From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932190Ab2GBDBq (ORCPT ); Sun, 1 Jul 2012 23:01:46 -0400 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:36247 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754798Ab2GBDBn (ORCPT ); Sun, 1 Jul 2012 23:01:43 -0400 X-SecurityPolicyCheck: OK by SHieldMailChecker v1.7.4 Message-ID: <4FF10EFF.5050803@jp.fujitsu.com> Date: Mon, 2 Jul 2012 12:01:19 +0900 From: Yasuaki Ishimatsu User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:13.0) Gecko/20120614 Thunderbird/13.0.1 MIME-Version: 1.0 To: Jiang Liu CC: , , , , , , , , , , , Subject: Re: [RFC PATCH 10/12] memory-hotplug : free memmap of sparse-vmemmap References: <4FEA9C88.1070800@jp.fujitsu.com> <4FEAA09F.5000907@jp.fujitsu.com> <4FEF2214.4000205@gmail.com> In-Reply-To: <4FEF2214.4000205@gmail.com> Content-Type: text/plain; charset="ISO-2022-JP" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jiang, 2012/07/01 0:58, Jiang Liu wrote: > On 06/27/2012 01:56 PM, Yasuaki Ishimatsu wrote: >> I don't think that all pages of virtual mapping in removed memory can be >> freed, since page which type is MIX_SECTION_INFO is difficult to free. >> So, the patch only frees page which type is SECTION_INFO at first. >> >> 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/x86/mm/init_64.c | 89 ++++++++++++++++++++++++++++++++++++++++++++++++++ >> include/linux/mm.h | 2 + >> mm/memory_hotplug.c | 5 ++ >> mm/sparse.c | 5 +- >> 4 files changed, 99 insertions(+), 2 deletions(-) >> >> Index: linux-3.5-rc4/include/linux/mm.h >> =================================================================== >> --- linux-3.5-rc4.orig/include/linux/mm.h 2012-06-27 09:11:13.790150442 +0900 >> +++ linux-3.5-rc4/include/linux/mm.h 2012-06-27 09:11:16.433117400 +0900 >> @@ -1588,6 +1588,8 @@ int vmemmap_populate(struct page *start_ >> void vmemmap_populate_print_last(void); >> void register_page_bootmem_memmap(unsigned long section_nr, struct page *map, >> unsigned long size); >> +void vmemmap_kfree(struct page *memmpa, unsigned long nr_pages); >> +void vmemmap_free_bootmem(struct page *memmpa, unsigned long nr_pages); >> >> enum mf_flags { >> MF_COUNT_INCREASED = 1 << 0, >> Index: linux-3.5-rc4/mm/sparse.c >> =================================================================== >> --- linux-3.5-rc4.orig/mm/sparse.c 2012-06-27 09:06:35.317631878 +0900 >> +++ linux-3.5-rc4/mm/sparse.c 2012-06-27 09:11:16.434117388 +0900 >> @@ -614,12 +614,13 @@ static inline struct page *kmalloc_secti >> /* This will make the necessary allocations eventually. */ >> return sparse_mem_map_populate(pnum, nid); >> } >> -static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages) >> +static void __kfree_section_memmap(struct page *page, unsigned long nr_pages) >> { >> - return; /* XXX: Not implemented yet */ >> + vmemmap_kfree(page, nr_pages); >> } >> static void free_map_bootmem(struct page *page, unsigned long nr_pages) >> { >> + vmemmap_free_bootmem(page, nr_pages); >> } >> #else >> static struct page *__kmalloc_section_memmap(unsigned long nr_pages) >> Index: linux-3.5-rc4/arch/x86/mm/init_64.c >> =================================================================== >> --- linux-3.5-rc4.orig/arch/x86/mm/init_64.c 2012-06-27 09:11:13.791150430 +0900 >> +++ linux-3.5-rc4/arch/x86/mm/init_64.c 2012-06-27 09:11:59.254581998 +0900 >> @@ -978,6 +978,95 @@ vmemmap_populate(struct page *start_page >> return 0; >> } >> >> +unsigned long find_and_clear_pte_page(unsigned long addr, unsigned long end, >> + struct page *page) > I think the third parameter should be "struct page **pp" instead of "struct page *page". > And "page = pte_page(*pte)" should be "*pp = pte_page(*pte)". > Otherwise the found page pointer can't be returned to the caller and vmemmap_kfree() > just sees random value in variable "page". Oh, you are right. I'll update it. Thanks, Yasuaki Ishimatsu >> +{ >> + pgd_t *pgd; >> + pud_t *pud; >> + pmd_t *pmd; >> + pte_t *pte; >> + unsigned long next; >> + >> + page = NULL; >> + >> + pgd = pgd_offset_k(addr); >> + if (pgd_none(*pgd)) >> + return PAGE_SIZE; >> + >> + pud = pud_offset(pgd, addr); >> + if (pud_none(*pud)) >> + return PAGE_SIZE; >> + >> + if (!cpu_has_pse) { >> + next = (addr + PAGE_SIZE) & PAGE_MASK; >> + pmd = pmd_offset(pud, addr); >> + if (pmd_none(*pmd)) >> + return next; >> + >> + pte = pte_offset_kernel(pmd, addr); >> + if (pte_none(*pte)) >> + return next; >> + >> + page = pte_page(*pte); >> + pte_clear(&init_mm, addr, pte); >> + } else { >> + next = pmd_addr_end(addr, end); >> + >> + pmd = pmd_offset(pud, addr); >> + if (pmd_none(*pmd)) >> + return next; >> + >> + page = pmd_page(*pmd); >> + pmd_clear(pmd); >> + } >> + >> + return next; >> +} >> + >> +void __meminit >> +vmemmap_kfree(struct page *memmap, unsigned long nr_pages) >> +{ >> + unsigned long addr = (unsigned long)memmap; >> + unsigned long end = (unsigned long)(memmap + nr_pages); >> + unsigned long next; >> + unsigned int order; >> + struct page *page; >> + >> + for (; addr < end; addr = next) { >> + next = find_and_clear_pte_page(addr, end, page); >> + if (!page) >> + continue; >> + >> + if (is_vmalloc_addr(page)) >> + vfree(page); >> + else { >> + order = next - addr; >> + free_pages((unsigned long)page, >> + get_order(sizeof(struct page) * order)); >> + } >> + } >> +} >> + >> +void __meminit >> +vmemmap_free_bootmem(struct page *memmap, unsigned long nr_pages) >> +{ >> + unsigned long addr = (unsigned long)memmap; >> + unsigned long end = (unsigned long)(memmap + nr_pages); >> + unsigned long next; >> + struct page *page; >> + unsigned long magic; >> + >> + for (; addr < end; addr = next) { >> + next = find_and_clear_pte_page(addr, end, page); >> + if (!page) >> + continue; >> + >> + magic = (unsigned long) page->lru.next; >> + if (magic == SECTION_INFO) >> + put_page_bootmem(page); >> + } >> +} >> + >> void __meminit >> register_page_bootmem_memmap(unsigned long section_nr, struct page *start_page, >> unsigned long size) >> Index: linux-3.5-rc4/mm/memory_hotplug.c >> =================================================================== >> --- linux-3.5-rc4.orig/mm/memory_hotplug.c 2012-06-27 09:11:13.789150454 +0900 >> +++ linux-3.5-rc4/mm/memory_hotplug.c 2012-06-27 09:11:16.436117363 +0900 >> @@ -303,6 +303,8 @@ static int __meminit __add_section(int n >> #ifdef CONFIG_SPARSEMEM_VMEMMAP >> static int __remove_section(struct zone *zone, struct mem_section *ms) >> { >> + unsigned long flags; >> + struct pglist_data *pgdat = zone->zone_pgdat; >> int ret; >> >> if (!valid_section(ms)) >> @@ -310,6 +312,9 @@ static int __remove_section(struct zone >> >> ret = unregister_memory_section(ms); >> >> + pgdat_resize_lock(pgdat, &flags); >> + sparse_remove_one_section(zone, ms); >> + pgdat_resize_unlock(pgdat, &flags); >> return ret; >> } >> #else >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-acpi" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > > > -- > 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 >