irq_work: Introduce arch_irq_work_has_interrupt()

The nohz full code needs irq work to trigger its own interrupt so that
the subsystem can work even when the tick is stopped.

Lets introduce arch_irq_work_has_interrupt() that archs can override to
tell about their support for this ability.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>

arch/alpha/include/asm/Kbuild

@@ -4,6 +4,7 @@ generic-y += clkdev.h
 generic-y += cputime.h
 generic-y += exec.h
 generic-y += hash.h
+generic-y += irq_work.h
 generic-y += mcs_spinlock.h
 generic-y += preempt.h
 generic-y += scatterlist.h

arch/arc/include/asm/Kbuild

@@ -18,6 +18,7 @@ generic-y += ioctl.h
 generic-y += ioctls.h
 generic-y += ipcbuf.h
 generic-y += irq_regs.h
+generic-y += irq_work.h
 generic-y += kmap_types.h
 generic-y += kvm_para.h
 generic-y += local.h

arch/arm/include/asm/Kbuild

@@ -11,6 +11,7 @@ generic-y += hash.h
 generic-y += ioctl.h
 generic-y += ipcbuf.h
 generic-y += irq_regs.h
+generic-y += irq_work.h
 generic-y += kdebug.h
 generic-y += local.h
 generic-y += local64.h

arch/arm64/include/asm/Kbuild

@@ -9,8 +9,8 @@ generic-y += current.h
 generic-y += delay.h
 generic-y += div64.h
 generic-y += dma.h
-generic-y += emergency-restart.h
 generic-y += early_ioremap.h
+generic-y += emergency-restart.h
 generic-y += errno.h
 generic-y += ftrace.h
 generic-y += hash.h
@@ -19,6 +19,7 @@ generic-y += ioctl.h
 generic-y += ioctls.h
 generic-y += ipcbuf.h
 generic-y += irq_regs.h
+generic-y += irq_work.h
 generic-y += kdebug.h
 generic-y += kmap_types.h
 generic-y += kvm_para.h

arch/avr32/include/asm/Kbuild

@@ -9,6 +9,7 @@ generic-y += exec.h
 generic-y += futex.h
 generic-y += hash.h
 generic-y += irq_regs.h
+generic-y += irq_work.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h

arch/blackfin/include/asm/Kbuild

@@ -15,6 +15,7 @@ generic-y += hw_irq.h
 generic-y += ioctl.h
 generic-y += ipcbuf.h
 generic-y += irq_regs.h
+generic-y += irq_work.h
 generic-y += kdebug.h
 generic-y += kmap_types.h
 generic-y += kvm_para.h

arch/c6x/include/asm/Kbuild

@@ -22,6 +22,7 @@ generic-y += ioctl.h
 generic-y += ioctls.h
 generic-y += ipcbuf.h
 generic-y += irq_regs.h
+generic-y += irq_work.h
 generic-y += kdebug.h
 generic-y += kmap_types.h
 generic-y += local.h

arch/cris/include/asm/Kbuild

@@ -8,6 +8,7 @@ generic-y += clkdev.h
 generic-y += cputime.h
 generic-y += exec.h
 generic-y += hash.h
+generic-y += irq_work.h
 generic-y += kvm_para.h
 generic-y += linkage.h
 generic-y += mcs_spinlock.h

arch/frv/include/asm/Kbuild

@@ -3,6 +3,7 @@ generic-y += clkdev.h
 generic-y += cputime.h
 generic-y += exec.h
 generic-y += hash.h
+generic-y += irq_work.h
 generic-y += mcs_spinlock.h
 generic-y += preempt.h
 generic-y += scatterlist.h

arch/hexagon/include/asm/Kbuild

@@ -23,6 +23,7 @@ generic-y += ioctls.h
 generic-y += iomap.h
 generic-y += ipcbuf.h
 generic-y += irq_regs.h
+generic-y += irq_work.h
 generic-y += kdebug.h
 generic-y += kmap_types.h
 generic-y += local.h

arch/ia64/include/asm/Kbuild

@@ -2,6 +2,7 @@
 generic-y += clkdev.h
 generic-y += exec.h
 generic-y += hash.h
+generic-y += irq_work.h
 generic-y += kvm_para.h
 generic-y += mcs_spinlock.h
 generic-y += preempt.h

arch/m32r/include/asm/Kbuild

@@ -3,6 +3,7 @@ generic-y += clkdev.h
 generic-y += cputime.h
 generic-y += exec.h
 generic-y += hash.h
+generic-y += irq_work.h
 generic-y += mcs_spinlock.h
 generic-y += module.h
 generic-y += preempt.h

arch/m68k/include/asm/Kbuild

@@ -11,6 +11,7 @@ generic-y += hw_irq.h
 generic-y += ioctl.h
 generic-y += ipcbuf.h
 generic-y += irq_regs.h
+generic-y += irq_work.h
 generic-y += kdebug.h
 generic-y += kmap_types.h
 generic-y += kvm_para.h

arch/metag/include/asm/Kbuild

@@ -19,6 +19,7 @@ generic-y += ioctl.h
 generic-y += ioctls.h
 generic-y += ipcbuf.h
 generic-y += irq_regs.h
+generic-y += irq_work.h
 generic-y += kdebug.h
 generic-y += kmap_types.h
 generic-y += kvm_para.h

arch/microblaze/include/asm/Kbuild

@@ -5,6 +5,7 @@ generic-y += cputime.h
 generic-y += device.h
 generic-y += exec.h
 generic-y += hash.h
+generic-y += irq_work.h
 generic-y += mcs_spinlock.h
 generic-y += preempt.h
 generic-y += scatterlist.h

arch/mips/include/asm/Kbuild

@@ -3,6 +3,7 @@ generic-y += cputime.h
 generic-y += current.h
 generic-y += emergency-restart.h
 generic-y += hash.h
+generic-y += irq_work.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
 generic-y += mutex.h

arch/mn10300/include/asm/Kbuild

@@ -4,6 +4,7 @@ generic-y += clkdev.h
 generic-y += cputime.h
 generic-y += exec.h
 generic-y += hash.h
+generic-y += irq_work.h
 generic-y += mcs_spinlock.h
 generic-y += preempt.h
 generic-y += scatterlist.h

arch/openrisc/include/asm/Kbuild

@@ -31,6 +31,7 @@ generic-y += ioctl.h
 generic-y += ioctls.h
 generic-y += ipcbuf.h
 generic-y += irq_regs.h
+generic-y += irq_work.h
 generic-y += kdebug.h
 generic-y += kmap_types.h
 generic-y += kvm_para.h

arch/parisc/include/asm/Kbuild

@@ -10,6 +10,7 @@ generic-y += exec.h
 generic-y += hash.h
 generic-y += hw_irq.h
 generic-y += irq_regs.h
+generic-y += irq_work.h
 generic-y += kdebug.h
 generic-y += kvm_para.h
 generic-y += local.h

arch/powerpc/include/asm/Kbuild

@@ -1,6 +1,7 @@
 
 generic-y += clkdev.h
 generic-y += hash.h
+generic-y += irq_work.h
 generic-y += mcs_spinlock.h
 generic-y += preempt.h
 generic-y += rwsem.h

arch/s390/include/asm/Kbuild

@@ -2,6 +2,7 @@
 
 generic-y += clkdev.h
 generic-y += hash.h
+generic-y += irq_work.h
 generic-y += mcs_spinlock.h
 generic-y += preempt.h
 generic-y += scatterlist.h

arch/score/include/asm/Kbuild

@@ -6,6 +6,7 @@ generic-y += barrier.h
 generic-y += clkdev.h
 generic-y += cputime.h
 generic-y += hash.h
+generic-y += irq_work.h
 generic-y += mcs_spinlock.h
 generic-y += preempt.h
 generic-y += scatterlist.h

arch/sh/include/asm/Kbuild

@@ -12,6 +12,7 @@ generic-y += hash.h
 generic-y += ioctl.h
 generic-y += ipcbuf.h
 generic-y += irq_regs.h
+generic-y += irq_work.h
 generic-y += kvm_para.h
 generic-y += local.h
 generic-y += local64.h

arch/sparc/include/asm/Kbuild

@@ -8,6 +8,7 @@ generic-y += emergency-restart.h
 generic-y += exec.h
 generic-y += hash.h
 generic-y += irq_regs.h
+generic-y += irq_work.h
 generic-y += linkage.h
 generic-y += local.h
 generic-y += local64.h

arch/tile/include/asm/Kbuild

@@ -17,6 +17,7 @@ generic-y += ioctl.h
 generic-y += ioctls.h
 generic-y += ipcbuf.h
 generic-y += irq_regs.h
+generic-y += irq_work.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h

arch/um/include/asm/Kbuild

@@ -14,6 +14,7 @@ generic-y += hash.h
 generic-y += hw_irq.h
 generic-y += io.h
 generic-y += irq_regs.h
+generic-y += irq_work.h
 generic-y += kdebug.h
 generic-y += mcs_spinlock.h
 generic-y += mutex.h

arch/unicore32/include/asm/Kbuild

@@ -22,6 +22,7 @@ generic-y += ioctl.h
 generic-y += ioctls.h
 generic-y += ipcbuf.h
 generic-y += irq_regs.h
+generic-y += irq_work.h
 generic-y += kdebug.h
 generic-y += kmap_types.h
 generic-y += local.h

arch/x86/include/asm/Kbuild

@@ -7,5 +7,6 @@ genhdr-y += unistd_x32.h
 generic-y += clkdev.h
 generic-y += cputime.h
 generic-y += early_ioremap.h
+generic-y += irq_work.h
 generic-y += mcs_spinlock.h
 generic-y += scatterlist.h

arch/xtensa/include/asm/Kbuild

@@ -12,6 +12,7 @@ generic-y += hardirq.h
 generic-y += hash.h
 generic-y += ioctl.h
 generic-y += irq_regs.h
+generic-y += irq_work.h
 generic-y += kdebug.h
 generic-y += kmap_types.h
 generic-y += kvm_para.h

include/asm-generic/irq_work.h

@@ -0,0 +1,10 @@
+#ifndef __ASM_IRQ_WORK_H
+#define __ASM_IRQ_WORK_H
+
+static inline bool arch_irq_work_has_interrupt(void)
+{
+	return false;
+}
+
+#endif /* __ASM_IRQ_WORK_H */
+

include/linux/irq_work.h

@@ -42,6 +42,8 @@ void irq_work_run(void);
 void irq_work_sync(struct irq_work *work);
 
 #ifdef CONFIG_IRQ_WORK
+#include <asm/irq_work.h>
+
 bool irq_work_needs_cpu(void);
 #else
 static inline bool irq_work_needs_cpu(void) { return false; }