summaryrefslogtreecommitdiff
path: root/arch
diff options
context:
space:
mode:
authorPaul Clarke <pc@us.ibm.com>2015-02-20 11:13:33 -0600
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2015-04-19 10:10:16 +0200
commit74b8c182c346ec27594a522e24bb0608d20d8b5a (patch)
tree634a5290e2efe38e9a7809b630e357ec0934a4f4 /arch
parent4ab14323dfb7de200cbb913030e5fa871e6351c8 (diff)
downloadlwn-74b8c182c346ec27594a522e24bb0608d20d8b5a.tar.gz
lwn-74b8c182c346ec27594a522e24bb0608d20d8b5a.zip
powerpc: Re-enable dynticks
commit fea559f303567e558bfab9c8ba4a2af5b309205a upstream. 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
-rw-r--r--arch/powerpc/include/asm/irq_work.h9
1 files changed, 9 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/irq_work.h b/arch/powerpc/include/asm/irq_work.h
new file mode 100644
index 000000000000..744fd54de374
--- /dev/null
+++ b/arch/powerpc/include/asm/irq_work.h
@@ -0,0 +1,9 @@
+#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 */