From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35199) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WiN8N-0007Ot-Hi for qemu-devel@nongnu.org; Thu, 08 May 2014 08:09:13 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WiN8G-00006Q-P0 for qemu-devel@nongnu.org; Thu, 08 May 2014 08:09:07 -0400 Message-ID: <536B73D9.5070300@suse.de> Date: Thu, 08 May 2014 14:08:57 +0200 From: Alexander Graf MIME-Version: 1.0 References: <1399442518-26303-1-git-send-email-aik@ozlabs.ru> <1399442518-26303-2-git-send-email-aik@ozlabs.ru> <536B700E.709@suse.de> In-Reply-To: <536B700E.709@suse.de> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [Qemu-ppc] [PATCH 1/6] xics: add flags for interrupts List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alexey Kardashevskiy Cc: qemu-ppc@nongnu.org, qemu-devel@nongnu.org On 05/08/2014 01:52 PM, Alexander Graf wrote: > On 05/07/2014 08:01 AM, Alexey Kardashevskiy wrote: >> The existing interrupt allocation scheme in SPAPR assumes that >> interrupts are allocated at the start time, continously and the config >> will not change. However, there are cases when this is not going to work >> such as: >> >> 1. migration - we will have to have an ability to choose interrupt >> numbers for devices in the command line and this will create gaps in >> interrupt space. >> >> 2. PCI hotplug - interrupts from unplugged device need to be returned >> back to interrupt pool, otherwise we will quickly run out of interrupts. >> >> This replaces a separate lslsi[] array with a byte in the ICSIRQState >> struct and defines "LSI" and "MSI" flags. Neither of these flags set >> signals that the descriptor is not allocated and not in use. >> >> Signed-off-by: Alexey Kardashevskiy >> --- >> hw/intc/xics.c | 21 ++++++++++++++------- >> hw/intc/xics_kvm.c | 5 ++--- >> include/hw/ppc/xics.h | 5 ++++- >> 3 files changed, 20 insertions(+), 11 deletions(-) >> >> diff --git a/hw/intc/xics.c b/hw/intc/xics.c >> index 64aabe7..1f89a00 100644 >> --- a/hw/intc/xics.c >> +++ b/hw/intc/xics.c >> @@ -438,7 +438,7 @@ static void ics_set_irq(void *opaque, int srcno, >> int val) >> { >> ICSState *ics = (ICSState *)opaque; >> - if (ics->islsi[srcno]) { >> + if (ics->irqs[srcno].flags & XICS_FLAGS_LSI) { >> set_irq_lsi(ics, srcno, val); >> } else { >> set_irq_msi(ics, srcno, val); >> @@ -475,7 +475,7 @@ static void ics_write_xive(ICSState *ics, int nr, >> int server, >> trace_xics_ics_write_xive(nr, srcno, server, priority); >> - if (ics->islsi[srcno]) { >> + if (ics->irqs[srcno].flags & XICS_FLAGS_LSI) { >> write_xive_lsi(ics, srcno); >> } else { >> write_xive_msi(ics, srcno); >> @@ -497,7 +497,7 @@ static void ics_resend(ICSState *ics) >> for (i = 0; i < ics->nr_irqs; i++) { >> /* FIXME: filter by server#? */ >> - if (ics->islsi[i]) { >> + if (ics->irqs[i].flags & XICS_FLAGS_LSI) { >> resend_lsi(ics, i); >> } else { >> resend_msi(ics, i); >> @@ -512,7 +512,7 @@ static void ics_eoi(ICSState *ics, int nr) >> trace_xics_ics_eoi(nr); >> - if (ics->islsi[srcno]) { >> + if (ics->irqs[srcno].flags & XICS_FLAGS_LSI) { >> irq->status &= ~XICS_STATUS_SENT; >> } >> } >> @@ -609,7 +609,6 @@ static void ics_realize(DeviceState *dev, Error >> **errp) >> return; >> } >> ics->irqs = g_malloc0(ics->nr_irqs * sizeof(ICSIRQState)); >> - ics->islsi = g_malloc0(ics->nr_irqs * sizeof(bool)); >> ics->qirqs = qemu_allocate_irqs(ics_set_irq, ics, ics->nr_irqs); >> } >> @@ -646,11 +645,19 @@ qemu_irq xics_get_qirq(XICSState *icp, int irq) >> return icp->ics->qirqs[irq - icp->ics->offset]; >> } >> +static void ics_set_irq_type(ICSState *ics, int srcno, bool lsi) >> +{ >> + ics->irqs[srcno].flags |= >> + lsi ? XICS_FLAGS_LSI : XICS_FLAGS_MSI; >> +} >> + >> void xics_set_irq_type(XICSState *icp, int irq, bool lsi) >> { >> - assert(ics_valid_irq(icp->ics, irq)); >> + ICSState *ics = icp->ics; >> - icp->ics->islsi[irq - icp->ics->offset] = lsi; >> + assert(ics_valid_irq(ics, irq)); >> + >> + ics_set_irq_type(ics, irq - ics->offset, lsi); > > What if this gets called with MSI first, then LSI on the same irq number? Following your code I think this never happens. But to ensure it doesn't add an assert(!(ics->irqs[srcno].flags & XICS_FLAGS_IRQTYPE)) in ircs_set_irq_type() maybe? Alex