From: Jan Beulich Date: Fri, 27 Dec 2019 08:53:35 +0000 (+0100) Subject: x86/IRQ: simplify pending EOI stack logic for internally used IRQs X-Git-Tag: archive/raspbian/4.14.0+80-gd101b417b7-1+rpi1^2~63^2~969 X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=53fd9dafeb5a7601bdfb090a631bafbbd3c84fe3;p=xen.git x86/IRQ: simplify pending EOI stack logic for internally used IRQs In 5655ce8b1ec2 ("x86/IRQ: make internally used IRQs also honor the pending EOI stack") it was mentioned that both the check_eoi_deferral per-CPU variable and the cpu_has_pending_apic_eoi() were added just to have as little impact on existing behavior as possible, to reduce the risk of a last minute regression in 4.13. Upon closer inspection, dropping the variable is an option only if all callers of ->end() would assume the responsibility of also calling flush_ready_eoi(). Therefore only drop the cpu_has_pending_apic_eoi() guard now. Signed-off-by: Jan Beulich Acked-by: Andrew Cooper --- diff --git a/xen/arch/x86/irq.c b/xen/arch/x86/irq.c index 03e2f8edb6..9adad3ff04 100644 --- a/xen/arch/x86/irq.c +++ b/xen/arch/x86/irq.c @@ -1990,18 +1990,13 @@ void do_IRQ(struct cpu_user_regs *regs) * If higher priority vectors still have their EOIs pending, we may * not issue an EOI here, as this would EOI the highest priority one. */ - if ( cpu_has_pending_apic_eoi() ) - { - this_cpu(check_eoi_deferral) = true; - desc->handler->end(desc, vector); - this_cpu(check_eoi_deferral) = false; - - spin_unlock(&desc->lock); - flush_ready_eoi(); - goto out_no_unlock; - } - + this_cpu(check_eoi_deferral) = true; desc->handler->end(desc, vector); + this_cpu(check_eoi_deferral) = false; + + spin_unlock(&desc->lock); + flush_ready_eoi(); + goto out_no_unlock; } out_no_end: