From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=45228 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1P3nKR-000837-82 for qemu-devel@nongnu.org; Thu, 07 Oct 2010 06:04:01 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1P3nKP-0007pA-PT for qemu-devel@nongnu.org; Thu, 07 Oct 2010 06:03:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:10088) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1P3nKP-0007p4-GB for qemu-devel@nongnu.org; Thu, 07 Oct 2010 06:03:57 -0400 Date: Thu, 7 Oct 2010 11:57:51 +0200 From: "Michael S. Tsirkin" Message-ID: <20101007095751.GA7098@redhat.com> References: <20101006145650.GA10968@redhat.com> <1286383724.3020.8.camel@x201> <20101006170222.GB13486@redhat.com> <1286385864.3020.26.camel@x201> <20101006214440.GA17149@redhat.com> <1286402738.3020.40.camel@x201> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1286402738.3020.40.camel@x201> Subject: [Qemu-devel] Re: [PATCHv2] qemu-kvm/vhost: fix up irqfd support List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alex Williamson Cc: kvm@vger.kernel.org, Juan Quintela , mtosatti@redhat.com, qemu-devel@nongnu.org, avi@redhat.com, Amit Shah On Wed, Oct 06, 2010 at 04:05:38PM -0600, Alex Williamson wrote: > On Wed, 2010-10-06 at 23:44 +0200, Michael S. Tsirkin wrote: > > On Wed, Oct 06, 2010 at 11:24:24AM -0600, Alex Williamson wrote: > > > You could always keep the functions as separate wrapper callers of the > > > common function so you only need to keep true = unset, false = set > > > straight in one place. Thanks, > > > > > > Just to show why it does not work, I did exactly this: as you see the > > code is shorter but the true/false magic gets spread: it was in 2 > > places, (set/unset) now it is in 4 places and it is within the loop, in > > code that is more complex. > > You seem to have missed the wrapper function. I'm simply suggesting > something like this: Good idea. I tweaked the code a bit more and came up with this: I think I will keep this as an incremental patch just to keep diffs small. msix: factor out mask notifier code Move some common code handling msix mask notifiers to a function. Signed-off-by: Michael S. Tsirkin diff --git a/hw/msix.c b/hw/msix.c index 3d4dd61..5f66d20 100644 --- a/hw/msix.c +++ b/hw/msix.c @@ -583,40 +583,26 @@ void msix_unuse_all_vectors(PCIDevice *dev) msix_free_irq_entries(dev); } -static int msix_set_mask_notifier_for_vector(PCIDevice *dev, unsigned vector) +/* Invoke the notifier if vector entry is used and unmasked. */ +static int msix_notify_if_unmasked(PCIDevice *dev, unsigned vector, int masked) { - int r = 0; - if (vector >= dev->msix_entries_nr || !dev->msix_entry_used[vector]) - return 0; - assert(dev->msix_mask_notifier); - - /* Unmask the new notifier unless vector is masked. */ - if (!msix_is_masked(dev, vector)) { - r = dev->msix_mask_notifier(dev, vector, false); - if (r < 0) { - return r; - } + if (!dev->msix_entry_used[vector] || msix_is_masked(dev, vector)) { + return 0; } - return r; + return dev->msix_mask_notifier(dev, vector, masked); } -static int msix_unset_mask_notifier_for_vector(PCIDevice *dev, unsigned vector) +static int msix_set_mask_notifier_for_vector(PCIDevice *dev, unsigned vector) { - int r = 0; - if (vector >= dev->msix_entries_nr || !dev->msix_entry_used[vector]) - return 0; - - assert(dev->msix_mask_notifier); + /* Notifier has been set. Invoke it on unmasked vectors. */ + return msix_notify_if_unmasked(dev, vector, 0); +} - /* Mask the old notifier unless it is already masked. */ - if (!msix_is_masked(dev, vector)) { - r = dev->msix_mask_notifier(dev, vector, true); - if (r < 0) { - return r; - } - } - return r; +static int msix_unset_mask_notifier_for_vector(PCIDevice *dev, unsigned vector) +{ + /* Notifier will be unset. Invoke it to mask unmasked entries. */ + return msix_notify_if_unmasked(dev, vector, 1); } int msix_set_mask_notifier(PCIDevice *dev, msix_mask_notifier_func f)