From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40635) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Wn1yr-0008JR-37 for qemu-devel@nongnu.org; Wed, 21 May 2014 04:34:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Wn1yk-0002ew-PZ for qemu-devel@nongnu.org; Wed, 21 May 2014 04:34:33 -0400 Message-ID: <537C6511.6080403@suse.de> Date: Wed, 21 May 2014 10:34:25 +0200 From: Alexander Graf MIME-Version: 1.0 References: <1400147999-4793-1-git-send-email-aik@ozlabs.ru> <1400147999-4793-5-git-send-email-aik@ozlabs.ru> In-Reply-To: <1400147999-4793-5-git-send-email-aik@ozlabs.ru> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2 4/8] spapr: Move interrupt allocator to xics List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alexey Kardashevskiy , qemu-devel@nongnu.org Cc: qemu-ppc@nongnu.org On 15.05.14 11:59, Alexey Kardashevskiy wrote: > The current allocator returns IRQ numbers from a pool and does not > support IRQs reuse in any form as it did not keep track of what it > previously returned, it only keeps the last returned IRQ. Some use > cases such as PCI hot(un)plug may require IRQ release and reallocation. > > This moves an allocator from SPAPR to XICS. > > This switches IRQ users to use new API. > > This uses LSI/MSI flags to know if interrupt is allocated. > > The interrupt release function will be posted as a separate patch. > > Signed-off-by: Alexey Kardashevskiy > --- > hw/intc/xics.c | 88 ++++++++++++++++++++++++++++++++++++++++++++++++++ > hw/ppc/spapr.c | 67 -------------------------------------- > hw/ppc/spapr_events.c | 2 +- > hw/ppc/spapr_pci.c | 6 ++-- > hw/ppc/spapr_vio.c | 2 +- > include/hw/ppc/spapr.h | 10 ------ > include/hw/ppc/xics.h | 2 ++ > trace-events | 4 +++ > 8 files changed, 99 insertions(+), 82 deletions(-) > > diff --git a/hw/intc/xics.c b/hw/intc/xics.c > index 83a809e..fdcbb3a 100644 > --- a/hw/intc/xics.c > +++ b/hw/intc/xics.c > @@ -689,6 +689,94 @@ void xics_set_irq_type(XICSState *icp, int irq, bool lsi) > ics_set_irq_type(ics, irq - ics->offset, lsi); > } > > +#define ICS_IRQ_FREE(ics, srcno) \ > + (!((ics)->irqs[(srcno)].flags & (XICS_FLAGS_IRQ_MASK))) > + > +static int ics_find_free_block(ICSState *ics, int num, int alignnum) > +{ > + int first, i; > + > + for (first = 0; first < ics->nr_irqs; first += alignnum) { > + if (num > (ics->nr_irqs - first)) { > + return -1; > + } > + for (i = first; i < first + num; ++i) { > + if (!ICS_IRQ_FREE(ics, i)) { > + break; > + } > + } > + if (i == (first + num)) { > + return first; > + } > + } > + > + return -1; > +} > + > +int xics_alloc(XICSState *icp, int src, int irq_hint, bool lsi) > +{ > + ICSState *ics = &icp->ics[src]; > + int irq; > + > + if (irq_hint) { > + assert(src == xics_find_source(icp, irq_hint)); Could this ever get triggered by a guest? Why don't we just fail as if the IRQ wasn't available? Alex