summaryrefslogtreecommitdiffstats
path: root/arch/sparc64/kernel/process.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/sparc64/kernel/process.c')
-rw-r--r--arch/sparc64/kernel/process.c177
1 files changed, 156 insertions, 21 deletions
diff --git a/arch/sparc64/kernel/process.c b/arch/sparc64/kernel/process.c
index 05601374915..2084f81a76e 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;
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-28 00:22:19 +0000