[ Upstream commit
fea559f303567e558bfab9c8ba4a2af5b309205a ]
Implement arch_irq_work_has_interrupt() for powerpc
Commit
9b01f5bf3 introduced a dependency on "IRQ work self-IPIs" for
full dynamic ticks to be enabled, by expecting architectures to
implement a suitable arch_irq_work_has_interrupt() routine.
Several arches have implemented this routine, including x86 (
3010279f)
and arm (
09f6edd4), but powerpc was omitted.
This patch implements this routine for powerpc.
The symptom, at boot (on powerpc systems) with "nohz_full=<CPU list>"
is displayed:
NO_HZ: Can't run full dynticks because arch doesn't support irq work self-IPIs
after this patch:
NO_HZ: Full dynticks CPUs: <CPU list>.
Tested against 3.19.
powerpc implements "IRQ work self-IPIs" by setting the decrementer to 1 in
arch_irq_work_raise(), which causes a decrementer exception on the next
timebase tick. We then handle the work in __timer_interrupt().
CC: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Paul A. Clarke <pc@us.ibm.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[mpe: Flesh out change log, fix ws & include guards, remove include of processor.h]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
--- /dev/null
+#ifndef _ASM_POWERPC_IRQ_WORK_H
+#define _ASM_POWERPC_IRQ_WORK_H
+
+static inline bool arch_irq_work_has_interrupt(void)
+{
+ return true;
+}
+
+#endif /* _ASM_POWERPC_IRQ_WORK_H */