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Mon, 1 Jul 2019 14:23:32 +0000 Received: from SL2P216MB0187.KORP216.PROD.OUTLOOK.COM ([fe80::9d2d:391f:5f49:c806]) by SL2P216MB0187.KORP216.PROD.OUTLOOK.COM ([fe80::9d2d:391f:5f49:c806%6]) with mapi id 15.20.2032.019; Mon, 1 Jul 2019 14:23:32 +0000 From: Nicholas Johnson To: "linux-kernel@vger.kernel.org" CC: "linux-pci@vger.kernel.org" , "bhelgaas@google.com" , "mika.westerberg@linux.intel.com" , "corbet@lwn.net" , "benh@kernel.crashing.org" , "logang@deltatee.com" Subject: [PATCH v7 2/8] PCI: Skip resource distribution when no hotplug bridges Thread-Topic: [PATCH v7 2/8] PCI: Skip resource distribution when no hotplug bridges Thread-Index: AQHVMBiP5bDg6T7Bu0SPG+HDJyh4Cw== Date: Mon, 1 Jul 2019 14:23:32 +0000 Message-ID: Accept-Language: en-AU, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-clientproxiedby: SYBPR01CA0182.ausprd01.prod.outlook.com (2603:10c6:10:52::26) To SL2P216MB0187.KORP216.PROD.OUTLOOK.COM (2603:1096:100:22::19) x-incomingtopheadermarker: OriginalChecksum:7E4747C3D9BF8D3B8D4313F0B691BF67281AFE05A8C03827655A689AE334C134;UpperCasedChecksum:9E143170F26BA325A71C9F50700EB9153257DCE0AAF7BA0944A9B49B30E053F5;SizeAsReceived:7696;Count:47 x-ms-exchange-messagesentrepresentingtype: 1 x-tmn: [QNw58P8eezGIQg1bREdWRCZcMV+0/IjsjvUvREBKuWdRTNv/ODR0hNWoMttjATb64hXHXluKyfg=] x-microsoft-original-message-id: <20190701142316.GA5201@nicholas-usb> x-ms-publictraffictype: Email x-incomingheadercount: 47 x-eopattributedmessage: 0 x-microsoft-antispam: BCL:0;PCL:0;RULEID:(2390118)(5050001)(7020095)(20181119110)(201702061078)(5061506573)(5061507331)(1603103135)(2017031320274)(2017031322404)(2017031323274)(2017031324274)(1601125500)(1603101475)(1701031045);SRVR:PU1APC01HT089; x-ms-traffictypediagnostic: PU1APC01HT089: x-microsoft-antispam-message-info: YuQZyMB/0v1jQQihjQLw6sHpnD8+3F50hZtAfGQendM2yXCxgnjRXH8GL+29tzKhgxQEC20Q/EnEG8gT8F755DWeJVHklqFH8GbA9IyhVBnai+gSZ3vtF+iNkFKhgHYURVoH3Lfnj0ssdBZNaMXLbkyynElUn8zjRmgFhtwtvmCJTbDMIdYKDXup/iwjS+We Content-ID: <7E2897BBBFD585449B559074D51FAD9A@KORP216.PROD.OUTLOOK.COM> MIME-Version: 1.0 X-OriginatorOrg: outlook.com X-MS-Exchange-CrossTenant-RMS-PersistedConsumerOrg: 00000000-0000-0000-0000-000000000000 X-MS-Exchange-CrossTenant-Network-Message-Id: a3b34ab7-6744-4208-039f-08d6fe2fb1d7 X-MS-Exchange-CrossTenant-rms-persistedconsumerorg: 00000000-0000-0000-0000-000000000000 X-MS-Exchange-CrossTenant-originalarrivaltime: 01 Jul 2019 14:23:32.3292 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Internet X-MS-Exchange-CrossTenant-id: 84df9e7f-e9f6-40af-b435-aaaaaaaaaaaa X-MS-Exchange-Transport-CrossTenantHeadersStamped: PU1APC01HT089 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP If "hotplug_bridges == 0", "!dev->is_hotplug_bridge" is always true, so the loop that divides the remaining resources among hotplug-capable bridges does nothing. Check for "hotplug_bridges == 0" earlier, so we don't even have to compute the amount of remaining resources. No functional change intended. Signed-off-by: Nicholas Johnson --- drivers/pci/setup-bus.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index af28af898..04adeebe8 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -1887,6 +1887,9 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus, return; } + if (hotplug_bridges == 0) + return; + /* * Calculate the total amount of extra resource space we can * pass to bridges below this one. This is basically the @@ -1936,8 +1939,6 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus, * Distribute available extra resources equally between * hotplug-capable downstream ports taking alignment into * account. - * - * Here hotplug_bridges is always != 0. */ align = pci_resource_alignment(bridge, io_res); io = div64_ul(available_io, hotplug_bridges);