From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from db9outboundpool.messaging.microsoft.com (mail-db9lp0251.outbound.messaging.microsoft.com [213.199.154.251]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id BCD752C00B7 for ; Tue, 7 Jan 2014 16:41:22 +1100 (EST) From: Dongsheng Wang To: , Subject: [PATCH] powerpc/mpic: supply a .disable callback Date: Tue, 7 Jan 2014 13:38:06 +0800 Message-ID: <1389073086-6763-1-git-send-email-dongsheng.wang@freescale.com> MIME-Version: 1.0 Content-Type: text/plain Cc: linuxppc-dev@lists.ozlabs.org, Wang Dongsheng List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Wang Dongsheng Currently MPIC provides .mask, but not .disable. This means that effectively disable_irq() soft-disables the interrupt, and you get a .mask call if an interrupt actually occurs. I'm not sure if this was intended as a performance benefit (it seems common to omit .disable on powerpc interrupt controllers, but nowhere else), but it interacts badly with threaded/workqueue interrupts (including KVM reflection). In such cases, where the real interrupt handler does a disable_irq_nosync(), schedules defered handling, and returns, we get two interrupts for every real interrupt. The second interrupt does nothing but see that IRQ_DISABLED is set, and decide that it would be a good idea to actually call .mask. Signed-off-by: Scott Wood Signed-off-by: Wang Dongsheng diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c index 0e166ed..dd7564b 100644 --- a/arch/powerpc/sysdev/mpic.c +++ b/arch/powerpc/sysdev/mpic.c @@ -975,6 +975,7 @@ void mpic_set_destination(unsigned int virq, unsigned int cpuid) } static struct irq_chip mpic_irq_chip = { + .irq_disable = mpic_mask_irq, .irq_mask = mpic_mask_irq, .irq_unmask = mpic_unmask_irq, .irq_eoi = mpic_end_irq, @@ -984,6 +985,7 @@ static struct irq_chip mpic_irq_chip = { #ifdef CONFIG_SMP static struct irq_chip mpic_ipi_chip = { + .irq_disable = mpic_mask_ipi, .irq_mask = mpic_mask_ipi, .irq_unmask = mpic_unmask_ipi, .irq_eoi = mpic_end_ipi, @@ -991,6 +993,7 @@ static struct irq_chip mpic_ipi_chip = { #endif /* CONFIG_SMP */ static struct irq_chip mpic_tm_chip = { + .irq_disable = mpic_mask_tm, .irq_mask = mpic_mask_tm, .irq_unmask = mpic_unmask_tm, .irq_eoi = mpic_end_irq, @@ -1001,6 +1004,7 @@ static struct irq_chip mpic_tm_chip = { static struct irq_chip mpic_irq_ht_chip = { .irq_startup = mpic_startup_ht_irq, .irq_shutdown = mpic_shutdown_ht_irq, + .irq_disable = mpic_mask_irq, .irq_mask = mpic_mask_irq, .irq_unmask = mpic_unmask_ht_irq, .irq_eoi = mpic_end_ht_irq, -- 1.8.5