smp, ARM64: Kill SMP single function call interrupt

Commit 9a46ad6d6df3b54 "smp: make smp_call_function_many() use logic
similar to smp_call_function_single()" has unified the way to handle
single and multiple cross-CPU function calls. Now only one interrupt
is needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/include/asm/hardirq.h

@@ -20,7 +20,7 @@
 #include <linux/threads.h>
 #include <asm/irq.h>
 
-#define NR_IPI	6
+#define NR_IPI	5
 
 typedef struct {
 	unsigned int __softirq_pending;

arch/arm64/kernel/smp.c

@@ -65,7 +65,6 @@ struct secondary_data secondary_data;
 enum ipi_msg_type {
 	IPI_RESCHEDULE,
 	IPI_CALL_FUNC,
-	IPI_CALL_FUNC_SINGLE,
 	IPI_CPU_STOP,
 	IPI_TIMER,
 	IPI_IRQ_WORK,
@@ -483,7 +482,6 @@ static const char *ipi_types[NR_IPI] __tracepoint_string = {
 #define S(x,s)	[x] = s
 	S(IPI_RESCHEDULE, "Rescheduling interrupts"),
 	S(IPI_CALL_FUNC, "Function call interrupts"),
-	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"),
@@ -527,7 +525,7 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask)
 
 void arch_send_call_function_single_ipi(int cpu)
 {
-	smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE);
+	smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC);
 }
 
 #ifdef CONFIG_IRQ_WORK
@@ -585,12 +583,6 @@ void handle_IPI(int ipinr, struct pt_regs *regs)
 		irq_exit();
 		break;
 
-	case IPI_CALL_FUNC_SINGLE:
-		irq_enter();
-		generic_smp_call_function_single_interrupt();
-		irq_exit();
-		break;
-
 	case IPI_CPU_STOP:
 		irq_enter();
 		ipi_cpu_stop(cpu);