From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from song.cn.fujitsu.com (unknown [222.73.24.84]) by ozlabs.org (Postfix) with ESMTP id D7EA52C030A for ; Fri, 13 Jul 2012 13:38:02 +1000 (EST) Message-ID: <4FFF9929.4000100@cn.fujitsu.com> Date: Fri, 13 Jul 2012 11:42:33 +0800 From: Wen Congyang MIME-Version: 1.0 To: Yasuaki Ishimatsu Subject: Re: [RFC PATCH v3 5/13] memory-hotplug : does not release memory region in PAGES_PER_SECTION chunks References: <4FFAB0A2.8070304@jp.fujitsu.com> <4FFAB1F3.1020304@jp.fujitsu.com> In-Reply-To: <4FFAB1F3.1020304@jp.fujitsu.com> Content-Type: text/plain; charset=ISO-2022-JP Cc: len.brown@intel.com, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, paulus@samba.org, minchan.kim@gmail.com, kosaki.motohiro@jp.fujitsu.com, rientjes@google.com, cl@linux.com, linuxppc-dev@lists.ozlabs.org, akpm@linux-foundation.org, liuj97@gmail.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , At 07/09/2012 06:26 PM, Yasuaki Ishimatsu Wrote: > Since applying a patch(de7f0cba96786c), release_mem_region() has been changed > as called in PAGES_PER_SECTION chunks because register_memory_resource() is > called in PAGES_PER_SECTION chunks by add_memory(). But it seems firmware > dependency. If CRS are written in the PAGES_PER_SECTION chunks in ACPI DSDT > Table, register_memory_resource() is called in PAGES_PER_SECTION chunks. > But if CRS are written in the DIMM unit in ACPI DSDT Table, > register_memory_resource() is called in DIMM unit. So release_mem_region() > should not be called in PAGES_PER_SECTION chunks. The patch fixes it. > > 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 | 13 +++++++++---- > mm/memory_hotplug.c | 4 ++-- > 2 files changed, 11 insertions(+), 6 deletions(-) > > Index: linux-3.5-rc4/mm/memory_hotplug.c > =================================================================== > --- linux-3.5-rc4.orig/mm/memory_hotplug.c 2012-07-03 14:22:03.549198802 +0900 > +++ linux-3.5-rc4/mm/memory_hotplug.c 2012-07-03 14:22:05.919169458 +0900 > @@ -358,11 +358,11 @@ int __remove_pages(struct zone *zone, un > BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK); > BUG_ON(nr_pages % PAGES_PER_SECTION); > > + release_mem_region(phys_start_pfn << PAGE_SHIFT, nr_pages * PAGE_SIZE); > + > 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; > - release_mem_region(pfn << PAGE_SHIFT, > - PAGES_PER_SECTION << PAGE_SHIFT); > ret = __remove_section(zone, __pfn_to_section(pfn)); > if (ret) > break; > Index: linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c > =================================================================== > --- linux-3.5-rc4.orig/arch/powerpc/platforms/pseries/hotplug-memory.c 2012-07-03 14:21:45.641422678 > +0900 Hmm, I think you should change your mail client's config. Thanks Wen Congyang > +++ linux-3.5-rc4/arch/powerpc/platforms/pseries/hotplug-memory.c 2012-07-03 14:22:05.920169437 +0900 > @@ -77,7 +77,8 @@ static int pseries_remove_memblock(unsig > { > unsigned long start, start_pfn; > struct zone *zone; > - int ret; > + int i, ret; > + int sections_to_remove; > > start_pfn = base >> PAGE_SHIFT; > > @@ -97,9 +98,13 @@ static int pseries_remove_memblock(unsig > * to sysfs "state" file and we can't remove sysfs entries > * while writing to it. So we have to defer it to here. > */ > - ret = __remove_pages(zone, start_pfn, memblock_size >> PAGE_SHIFT); > - if (ret) > - return ret; > + 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); > + if (ret) > + return ret; > + } > > /* > * Update memory regions for memory remove > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ >