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-rw-r--r--arch/arm64/kernel/smp.c41
1 files changed, 41 insertions, 0 deletions
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index f0a141dd5655..40f38f46c8e0 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -35,6 +35,7 @@
#include <linux/clockchips.h>
#include <linux/completion.h>
#include <linux/of.h>
+#include <linux/irq_work.h>
#include <asm/atomic.h>
#include <asm/cacheflush.h>
@@ -62,6 +63,7 @@ enum ipi_msg_type {
IPI_CALL_FUNC_SINGLE,
IPI_CPU_STOP,
IPI_TIMER,
+ IPI_IRQ_WORK,
};
/*
@@ -228,6 +230,19 @@ int __cpu_disable(void)
return 0;
}
+static int op_cpu_kill(unsigned int cpu)
+{
+ /*
+ * If we have no means of synchronising with the dying CPU, then assume
+ * that it is really dead. We can only wait for an arbitrary length of
+ * time and hope that it's dead, so let's skip the wait and just hope.
+ */
+ if (!cpu_ops[cpu]->cpu_kill)
+ return 1;
+
+ return cpu_ops[cpu]->cpu_kill(cpu);
+}
+
static DECLARE_COMPLETION(cpu_died);
/*
@@ -241,6 +256,15 @@ void __cpu_die(unsigned int cpu)
return;
}
pr_notice("CPU%u: shutdown\n", cpu);
+
+ /*
+ * Now that the dying CPU is beyond the point of no return w.r.t.
+ * in-kernel synchronisation, try to get the firwmare to help us to
+ * verify that it has really left the kernel before we consider
+ * clobbering anything it might still be using.
+ */
+ if (!op_cpu_kill(cpu))
+ pr_warn("CPU%d may not have shut down cleanly\n", cpu);
}
/*
@@ -455,6 +479,14 @@ void arch_send_call_function_single_ipi(int cpu)
smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE);
}
+#ifdef CONFIG_IRQ_WORK
+void arch_irq_work_raise(void)
+{
+ if (smp_cross_call)
+ smp_cross_call(cpumask_of(smp_processor_id()), IPI_IRQ_WORK);
+}
+#endif
+
static const char *ipi_types[NR_IPI] = {
#define S(x,s) [x - IPI_RESCHEDULE] = s
S(IPI_RESCHEDULE, "Rescheduling interrupts"),
@@ -462,6 +494,7 @@ static const char *ipi_types[NR_IPI] = {
S(IPI_CALL_FUNC_SINGLE, "Single function call interrupts"),
S(IPI_CPU_STOP, "CPU stop interrupts"),
S(IPI_TIMER, "Timer broadcast interrupts"),
+ S(IPI_IRQ_WORK, "IRQ work interrupts"),
};
void show_ipi_list(struct seq_file *p, int prec)
@@ -554,6 +587,14 @@ void handle_IPI(int ipinr, struct pt_regs *regs)
break;
#endif
+#ifdef CONFIG_IRQ_WORK
+ case IPI_IRQ_WORK:
+ irq_enter();
+ irq_work_run();
+ irq_exit();
+ break;
+#endif
+
default:
pr_crit("CPU%u: Unknown IPI message 0x%x\n", cpu, ipinr);
break;