LoongArch: Remove generic irq migration

LoongArch inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7362E

--------------------------------

Change-Id: I68a4dfac179ea2575925c3cd256e1179a5934c33
Signed-off-by: NJianmin Lv <lvjianmin@loongson.cn>
Signed-off-by: NJuxin Gao <gaojuxin@loongson.cn>
(cherry picked from commit f24b8441)

arch/loongarch/Kconfig

@@ -395,13 +395,12 @@ config SMP
 config HOTPLUG_CPU
 	bool "Support for hot-pluggable CPUs"
 	depends on SMP
-	select GENERIC_IRQ_MIGRATION
 	help
-	  Say Y here to allow turning CPUs off and on. CPUs can be
-	  controlled through /sys/devices/system/cpu.
-	  (Note: power management support will enable this option
-	    automatically on SMP systems. )
-	  Say N if you want to disable CPU hotplug.
+	Say Y here to allow turning CPUs off and on. CPUs can be
+	controlled through /sys/devices/system/cpu.
+	(Note: power management support will enable this option
+	automatically on SMP systems. )
+	Say N if you want to disable CPU hotplug.
 
 config NR_CPUS
 	int "Maximum number of CPUs (2-256)"

arch/loongarch/include/asm/irq.h

@@ -119,6 +119,7 @@ extern struct fwnode_handle *pch_lpc_handle;
 extern struct fwnode_handle *pch_pic_handle[MAX_IO_PICS];
 
 extern irqreturn_t loongson3_ipi_interrupt(int irq, void *dev);
+extern void fixup_irqs(void);
 
 #include <asm-generic/irq.h>
 

arch/loongarch/kernel/irq.c

@@ -96,6 +96,42 @@ static int __init get_ipi_irq(void)
 	return -EINVAL;
 }
 
+#ifdef CONFIG_HOTPLUG_CPU
+static void handle_irq_affinity(void)
+{
+	struct irq_desc *desc;
+	struct irq_chip *chip;
+	unsigned int irq;
+	unsigned long flags;
+	struct cpumask *affinity;
+
+	for_each_active_irq(irq) {
+		desc = irq_to_desc(irq);
+		if (!desc)
+			continue;
+
+		raw_spin_lock_irqsave(&desc->lock, flags);
+
+		affinity = desc->irq_data.common->affinity;
+		if (!cpumask_intersects(affinity, cpu_online_mask))
+			cpumask_copy(affinity, cpu_online_mask);
+
+		chip = irq_data_get_irq_chip(&desc->irq_data);
+		if (chip && chip->irq_set_affinity)
+			chip->irq_set_affinity(&desc->irq_data,
+					desc->irq_data.common->affinity, true);
+		raw_spin_unlock_irqrestore(&desc->lock, flags);
+	}
+}
+
+void fixup_irqs(void)
+{
+	handle_irq_affinity();
+	irq_cpu_offline();
+	clear_csr_ecfg(ECFG0_IM);
+}
+#endif
+
 void __init init_IRQ(void)
 {
 	int i, ret;

arch/loongarch/kernel/smp.c

@@ -272,8 +272,7 @@ int loongson3_cpu_disable(void)
 	set_cpu_online(cpu, false);
 	calculate_cpu_foreign_map();
 	local_irq_save(flags);
-	irq_migrate_all_off_this_cpu();
-	clear_csr_ecfg(ECFG0_IM);
+	fixup_irqs();
 	local_irq_restore(flags);
 	local_flush_tlb_all();