From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Tue, 24 Apr 2018 18:05:58 -0500 From: Bjorn Helgaas To: Mika Westerberg Cc: Bjorn Helgaas , "Rafael J. Wysocki" , Len Brown , Mario.Limonciello@dell.com, Michael Jamet , Yehezkel Bernat , Andy Shevchenko , Lukas Wunner , linux-pci@vger.kernel.org, linux-acpi@vger.kernel.org Subject: Re: [PATCH v5 6/9] PCI: Move resource distribution for a single bridge outside of the loop Message-ID: <20180424230558.GA101734@bhelgaas-glaptop.roam.corp.google.com> References: <20180416103453.46232-1-mika.westerberg@linux.intel.com> <20180416103453.46232-7-mika.westerberg@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20180416103453.46232-7-mika.westerberg@linux.intel.com> Sender: linux-acpi-owner@vger.kernel.org List-ID: On Mon, Apr 16, 2018 at 01:34:50PM +0300, Mika Westerberg wrote: > There is a special case where there is only single bridge on the bus. In > that case we just assign all resources to it. Currently this is done as > a part of the resource distribution loop but it does not have to be > there, and moving it outside actually improves readability. > > While there we can add hotplug_bridges == 1 && normal_bridges == 0 to > the same block because they are dealt the same way. > > Suggested-by: Bjorn Helgaas > Signed-off-by: Mika Westerberg > Reviewed-by: Rafael J. Wysocki > --- > drivers/pci/setup-bus.c | 28 +++++++++++++++++----------- > 1 file changed, 17 insertions(+), 11 deletions(-) > > diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c > index eb3059fb7f63..a1b63c7745d0 100644 > --- a/drivers/pci/setup-bus.c > +++ b/drivers/pci/setup-bus.c > @@ -1947,6 +1947,22 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus, > mmio_start = mmio_res->start; > mmio_pref_start = mmio_pref_res->start; > > + /* > + * There is only one bridge on the bus so it gets all available > + * resources which it can then distribute to the possible > + * hotplug bridges below. > + */ > + if ((hotplug_bridges == 0 && normal_bridges == 1) || > + (hotplug_bridges == 1 && normal_bridges == 0)) { if (hotplug_bridges + normal_bridges == 1) { Don't repost just for this; I can fold it in if you agree. > + dev = list_first_entry(&bus->devices, struct pci_dev, bus_list); > + if (dev->subordinate) { > + pci_bus_distribute_available_resources(dev->subordinate, > + add_list, available_io, available_mmio, > + available_mmio_pref); > + } > + return; > + } > + > /* > * Go over devices on this bus and distribute the remaining > * resource space between hotplug bridges. > @@ -1959,17 +1975,7 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus, > if (!b) > continue; > > - if (!hotplug_bridges && normal_bridges == 1) { > - /* > - * There is only one bridge on the bus (upstream > - * port) so it gets all available resources > - * which it can then distribute to the possible > - * hotplug bridges below. > - */ > - pci_bus_distribute_available_resources(b, add_list, > - available_io, available_mmio, > - available_mmio_pref); > - } else if (dev->is_hotplug_bridge) { > + if (dev->is_hotplug_bridge) { > resource_size_t io, mmio, mmio_pref; > > /* > -- > 2.16.3 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-acpi" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html