From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx142.postini.com [74.125.245.142]) by kanga.kvack.org (Postfix) with SMTP id C94436B005C for ; Thu, 19 Jul 2012 03:18:33 -0400 (EDT) Message-ID: <5007B5E4.1010602@cn.fujitsu.com> Date: Thu, 19 Jul 2012 15:23:16 +0800 From: Wen Congyang MIME-Version: 1.0 Subject: Re: [RFC PATCH v4 2/13] memory-hotplug : add physical memory hotplug code to acpi_memory_device_remove References: <50068974.1070409@jp.fujitsu.com> <50068AB9.20005@jp.fujitsu.com> In-Reply-To: <50068AB9.20005@jp.fujitsu.com> Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=ISO-2022-JP Sender: owner-linux-mm@kvack.org List-ID: To: Yasuaki Ishimatsu Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-acpi@vger.kernel.org, rientjes@google.com, liuj97@gmail.com, len.brown@intel.com, benh@kernel.crashing.org, paulus@samba.org, cl@linux.com, minchan.kim@gmail.com, akpm@linux-foundation.org, kosaki.motohiro@jp.fujitsu.com At 07/18/2012 06:06 PM, Yasuaki Ishimatsu Wrote: > acpi_memory_device_remove() has been prepared to remove physical memory. > But, the function only frees acpi_memory_device currentlry. > > The patch adds following functions into acpi_memory_device_remove(): > - offline memory > - remove physical memory. It only check whether memory is online or not. > - free acpi_memory_device > > CC: David Rientjes > CC: Jiang Liu > CC: Len Brown > CC: Benjamin Herrenschmidt > CC: Paul Mackerras > CC: Christoph Lameter > Cc: Minchan Kim > CC: Andrew Morton > CC: KOSAKI Motohiro > CC: Wen Congyang > Signed-off-by: Yasuaki Ishimatsu > > --- > drivers/acpi/acpi_memhotplug.c | 27 ++++++++++++++++++++++++++- > drivers/base/memory.c | 39 +++++++++++++++++++++++++++++++++++++++ > include/linux/memory.h | 5 +++++ > include/linux/memory_hotplug.h | 5 +++++ > mm/memory_hotplug.c | 22 ++++++++++++++++++++++ > 5 files changed, 97 insertions(+), 1 deletion(-) > > Index: linux-3.5-rc6/drivers/acpi/acpi_memhotplug.c > =================================================================== > --- linux-3.5-rc6.orig/drivers/acpi/acpi_memhotplug.c 2012-07-17 11:20:15.117796971 +0900 > +++ linux-3.5-rc6/drivers/acpi/acpi_memhotplug.c 2012-07-17 13:36:30.325594022 +0900 > @@ -29,6 +29,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -452,12 +453,36 @@ static int acpi_memory_device_add(struct > static int acpi_memory_device_remove(struct acpi_device *device, int type) > { > struct acpi_memory_device *mem_device = NULL; > - > + struct acpi_memory_info *info, *tmp; > + int result; > + int node; > > if (!device || !acpi_driver_data(device)) > return -EINVAL; > > mem_device = acpi_driver_data(device); > + > + node = acpi_get_node(mem_device->device->handle); > + list_for_each_entry_safe(info, tmp, &mem_device->res_list, list) { > + if (!info->enabled) > + continue; > + > + if (!is_memblk_offline(info->start_addr, info->length)) { > + result = offline_memory(info->start_addr, info->length); > + if (result) > + return result; > + } > + if (node < 0) > + node = memory_add_physaddr_to_nid(info->start_addr); > + > + result = remove_memory(node, info->start_addr, info->length); > + if (result) > + return result; > + > + list_del(&info->list); > + kfree(info); > + } > + > kfree(mem_device); > > return 0; > Index: linux-3.5-rc6/include/linux/memory_hotplug.h > =================================================================== > --- linux-3.5-rc6.orig/include/linux/memory_hotplug.h 2012-07-17 11:20:15.133796772 +0900 > +++ linux-3.5-rc6/include/linux/memory_hotplug.h 2012-07-17 11:29:41.490716352 +0900 > @@ -221,6 +221,7 @@ static inline void unlock_memory_hotplug > #ifdef CONFIG_MEMORY_HOTREMOVE > > extern int is_mem_section_removable(unsigned long pfn, unsigned long nr_pages); > +extern int remove_memory(int nid, u64 start, u64 size); > > #else > static inline int is_mem_section_removable(unsigned long pfn, > @@ -228,6 +229,10 @@ static inline int is_mem_section_removab > { > return 0; > } > +static inline int remove_memory(int nid, u64 start, u64 size) > +{ > + return -EBUSY; > +} > #endif /* CONFIG_MEMORY_HOTREMOVE */ > > extern int mem_online_node(int nid); > Index: linux-3.5-rc6/mm/memory_hotplug.c > =================================================================== > --- linux-3.5-rc6.orig/mm/memory_hotplug.c 2012-07-17 11:20:15.129796821 +0900 > +++ linux-3.5-rc6/mm/memory_hotplug.c 2012-07-17 13:25:18.952986069 +0900 > @@ -998,6 +998,28 @@ int offline_memory(u64 start, u64 size) > end_pfn = start_pfn + PFN_DOWN(size); > return offline_pages(start_pfn, end_pfn, 120 * HZ); > } > + > +int remove_memory(int nid, u64 start, u64 size) > +{ > + int ret = -EBUSY; > + lock_memory_hotplug(); > + /* > + * The memory might become online by other task, even if you offine it. > + * So we check whether the cpu has been onlined or not. > + */ > + if (!is_memblk_offline(start, size)) { > + pr_warn("memory removing [mem %#010llx-%#010llx] failed, " > + "because the memmory range is online\n", > + start, start + size); > + ret = -EAGAIN; > + } > + > + unlock_memory_hotplug(); > + return ret; > + > +} > +EXPORT_SYMBOL_GPL(remove_memory); > + > #else > int offline_memory(u64 start, u64 size) > { > Index: linux-3.5-rc6/drivers/base/memory.c > =================================================================== > --- linux-3.5-rc6.orig/drivers/base/memory.c 2012-07-17 11:20:15.120796934 +0900 > +++ linux-3.5-rc6/drivers/base/memory.c 2012-07-17 11:20:54.626302995 +0900 > @@ -70,6 +70,45 @@ void unregister_memory_isolate_notifier( > } > EXPORT_SYMBOL(unregister_memory_isolate_notifier); > > +bool is_memblk_offline(unsigned long start, unsigned long size) > +{ > + struct memory_block *mem = NULL; > + struct mem_section *section; > + unsigned long start_pfn, end_pfn; > + unsigned long pfn, section_nr; > + > + start_pfn = PFN_DOWN(start); > + end_pfn = start_pfn + PFN_DOWN(start); This line is wrong. I think you want this: end_pfn = start_pfn + PFN_UP(size); > + > + for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { > + section_nr = pfn_to_section_nr(pfn); > + if (!present_section_nr(section_nr)); The ';' should be removed. Otherwise, this function always return true... Thanks Wen Congyang > + continue; > + > + section = __nr_to_section(section_nr); > + /* same memblock? */ > + if (mem) > + if((section_nr >= mem->start_section_nr) && > + (section_nr <= mem->end_section_nr)) > + continue; > + > + mem = find_memory_block_hinted(section, mem); > + if (!mem) > + continue; > + if (mem->state == MEM_OFFLINE) > + continue; > + > + kobject_put(&mem->dev.kobj); > + return false; > + } > + > + if (mem) > + kobject_put(&mem->dev.kobj); > + > + return true; > +} > +EXPORT_SYMBOL(is_memblk_offline); > + > /* > * register_memory - Setup a sysfs device for a memory block > */ > Index: linux-3.5-rc6/include/linux/memory.h > =================================================================== > --- linux-3.5-rc6.orig/include/linux/memory.h 2012-07-17 11:18:00.693477455 +0900 > +++ linux-3.5-rc6/include/linux/memory.h 2012-07-17 11:20:54.632302919 +0900 > @@ -106,6 +106,10 @@ static inline int memory_isolate_notify( > { > return 0; > } > +static inline bool is_memblk_offline(unsigned long start, unsigned long size) > +{ > + return false; > +} > #else > extern int register_memory_notifier(struct notifier_block *nb); > extern void unregister_memory_notifier(struct notifier_block *nb); > @@ -120,6 +124,7 @@ extern int memory_isolate_notify(unsigne > extern struct memory_block *find_memory_block_hinted(struct mem_section *, > struct memory_block *); > extern struct memory_block *find_memory_block(struct mem_section *); > +extern bool is_memblk_offline(unsigned long start, unsigned long size); > #define CONFIG_MEM_BLOCK_SIZE (PAGES_PER_SECTION< enum mem_add_context { BOOT, HOTPLUG }; > #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */ > > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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