPUS]; +static DEFINE_SPINLOCK(global_reg_snapshot_lock); + +static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs, + int this_cpu) +{ + flushw_all(); + + global_reg_snapshot[this_cpu].tstate = regs->tstate; + global_reg_snapshot[this_cpu].tpc = regs->tpc; + global_reg_snapshot[this_cpu].tnpc = regs->tnpc; + global_reg_snapshot[this_cpu].o7 = regs->u_regs[UREG_I7]; + + if (regs->tstate & TSTATE_PRIV) { + struct reg_window *rw; + + rw = (struct reg_window *) + (regs->u_regs[UREG_FP] + STACK_BIAS); + global_reg_snapshot[this_cpu].i7 = rw->ins[6]; + } else + global_reg_snapshot[this_cpu].i7 = 0; + + global_reg_snapshot[this_cpu].thread = tp; +} + +/* In order to avoid hangs we do not try to synchronize with the + * global register dump client cpus. The last store they make is to + * the thread pointer, so do a short poll waiting for that to become + * non-NULL. + */ +static void __global_reg_poll(struct global_reg_snapshot *gp) +{ + int limit = 0; + + while (!gp->thread && ++limit < 100) { + barrier(); + udelay(1); + } +} + +static void sysrq_handle_globreg(int key, struct tty_struct *tty) +{ + struct thread_info *tp = current_thread_info(); + struct pt_regs *regs = get_irq_regs(); +#ifdef CONFIG_KALLSYMS + char buffer[KSYM_SYMBOL_LEN]; +#endif + unsigned long flags; + int this_cpu, cpu; + + if (!regs) + regs = tp->kregs; + + spin_lock_irqsave(&global_reg_snapshot_lock, flags); + + memset(global_reg_snapshot, 0, sizeof(global_reg_snapshot)); + + this_cpu = raw_smp_processor_id(); + + __global_reg_self(tp, regs, this_cpu); + + smp_fetch_global_regs(); + + for_each_online_cpu(cpu) { + struct global_reg_snapshot *gp = &global_reg_snapshot[cpu]; + struct thread_info *tp; + + __global_reg_poll(gp); + + tp = gp->thread; + printk("%c CPU[%3d]: TSTATE[%016lx] TPC[%016lx] TNPC[%016lx] TASK[%s:%d]\n", + (cpu == this_cpu ? '*' : ' '), cpu, + gp->tstate, gp->tpc, gp->tnpc, + ((tp && tp->task) ? tp->task->comm : "NULL"), + ((tp && tp->task) ? tp->task->pid : -1)); +#ifdef CONFIG_KALLSYMS + if (gp->tstate & TSTATE_PRIV) { + sprint_symbol(buffer, gp->tpc); + printk(" TPC[%s] ", buffer); + sprint_symbol(buffer, gp->o7); + printk("O7[%s] ", buffer); + sprint_symbol(buffer, gp->i7); + printk("I7[%s]\n", buffer); + } else +#endif + { + printk(" TPC[%lx] O7[%lx] I7[%lx]\n", + gp->tpc, gp->o7, gp->i7); + } + } + + memset(global_reg_snapshot, 0, sizeof(global_reg_snapshot)); + + spin_unlock_irqrestore(&global_reg_snapshot_lock, flags); +} + +static struct sysrq_key_op sparc_globalreg_op = { + .handler = sysrq_handle_globreg, + .help_msg = "Globalregs", + .action_msg = "Show Global CPU Regs", +}; + +static int __init sparc_globreg_init(void) +{ + return register_sysrq_key('y', &sparc_globalreg_op); +} + +core_initcall(sparc_globreg_init); + +#endif + unsigned long thread_saved_pc(struct task_struct *tsk) { struct thread_info *ti = task_thread_info(tsk); @@ -503,6 +618,8 @@ asmlinkage long sparc_do_fork(unsigned long clone_flags, unsigned long stack_size) { int __user *parent_tid_ptr, *child_tid_ptr; + unsigned long orig_i1 = regs->u_regs[UREG_I1]; + long ret; #ifdef CONFIG_COMPAT if (test_thread_flag(TIF_32BIT)) { @@ -515,9 +632,19 @@ asmlinkage long sparc_do_fork(unsigned long clone_flags, child_tid_ptr = (int __user *) regs->u_regs[UREG_I4]; } - return do_fork(clone_flags, stack_start, - regs, stack_size, - parent_tid_ptr, child_tid_ptr); + ret = do_fork(clone_flags, stack_start, + regs, stack_size, + parent_tid_ptr, 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 @@ -530,20 +657,39 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long sp, struct task_struct *p, struct pt_regs *regs) { struct thread_info *t = task_thread_info(p); + struct sparc_stackf *parent_sf; + unsigned long child_stack_sz; char *child_trap_frame; + int kernel_thread; - /* Calculate offset to stack_frame & pt_regs */ - child_trap_frame = task_stack_page(p) + (THREAD_SIZE - (TRACEREG_SZ+STACKFRAME_SZ)); - memcpy(child_trap_frame, (((struct sparc_stackf *)regs)-1), (TRACEREG_SZ+STACKFRAME_SZ)); + kernel_thread = (regs->tstate & TSTATE_PRIV) ? 1 : 0; + parent_sf = ((struct sparc_stackf *) regs) - 1; - t->flags = (t->flags & ~((0xffUL << TI_FLAG_CWP_SHIFT) | (0xffUL << TI_FLAG_CURRENT_DS_SHIFT))) | + /* Calculate offset to stack_frame & pt_regs */ + child_stack_sz = ((STACKFRAME_SZ + TRACEREG_SZ) + + (kernel_thread ? STACKFRAME_SZ : 0)); + child_trap_frame = (task_stack_page(p) + + (THREAD_SIZE - child_stack_sz)); + memcpy(child_trap_frame, parent_sf, child_stack_sz); + + t->flags = (t->flags & ~((0xffUL << TI_FLAG_CWP_SHIFT) | + (0xffUL << TI_FLAG_CURRENT_DS_SHIFT))) | (((regs->tstate + 1) & TSTATE_CWP) << TI_FLAG_CWP_SHIFT); t->new_child = 1; t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS; - t->kregs = (struct pt_regs *)(child_trap_frame+sizeof(struct sparc_stackf)); + t->kregs = (struct pt_regs *) (child_trap_frame + + sizeof(struct sparc_stackf)); t->fpsaved[0] = 0; - if (regs->tstate & TSTATE_PRIV) { + if (kernel_thread) { + struct sparc_stackf *child_sf = (struct sparc_stackf *) + (child_trap_frame + (STACKFRAME_SZ + TRACEREG_SZ)); + + /* Zero terminate the stack backtrace. */ + child_sf->fp = NULL; + t->kregs->u_regs[UREG_FP] = + ((unsigned long) child_sf) - STACK_BIAS; + /* Special case, if we are spawning a kernel thread from * a userspace task (via KMOD, NFS, or similar) we must * disable performance counters in the child because the @@ -554,12 +700,7 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long sp, t->pcr_reg = 0; t->flags &= ~_TIF_PERFCTR; } - t->kregs->u_regs[UREG_FP] = t->ksp; t->flags |= ((long)ASI_P << TI_FLAG_CURRENT_DS_SHIFT); - flush_register_windows(); - memcpy((void *)(t->ksp + STACK_BIAS), - (void *)(regs->u_regs[UREG_FP] + STACK_BIAS), - sizeof(struct sparc_stackf)); t->kregs->u_regs[UREG_G6] = (unsigned long) t; t->kregs->u_regs[UREG_G4] = (unsigned long) t->task; } else { @@ -591,12 +732,6 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long sp, if (clone_flags & CLONE_SETTLS) t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3]; - /* We do not want to accidently trigger system call restart - * handling in the new thread. Therefore, clear out the trap - * type, which will make pt_regs_regs_is_syscall() return false. - */ - pt_regs_clear_trap_type(t->kregs); - return 0; } |