From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f199.google.com (mail-pf0-f199.google.com [209.85.192.199]) by kanga.kvack.org (Postfix) with ESMTP id A53506B0033 for ; Fri, 24 Nov 2017 05:36:48 -0500 (EST) Received: by mail-pf0-f199.google.com with SMTP id k84so11627277pfj.18 for ; Fri, 24 Nov 2017 02:36:48 -0800 (PST) Received: from szxga05-in.huawei.com (szxga05-in.huawei.com. [45.249.212.191]) by mx.google.com with ESMTPS id w24si17767311plq.427.2017.11.24.02.36.46 for (version=TLS1 cipher=AES128-SHA bits=128/128); Fri, 24 Nov 2017 02:36:47 -0800 (PST) Message-ID: <5A17F5DF.2040108@huawei.com> Date: Fri, 24 Nov 2017 18:35:11 +0800 From: zhong jiang MIME-Version: 1.0 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 Sender: owner-linux-mm@kvack.org List-ID: To: Andrea Reale Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, m.bielski@virtualopensystems.com, arunks@qti.qualcomm.com, mark.rutland@arm.com, scott.branden@broadcom.com, will.deacon@arm.com, qiuxishi@huawei.com, catalin.marinas@arm.com, mhocko@suse.com, realean2@ie.ibm.com 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 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org