From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl1-f198.google.com (mail-pl1-f198.google.com [209.85.214.198]) by kanga.kvack.org (Postfix) with ESMTP id 0DF848E0001 for ; Mon, 10 Sep 2018 19:44:04 -0400 (EDT) Received: by mail-pl1-f198.google.com with SMTP id 2-v6so10572786plc.11 for ; Mon, 10 Sep 2018 16:44:04 -0700 (PDT) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id u9-v6sor3090814plz.78.2018.09.10.16.44.02 for (Google Transport Security); Mon, 10 Sep 2018 16:44:02 -0700 (PDT) Subject: [PATCH 4/4] nvdimm: Trigger the device probe on a cpu local to the device From: Alexander Duyck Date: Mon, 10 Sep 2018 16:44:00 -0700 Message-ID: <20180910234400.4068.15541.stgit@localhost.localdomain> In-Reply-To: <20180910232615.4068.29155.stgit@localhost.localdomain> References: <20180910232615.4068.29155.stgit@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-nvdimm@lists.01.org Cc: pavel.tatashin@microsoft.com, mhocko@suse.com, dave.jiang@intel.com, mingo@kernel.org, dave.hansen@intel.com, jglisse@redhat.com, akpm@linux-foundation.org, logang@deltatee.com, dan.j.williams@intel.com, kirill.shutemov@linux.intel.com From: Alexander Duyck This patch is based off of the pci_call_probe function used to initialize PCI devices. The general idea here is to move the probe call to a location that is local to the memory being initialized. By doing this we can shave significant time off of the total time needed for initialization. With this patch applied I see a significant reduction in overall init time as without it the init varied between 23 and 37 seconds to initialize a 3GB node. With this patch applied the variance is only between 23 and 26 seconds to initialize each node. I hope to refine this further in the future by combining this logic into the async_schedule_domain code that is already in use. By doing that it would likely make this functionality redundant. Signed-off-by: Alexander Duyck --- drivers/nvdimm/bus.c | 45 ++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 44 insertions(+), 1 deletion(-) diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c index 8aae6dcc839f..5b73953176b1 100644 --- a/drivers/nvdimm/bus.c +++ b/drivers/nvdimm/bus.c @@ -27,6 +27,7 @@ #include #include #include +#include #include "nd-core.h" #include "nd.h" #include "pfn.h" @@ -90,6 +91,48 @@ static void nvdimm_bus_probe_end(struct nvdimm_bus *nvdimm_bus) nvdimm_bus_unlock(&nvdimm_bus->dev); } +struct nvdimm_drv_dev { + struct nd_device_driver *nd_drv; + struct device *dev; +}; + +static long __nvdimm_call_probe(void *_nddd) +{ + struct nvdimm_drv_dev *nddd = _nddd; + struct nd_device_driver *nd_drv = nddd->nd_drv; + + return nd_drv->probe(nddd->dev); +} + +static int nvdimm_call_probe(struct nd_device_driver *nd_drv, + struct device *dev) +{ + struct nvdimm_drv_dev nddd = { nd_drv, dev }; + int rc, node, cpu; + + /* + * Execute driver initialization on node where the device is + * attached. This way the driver will be able to access local + * memory instead of having to initialize memory across nodes. + */ + node = dev_to_node(dev); + + cpu_hotplug_disable(); + + if (node < 0 || node >= MAX_NUMNODES || !node_online(node)) + cpu = nr_cpu_ids; + else + cpu = cpumask_any_and(cpumask_of_node(node), cpu_online_mask); + + if (cpu < nr_cpu_ids) + rc = work_on_cpu(cpu, __nvdimm_call_probe, &nddd); + else + rc = __nvdimm_call_probe(&nddd); + + cpu_hotplug_enable(); + return rc; +} + static int nvdimm_bus_probe(struct device *dev) { struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver); @@ -104,7 +147,7 @@ static int nvdimm_bus_probe(struct device *dev) dev->driver->name, dev_name(dev)); nvdimm_bus_probe_start(nvdimm_bus); - rc = nd_drv->probe(dev); + rc = nvdimm_call_probe(nd_drv, dev); if (rc == 0) nd_region_probe_success(nvdimm_bus, dev); else