#include <linux/kernel.h>
#include <linux/tracehook.h>
#include <linux/signal.h>
+#include <linux/delay.h>
#include <linux/context_tracking.h>
#include <asm/stack.h>
#include <asm/switch_to.h>
(CALLEE_SAVED_REGS_COUNT - 2) * sizeof(unsigned long));
callee_regs[0] = sp; /* r30 = function */
callee_regs[1] = arg; /* r31 = arg */
- childregs->ex1 = PL_ICS_EX1(KERNEL_PL, 0);
p->thread.pc = (unsigned long) ret_from_kernel_thread;
return 0;
}
hardwall_switch_tasks(prev, next);
#endif
+ /* Notify the simulator of task exit. */
+ if (unlikely(prev->state == TASK_DEAD))
+ __insn_mtspr(SPR_SIM_CONTROL, SIM_CONTROL_OS_EXIT |
+ (prev->pid << _SIM_CONTROL_OPERATOR_BITS));
+
/*
* Switch kernel SP, PC, and callee-saved registers.
* In the context of the new task, return the old task pointer
#endif
}
-void show_regs(struct pt_regs *regs)
+void tile_show_regs(struct pt_regs *regs)
{
- struct task_struct *tsk = validate_current();
int i;
-
- if (tsk != &corrupt_current)
- show_regs_print_info(KERN_ERR);
#ifdef __tilegx__
for (i = 0; i < 17; i++)
- pr_err(" r%-2d: " REGFMT " r%-2d: " REGFMT " r%-2d: " REGFMT "\n",
+ pr_err(" r%-2d: "REGFMT" r%-2d: "REGFMT" r%-2d: "REGFMT"\n",
i, regs->regs[i], i+18, regs->regs[i+18],
i+36, regs->regs[i+36]);
- pr_err(" r17: " REGFMT " r35: " REGFMT " tp : " REGFMT "\n",
+ pr_err(" r17: "REGFMT" r35: "REGFMT" tp : "REGFMT"\n",
regs->regs[17], regs->regs[35], regs->tp);
- pr_err(" sp : " REGFMT " lr : " REGFMT "\n", regs->sp, regs->lr);
+ pr_err(" sp : "REGFMT" lr : "REGFMT"\n", regs->sp, regs->lr);
#else
for (i = 0; i < 13; i++)
- pr_err(" r%-2d: " REGFMT " r%-2d: " REGFMT " r%-2d: " REGFMT " r%-2d: " REGFMT "\n",
+ pr_err(" r%-2d: "REGFMT" r%-2d: "REGFMT
+ " r%-2d: "REGFMT" r%-2d: "REGFMT"\n",
i, regs->regs[i], i+14, regs->regs[i+14],
i+27, regs->regs[i+27], i+40, regs->regs[i+40]);
- pr_err(" r13: " REGFMT " tp : " REGFMT " sp : " REGFMT " lr : " REGFMT "\n",
+ pr_err(" r13: "REGFMT" tp : "REGFMT" sp : "REGFMT" lr : "REGFMT"\n",
regs->regs[13], regs->tp, regs->sp, regs->lr);
#endif
- pr_err(" pc : " REGFMT " ex1: %ld faultnum: %ld\n",
- regs->pc, regs->ex1, regs->faultnum);
+ pr_err(" pc : "REGFMT" ex1: %ld faultnum: %ld flags:%s%s%s%s\n",
+ regs->pc, regs->ex1, regs->faultnum,
+ is_compat_task() ? " compat" : "",
+ (regs->flags & PT_FLAGS_DISABLE_IRQ) ? " noirq" : "",
+ !(regs->flags & PT_FLAGS_CALLER_SAVES) ? " nocallersave" : "",
+ (regs->flags & PT_FLAGS_RESTORE_REGS) ? " restoreregs" : "");
+}
+
+void show_regs(struct pt_regs *regs)
+{
+ struct KBacktraceIterator kbt;
+
+ show_regs_print_info(KERN_DEFAULT);
+ tile_show_regs(regs);
+
+ KBacktraceIterator_init(&kbt, NULL, regs);
+ tile_show_stack(&kbt);
+}
- dump_stack_regs(regs);
+/* To ensure stack dump on tiles occurs one by one. */
+static DEFINE_SPINLOCK(backtrace_lock);
+/* To ensure no backtrace occurs before all of the stack dump are done. */
+static atomic_t backtrace_cpus;
+/* The cpu mask to avoid reentrance. */
+static struct cpumask backtrace_mask;
+
+void do_nmi_dump_stack(struct pt_regs *regs)
+{
+ int is_idle = is_idle_task(current) && !in_interrupt();
+ int cpu;
+
+ nmi_enter();
+ cpu = smp_processor_id();
+ if (WARN_ON_ONCE(!cpumask_test_and_clear_cpu(cpu, &backtrace_mask)))
+ goto done;
+
+ spin_lock(&backtrace_lock);
+ if (is_idle)
+ pr_info("CPU: %d idle\n", cpu);
+ else
+ show_regs(regs);
+ spin_unlock(&backtrace_lock);
+ atomic_dec(&backtrace_cpus);
+done:
+ nmi_exit();
+}
+
+#ifdef __tilegx__
+void arch_trigger_all_cpu_backtrace(bool self)
+{
+ struct cpumask mask;
+ HV_Coord tile;
+ unsigned int timeout;
+ int cpu;
+ int ongoing;
+ HV_NMI_Info info[NR_CPUS];
+
+ ongoing = atomic_cmpxchg(&backtrace_cpus, 0, num_online_cpus() - 1);
+ if (ongoing != 0) {
+ pr_err("Trying to do all-cpu backtrace.\n");
+ pr_err("But another all-cpu backtrace is ongoing (%d cpus left)\n",
+ ongoing);
+ if (self) {
+ pr_err("Reporting the stack on this cpu only.\n");
+ dump_stack();
+ }
+ return;
+ }
+
+ cpumask_copy(&mask, cpu_online_mask);
+ cpumask_clear_cpu(smp_processor_id(), &mask);
+ cpumask_copy(&backtrace_mask, &mask);
+
+ /* Backtrace for myself first. */
+ if (self)
+ dump_stack();
+
+ /* Tentatively dump stack on remote tiles via NMI. */
+ timeout = 100;
+ while (!cpumask_empty(&mask) && timeout) {
+ for_each_cpu(cpu, &mask) {
+ tile.x = cpu_x(cpu);
+ tile.y = cpu_y(cpu);
+ info[cpu] = hv_send_nmi(tile, TILE_NMI_DUMP_STACK, 0);
+ if (info[cpu].result == HV_NMI_RESULT_OK)
+ cpumask_clear_cpu(cpu, &mask);
+ }
+
+ mdelay(10);
+ timeout--;
+ }
+
+ /* Warn about cpus stuck in ICS and decrement their counts here. */
+ if (!cpumask_empty(&mask)) {
+ for_each_cpu(cpu, &mask) {
+ switch (info[cpu].result) {
+ case HV_NMI_RESULT_FAIL_ICS:
+ pr_warn("Skipping stack dump of cpu %d in ICS at pc %#llx\n",
+ cpu, info[cpu].pc);
+ break;
+ case HV_NMI_RESULT_FAIL_HV:
+ pr_warn("Skipping stack dump of cpu %d in hypervisor\n",
+ cpu);
+ break;
+ case HV_ENOSYS:
+ pr_warn("Hypervisor too old to allow remote stack dumps.\n");
+ goto skip_for_each;
+ default: /* should not happen */
+ pr_warn("Skipping stack dump of cpu %d [%d,%#llx]\n",
+ cpu, info[cpu].result, info[cpu].pc);
+ break;
+ }
+ }
+skip_for_each:
+ atomic_sub(cpumask_weight(&mask), &backtrace_cpus);
+ }
}
+#endif /* __tilegx_ */
Code Review / kvmfornfv.git / blobdiff