From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx155.postini.com [74.125.245.155]) by kanga.kvack.org (Postfix) with SMTP id 48D676B005C for ; Thu, 19 Jul 2012 04:32:24 -0400 (EDT) Received: by wgbdt14 with SMTP id dt14so1986706wgb.26 for ; Thu, 19 Jul 2012 01:32:22 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <50068BF4.1080603@jp.fujitsu.com> References: <50068974.1070409@jp.fujitsu.com> <50068BF4.1080603@jp.fujitsu.com> Date: Thu, 19 Jul 2012 16:32:22 +0800 Message-ID: Subject: Re: [RFC PATCH v4 7/13] memory-hotplug : remove_memory calls __remove_pages From: Bob Liu Content-Type: text/plain; charset=UTF-8 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, wency@cn.fujitsu.com On Wed, Jul 18, 2012 at 6:12 PM, Yasuaki Ishimatsu wrote: > The patch adds __remove_pages() to remove_memory(). Then the range of > phys_start_pfn argument and nr_pages argument in __remove_pagse() may > have different zone. So zone argument is removed from __remove_pages() > and __remove_pages() caluculates zone in each section. > > When CONFIG_SPARSEMEM_VMEMMAP is defined, there is no way to remove a memmap. > So __remove_section only calls unregister_memory_section(). > > 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 > > --- > arch/powerpc/platforms/pseries/hotplug-memory.c | 5 +---- > include/linux/memory_hotplug.h | 3 +-- > mm/memory_hotplug.c | 19 ++++++++++++------- > 3 files changed, 14 insertions(+), 13 deletions(-) > > Index: linux-3.5-rc6/mm/memory_hotplug.c > =================================================================== > --- linux-3.5-rc6.orig/mm/memory_hotplug.c 2012-07-18 18:00:27.440145432 +0900 > +++ linux-3.5-rc6/mm/memory_hotplug.c 2012-07-18 18:01:02.070712487 +0900 > @@ -275,11 +275,14 @@ static int __meminit __add_section(int n > #ifdef CONFIG_SPARSEMEM_VMEMMAP > static int __remove_section(struct zone *zone, struct mem_section *ms) > { > - /* > - * XXX: Freeing memmap with vmemmap is not implement yet. > - * This should be removed later. > - */ > - return -EBUSY; > + int ret = -EINVAL; > + > + if (!valid_section(ms)) > + return ret; > + > + ret = unregister_memory_section(ms); > + I saw a patch from Jiang Liu "mm/hotplug: free zone->pageset when a zone becomes empty" to free the zone->pageset and i think there may more cleanup needed when a zone becomes empty. We already have __add_zone() in __add_section(), what about add a function like __remove_zone() to do the cleanup here? > + return ret; > } > #else > static int __remove_section(struct zone *zone, struct mem_section *ms) > @@ -346,11 +349,11 @@ EXPORT_SYMBOL_GPL(__add_pages); > * sure that pages are marked reserved and zones are adjust properly by > * calling offline_pages(). > */ > -int __remove_pages(struct zone *zone, unsigned long phys_start_pfn, > - unsigned long nr_pages) > +int __remove_pages(unsigned long phys_start_pfn, unsigned long nr_pages) > { > unsigned long i, ret = 0; > int sections_to_remove; > + struct zone *zone; > > /* > * We can only remove entire sections > @@ -363,6 +366,7 @@ int __remove_pages(struct zone *zone, un > sections_to_remove = nr_pages / PAGES_PER_SECTION; > for (i = 0; i < sections_to_remove; i++) { > unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION; > + zone = page_zone(pfn_to_page(pfn)); > ret = __remove_section(zone, __pfn_to_section(pfn)); > if (ret) > break; > @@ -1031,6 +1035,7 @@ int __ref remove_memory(int nid, u64 sta > /* remove memmap entry */ > firmware_map_remove(start, start + size, "System RAM"); > > + __remove_pages(start >> PAGE_SHIFT, size >> PAGE_SHIFT); > out: > unlock_memory_hotplug(); > return ret; > Index: linux-3.5-rc6/include/linux/memory_hotplug.h > =================================================================== > --- linux-3.5-rc6.orig/include/linux/memory_hotplug.h 2012-07-18 18:00:27.445145371 +0900 > +++ linux-3.5-rc6/include/linux/memory_hotplug.h 2012-07-18 18:00:40.461982690 +0900 > @@ -89,8 +89,7 @@ extern bool is_pageblock_removable_noloc > /* reasonably generic interface to expand the physical pages in a zone */ > extern int __add_pages(int nid, struct zone *zone, unsigned long start_pfn, > unsigned long nr_pages); > -extern int __remove_pages(struct zone *zone, unsigned long start_pfn, > - unsigned long nr_pages); > +extern int __remove_pages(unsigned long start_pfn, unsigned long nr_pages); > > #ifdef CONFIG_NUMA > extern int memory_add_physaddr_to_nid(u64 start); > Index: linux-3.5-rc6/arch/powerpc/platforms/pseries/hotplug-memory.c > =================================================================== > --- linux-3.5-rc6.orig/arch/powerpc/platforms/pseries/hotplug-memory.c 2012-07-18 18:00:27.442145407 +0900 > +++ linux-3.5-rc6/arch/powerpc/platforms/pseries/hotplug-memory.c 2012-07-18 18:00:40.470982578 +0900 > @@ -76,7 +76,6 @@ unsigned long memory_block_size_bytes(vo > static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size) > { > unsigned long start, start_pfn; > - struct zone *zone; > int i, ret; > int sections_to_remove; > > @@ -87,8 +86,6 @@ static int pseries_remove_memblock(unsig > return 0; > } > > - zone = page_zone(pfn_to_page(start_pfn)); > - > /* > * Remove section mappings and sysfs entries for the > * section of the memory we are removing. > @@ -101,7 +98,7 @@ static int pseries_remove_memblock(unsig > sections_to_remove = (memblock_size >> PAGE_SHIFT) / PAGES_PER_SECTION; > for (i = 0; i < sections_to_remove; i++) { > unsigned long pfn = start_pfn + i * PAGES_PER_SECTION; > - ret = __remove_pages(zone, start_pfn, PAGES_PER_SECTION); > + ret = __remove_pages(start_pfn, PAGES_PER_SECTION); > if (ret) > return ret; > } > > -- > 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 -- Regards, --Bob -- 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