Re: [PATCH] powerpc/xics: Adjust interrupt receive priority for offline cpus
From: Michael Neuling <hidden>
Date: 2017-02-24 00:22:00
On Thu, 2017-02-23 at 16:24 +0530, Vaidyanathan Srinivasan wrote:
Offline CPUs need to receive IPIs through XIVE when they are in stop state and wakeup from that state. =20 Reduce interrupt receive priority in order to receive XIVE wakeup interrupts when in offline state. =20 LOWEST_PRIORITY would allow all interrupts to be delivered as wakeup events.
This needs to be expanded to explain why "DEFAULT" doesn't work in this cas= e. This also needs an explicit statement that "It fixes onlining of CPUs on POWER9". I'd even advocate for making that the patch subject.=20 Also if it's the right fix, it needs a cc:stable. Mikey
quoted hunk ↗ jump to hunk
Signed-off-by: Vaidyanathan Srinivasan <redacted> --- =C2=A0arch/powerpc/sysdev/xics/xics-common.c | 2 +- =C2=A01 file changed, 1 insertion(+), 1 deletion(-) =20diff --git a/arch/powerpc/sysdev/xics/xics-common.cb/arch/powerpc/sysdev/xics/xics-common.c index 69d858e..c674a9d 100644--- a/arch/powerpc/sysdev/xics/xics-common.c +++ b/arch/powerpc/sysdev/xics/xics-common.c@@ -199,7 +199,7 @@ void xics_migrate_irqs_away(void)=C2=A0 xics_set_cpu_giq(xics_default_distrib_server, 0); =C2=A0 =C2=A0 /* Allow IPIs again... */ - icp_ops->set_priority(DEFAULT_PRIORITY); + icp_ops->set_priority(LOWEST_PRIORITY); =C2=A0 =C2=A0 for_each_irq_desc(virq, desc) { =C2=A0 struct irq_chip *chip;