MIPS: Loongson: Oprofile: add a new do_perfcnt_IRQ()

On FuLoong-2F IP6 is shared by the performance counter overflow interrupt
and the Bonito northbridge interrupt.  To reduce overhead only call
do_IRQ() when oprofile is enabled to reduce overhead.

This patch adds an inline function do_perfcnt_IRQ() to hide the #if's ,
which can be shared by the other Loongson machines, i.e. gdium.
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1492/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/include/asm/mach-loongson/loongson.h

@@ -62,6 +62,14 @@ extern int mach_i8259_irq(void);
 #define LOONGSON_IRQ_BASE	32
 #define LOONGSON2_PERFCNT_IRQ	(MIPS_CPU_IRQ_BASE + 6) /* cpu perf counter */
 
+#include <linux/interrupt.h>
+static inline void do_perfcnt_IRQ(void)
+{
+#if defined(CONFIG_OPROFILE) || defined(CONFIG_OPROFILE_MODULE)
+	do_IRQ(LOONGSON2_PERFCNT_IRQ);
+#endif
+}
+
 #define LOONGSON_FLASH_BASE	0x1c000000
 #define LOONGSON_FLASH_SIZE	0x02000000	/* 32M */
 #define LOONGSON_FLASH_TOP	(LOONGSON_FLASH_BASE+LOONGSON_FLASH_SIZE-1)

arch/mips/loongson/fuloong-2e/irq.c

@@ -30,7 +30,7 @@ asmlinkage void mach_irq_dispatch(unsigned int pending)
 	if (pending & CAUSEF_IP7)
 		do_IRQ(MIPS_CPU_IRQ_BASE + 7);
 	else if (pending & CAUSEF_IP6) /* perf counter loverflow */
-		do_IRQ(LOONGSON2_PERFCNT_IRQ);
+		do_perfcnt_IRQ();
 	else if (pending & CAUSEF_IP5)
 		i8259_irqdispatch();
 	else if (pending & CAUSEF_IP2)

arch/mips/loongson/lemote-2f/irq.c

@@ -79,9 +79,7 @@ void mach_irq_dispatch(unsigned int pending)
 	if (pending & CAUSEF_IP7)
 		do_IRQ(LOONGSON_TIMER_IRQ);
 	else if (pending & CAUSEF_IP6) {	/* North Bridge, Perf counter */
-#if defined(CONFIG_OPROFILE) || defined(CONFIG_OPROFILE_MODULE)
-		do_IRQ(LOONGSON2_PERFCNT_IRQ);
-#endif
+		do_perfcnt_IRQ();
 		bonito_irqdispatch();
 	} else if (pending & CAUSEF_IP3)	/* CPU UART */
 		do_IRQ(LOONGSON_UART_IRQ);