From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753450AbdKXKgr (ORCPT ); Fri, 24 Nov 2017 05:36:47 -0500 Received: from szxga05-in.huawei.com ([45.249.212.191]:11024 "EHLO szxga05-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753136AbdKXKgq (ORCPT ); Fri, 24 Nov 2017 05:36:46 -0500 Message-ID: <5A17F5DF.2040108@huawei.com> Date: Fri, 24 Nov 2017 18:35:11 +0800 From: zhong jiang User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0) Gecko/20120428 Thunderbird/12.0.1 MIME-Version: 1.0 To: Andrea Reale CC: , , , , , , , , , , , Subject: Re: [PATCH v2 4/5] mm: memory_hotplug: Add memory hotremove probe device References: <22d34fe30df0fbacbfceeb47e20cb1184af73585.1511433386.git.ar@linux.vnet.ibm.com> In-Reply-To: <22d34fe30df0fbacbfceeb47e20cb1184af73585.1511433386.git.ar@linux.vnet.ibm.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.29.68] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020204.5A17F628.0056,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2014-11-16 11:51:01, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 4b1a08e1d5ac668e1355a794e0db1272 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org HI, Andrea I don't see "memory_add_physaddr_to_nid" in arch/arm64. Am I miss something? Thnaks zhongjiang On 2017/11/23 19:14, Andrea Reale wrote: > Adding a "remove" sysfs handle that can be used to trigger > memory hotremove manually, exactly simmetrically with > what happens with the "probe" device for hot-add. > > This is usueful for architecture that do not rely on > ACPI for memory hot-remove. > > Signed-off-by: Andrea Reale > Signed-off-by: Maciej Bielski > --- > drivers/base/memory.c | 34 +++++++++++++++++++++++++++++++++- > 1 file changed, 33 insertions(+), 1 deletion(-) > > diff --git a/drivers/base/memory.c b/drivers/base/memory.c > index 1d60b58..8ccb67c 100644 > --- a/drivers/base/memory.c > +++ b/drivers/base/memory.c > @@ -530,7 +530,36 @@ memory_probe_store(struct device *dev, struct device_attribute *attr, > } > > static DEVICE_ATTR(probe, S_IWUSR, NULL, memory_probe_store); > -#endif > + > +#ifdef CONFIG_MEMORY_HOTREMOVE > +static ssize_t > +memory_remove_store(struct device *dev, > + struct device_attribute *attr, const char *buf, size_t count) > +{ > + u64 phys_addr; > + int nid, ret; > + unsigned long pages_per_block = PAGES_PER_SECTION * sections_per_block; > + > + ret = kstrtoull(buf, 0, &phys_addr); > + if (ret) > + return ret; > + > + if (phys_addr & ((pages_per_block << PAGE_SHIFT) - 1)) > + return -EINVAL; > + > + nid = memory_add_physaddr_to_nid(phys_addr); > + ret = lock_device_hotplug_sysfs(); > + if (ret) > + return ret; > + > + remove_memory(nid, phys_addr, > + MIN_MEMORY_BLOCK_SIZE * sections_per_block); > + unlock_device_hotplug(); > + return count; > +} > +static DEVICE_ATTR(remove, S_IWUSR, NULL, memory_remove_store); > +#endif /* CONFIG_MEMORY_HOTREMOVE */ > +#endif /* CONFIG_ARCH_MEMORY_PROBE */ > > #ifdef CONFIG_MEMORY_FAILURE > /* > @@ -790,6 +819,9 @@ bool is_memblock_offlined(struct memory_block *mem) > static struct attribute *memory_root_attrs[] = { > #ifdef CONFIG_ARCH_MEMORY_PROBE > &dev_attr_probe.attr, > +#ifdef CONFIG_MEMORY_HOTREMOVE > + &dev_attr_remove.attr, > +#endif > #endif > > #ifdef CONFIG_MEMORY_FAILURE