| Message ID | 50126E2F.8010301@cn.fujitsu.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
On Fri, Jul 27, 2012 at 06:32:15PM +0800, Wen Congyang wrote: > We don't call __add_pages() directly in the function add_memory() > because some other architecture related things need to be done > before or after calling __add_pages(). So we should introduce > a new function arch_remove_memory() to revert the things > done in arch_add_memory(). > > Note: the function for s390 is not implemented(I don't know how to > implement it for s390). There is no hardware or firmware interface which could trigger a hot memory remove on s390. So there is nothing that needs to be implemented.
At 07/30/2012 06:23 PM, Heiko Carstens Wrote: > On Fri, Jul 27, 2012 at 06:32:15PM +0800, Wen Congyang wrote: >> We don't call __add_pages() directly in the function add_memory() >> because some other architecture related things need to be done >> before or after calling __add_pages(). So we should introduce >> a new function arch_remove_memory() to revert the things >> done in arch_add_memory(). >> >> Note: the function for s390 is not implemented(I don't know how to >> implement it for s390). > > There is no hardware or firmware interface which could trigger a > hot memory remove on s390. So there is nothing that needs to be > implemented. Thanks for providing this information. According to this, arch_remove_memory() for s390 can just return -EBUSY. Thanks Wen Congyang > > -- > 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 >
On Mon, 30 Jul 2012 18:35:37 +0800 Wen Congyang <wency@cn.fujitsu.com> wrote: > At 07/30/2012 06:23 PM, Heiko Carstens Wrote: > > On Fri, Jul 27, 2012 at 06:32:15PM +0800, Wen Congyang wrote: > >> We don't call __add_pages() directly in the function add_memory() > >> because some other architecture related things need to be done > >> before or after calling __add_pages(). So we should introduce > >> a new function arch_remove_memory() to revert the things > >> done in arch_add_memory(). > >> > >> Note: the function for s390 is not implemented(I don't know how to > >> implement it for s390). > > > > There is no hardware or firmware interface which could trigger a > > hot memory remove on s390. So there is nothing that needs to be > > implemented. > > Thanks for providing this information. > > According to this, arch_remove_memory() for s390 can just return > -EBUSY. Yes, but there is a prototype mismatch for arch_remove_memory() on s390 and also other architectures (u64 vs. unsigned long). arch/s390/mm/init.c:262: error: conflicting types for ‘arch_remove_memory’ include/linux/memory_hotplug.h:88: error: previous declaration of ‘arch_remove_memory’ was here In memory_hotplug.h you have: extern int arch_remove_memory(unsigned long start, unsigned long size); On all archs other than x86 you have: int arch_remove_memory(u64 start, u64 size)
At 07/31/2012 08:40 PM, Gerald Schaefer Wrote: > On Mon, 30 Jul 2012 18:35:37 +0800 > Wen Congyang <wency@cn.fujitsu.com> wrote: > >> At 07/30/2012 06:23 PM, Heiko Carstens Wrote: >>> On Fri, Jul 27, 2012 at 06:32:15PM +0800, Wen Congyang wrote: >>>> We don't call __add_pages() directly in the function add_memory() >>>> because some other architecture related things need to be done >>>> before or after calling __add_pages(). So we should introduce >>>> a new function arch_remove_memory() to revert the things >>>> done in arch_add_memory(). >>>> >>>> Note: the function for s390 is not implemented(I don't know how to >>>> implement it for s390). >>> >>> There is no hardware or firmware interface which could trigger a >>> hot memory remove on s390. So there is nothing that needs to be >>> implemented. >> >> Thanks for providing this information. >> >> According to this, arch_remove_memory() for s390 can just return >> -EBUSY. > > Yes, but there is a prototype mismatch for arch_remove_memory() on s390 > and also other architectures (u64 vs. unsigned long). > > arch/s390/mm/init.c:262: error: conflicting types for > ‘arch_remove_memory’ include/linux/memory_hotplug.h:88: error: previous > declaration of ‘arch_remove_memory’ was here > > In memory_hotplug.h you have: > extern int arch_remove_memory(unsigned long start, unsigned long size); > > On all archs other than x86 you have: > int arch_remove_memory(u64 start, u64 size) Thanks for pointing it out. I will fix it. Wen Congyang > > -- > 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/ >
2012/7/27 Wen Congyang <wency@cn.fujitsu.com>: > We don't call __add_pages() directly in the function add_memory() > because some other architecture related things need to be done > before or after calling __add_pages(). So we should introduce > a new function arch_remove_memory() to revert the things > done in arch_add_memory(). > > Note: the function for s390 is not implemented(I don't know how to > implement it for s390). > > CC: David Rientjes <rientjes@google.com> > CC: Jiang Liu <liuj97@gmail.com> > CC: Len Brown <len.brown@intel.com> > CC: Benjamin Herrenschmidt <benh@kernel.crashing.org> > CC: Paul Mackerras <paulus@samba.org> > CC: Christoph Lameter <cl@linux.com> > Cc: Minchan Kim <minchan.kim@gmail.com> > CC: Andrew Morton <akpm@linux-foundation.org> > CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> > CC: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> > Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> > --- > arch/ia64/mm/init.c | 16 ++++ > arch/powerpc/mm/mem.c | 14 +++ > arch/s390/mm/init.c | 8 ++ > arch/sh/mm/init.c | 15 +++ > arch/tile/mm/init.c | 8 ++ > arch/x86/include/asm/pgtable_types.h | 1 + > arch/x86/mm/init_32.c | 10 ++ > arch/x86/mm/init_64.c | 160 ++++++++++++++++++++++++++++++++++ > arch/x86/mm/pageattr.c | 47 +++++----- > include/linux/memory_hotplug.h | 1 + > mm/memory_hotplug.c | 1 + > 11 files changed, 259 insertions(+), 22 deletions(-) > > diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c > index 0eab454..1e345ed 100644 > --- a/arch/ia64/mm/init.c > +++ b/arch/ia64/mm/init.c > @@ -688,6 +688,22 @@ int arch_add_memory(int nid, u64 start, u64 size) > > return ret; > } > + > +#ifdef CONFIG_MEMORY_HOTREMOVE > +int arch_remove_memory(u64 start, u64 size) > +{ > + unsigned long start_pfn = start >> PAGE_SHIFT; > + unsigned long nr_pages = size >> PAGE_SHIFT; > + int ret; > + > + ret = __remove_pages(start_pfn, nr_pages); > + if (ret) > + pr_warn("%s: Problem encountered in __remove_pages() as" > + " ret=%d\n", __func__, ret); > + > + return ret; > +} > +#endif > #endif > in 3.5 ia64 implementation did not call __remove_pages at all. so why? > /* > diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c > index baaafde..249cef4 100644 > --- a/arch/powerpc/mm/mem.c > +++ b/arch/powerpc/mm/mem.c > @@ -133,6 +133,20 @@ int arch_add_memory(int nid, u64 start, u64 size) > > return __add_pages(nid, zone, start_pfn, nr_pages); > } > + > +#ifdef CONFIG_MEMORY_HOTREMOVE > +int arch_remove_memory(u64 start, u64 size) > +{ > + unsigned long start_pfn = start >> PAGE_SHIFT; > + unsigned long nr_pages = size >> PAGE_SHIFT; > + > + start = (unsigned long)__va(start); > + if (remove_section_mapping(start, start + size)) > + return -EINVAL; > + > + return __remove_pages(start_pfn, nr_pages); > +} > +#endif > #endif /* CONFIG_MEMORY_HOTPLUG */ > > /* > diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c > index 6adbc08..ca4bc46 100644 > --- a/arch/s390/mm/init.c > +++ b/arch/s390/mm/init.c > @@ -257,4 +257,12 @@ int arch_add_memory(int nid, u64 start, u64 size) > vmem_remove_mapping(start, size); > return rc; > } > + > +#ifdef CONFIG_MEMORY_HOTREMOVE > +int arch_remove_memory(u64 start, u64 size) > +{ > + /* TODO */ > + return -EBUSY; > +} > +#endif > #endif /* CONFIG_MEMORY_HOTPLUG */ > diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c > index 82cc576..fc84491 100644 > --- a/arch/sh/mm/init.c > +++ b/arch/sh/mm/init.c > @@ -558,4 +558,19 @@ int memory_add_physaddr_to_nid(u64 addr) > EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); > #endif > > +#ifdef CONFIG_MEMORY_HOTREMOVE > +int arch_remove_memory(u64 start, u64 size) > +{ > + unsigned long start_pfn = start >> PAGE_SHIFT; > + unsigned long nr_pages = size >> PAGE_SHIFT; > + int ret; > + > + ret = __remove_pages(start_pfn, nr_pages); > + if (unlikely(ret)) > + pr_warn("%s: Failed, __remove_pages() == %d\n", __func__, > + ret); > + > + return ret; > +} > +#endif > #endif /* CONFIG_MEMORY_HOTPLUG */ > diff --git a/arch/tile/mm/init.c b/arch/tile/mm/init.c > index ef29d6c..2749515 100644 > --- a/arch/tile/mm/init.c > +++ b/arch/tile/mm/init.c > @@ -935,6 +935,14 @@ int remove_memory(u64 start, u64 size) > { > return -EINVAL; > } > + > +#ifdef CONFIG_MEMORY_HOTREMOVE > +int arch_remove_memory(u64 start, u64 size) > +{ > + /* TODO */ > + return -EBUSY; > +} > +#endif > #endif > > struct kmem_cache *pgd_cache; > diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h > index 013286a..b725af2 100644 > --- a/arch/x86/include/asm/pgtable_types.h > +++ b/arch/x86/include/asm/pgtable_types.h > @@ -334,6 +334,7 @@ static inline void update_page_count(int level, unsigned long pages) { } > * as a pte too. > */ > extern pte_t *lookup_address(unsigned long address, unsigned int *level); > +extern int __split_large_page(pte_t *kpte, unsigned long address, pte_t *pbase); > > #endif /* !__ASSEMBLY__ */ > > diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c > index 575d86f..a690153 100644 > --- a/arch/x86/mm/init_32.c > +++ b/arch/x86/mm/init_32.c > @@ -842,6 +842,16 @@ int arch_add_memory(int nid, u64 start, u64 size) > > return __add_pages(nid, zone, start_pfn, nr_pages); > } > + > +#ifdef CONFIG_MEMORY_HOTREMOVE > +int arch_remove_memory(unsigned long start, unsigned long size) > +{ > + unsigned long start_pfn = start >> PAGE_SHIFT; > + unsigned long nr_pages = size >> PAGE_SHIFT; > + > + return __remove_pages(start_pfn, nr_pages); > +} > +#endif > #endif > > /* > diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c > index 2b6b4a3..f1554a9 100644 > --- a/arch/x86/mm/init_64.c > +++ b/arch/x86/mm/init_64.c > @@ -675,6 +675,166 @@ int arch_add_memory(int nid, u64 start, u64 size) > } > EXPORT_SYMBOL_GPL(arch_add_memory); > > +static void __meminit > +phys_pte_remove(pte_t *pte_page, unsigned long addr, unsigned long end) > +{ > + unsigned pages = 0; > + int i = pte_index(addr); > + > + pte_t *pte = pte_page + pte_index(addr); > + > + for (; i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) { > + > + if (addr >= end) > + break; > + > + if (!pte_present(*pte)) > + continue; > + > + pages++; > + set_pte(pte, __pte(0)); > + } > + > + update_page_count(PG_LEVEL_4K, -pages); > +} > + > +static void __meminit > +phys_pmd_remove(pmd_t *pmd_page, unsigned long addr, unsigned long end) > +{ > + unsigned long pages = 0, next; > + int i = pmd_index(addr); > + > + for (; i < PTRS_PER_PMD; i++, addr = next) { > + unsigned long pte_phys; > + pmd_t *pmd = pmd_page + pmd_index(addr); > + pte_t *pte; > + > + if (addr >= end) > + break; > + > + next = (addr & PMD_MASK) + PMD_SIZE; > + > + if (!pmd_present(*pmd)) > + continue; > + > + if (pmd_large(*pmd)) { > + if ((addr & ~PMD_MASK) == 0 && next <= end) { > + set_pmd(pmd, __pmd(0)); > + pages++; > + continue; > + } > + > + /* > + * We use 2M page, but we need to remove part of them, > + * so split 2M page to 4K page. > + */ > + pte = alloc_low_page(&pte_phys); > + __split_large_page((pte_t *)pmd, addr, pte); > + > + spin_lock(&init_mm.page_table_lock); > + pmd_populate_kernel(&init_mm, pmd, __va(pte_phys)); > + spin_unlock(&init_mm.page_table_lock); > + } > + > + spin_lock(&init_mm.page_table_lock); > + pte = map_low_page((pte_t *)pmd_page_vaddr(*pmd)); > + phys_pte_remove(pte, addr, end); > + unmap_low_page(pte); > + spin_unlock(&init_mm.page_table_lock); > + } > + update_page_count(PG_LEVEL_2M, -pages); > +} > + > +static void __meminit > +phys_pud_remove(pud_t *pud_page, unsigned long addr, unsigned long end) > +{ > + unsigned long pages = 0, next; > + int i = pud_index(addr); > + > + for (; i < PTRS_PER_PUD; i++, addr = next) { > + unsigned long pmd_phys; > + pud_t *pud = pud_page + pud_index(addr); > + pmd_t *pmd; > + > + if (addr >= end) > + break; > + > + next = (addr & PUD_MASK) + PUD_SIZE; > + > + if (!pud_present(*pud)) > + continue; > + > + if (pud_large(*pud)) { > + if ((addr & ~PUD_MASK) == 0 && next <= end) { > + set_pud(pud, __pud(0)); > + pages++; > + continue; > + } > + > + /* > + * We use 1G page, but we need to remove part of them, > + * so split 1G page to 2M page. > + */ > + pmd = alloc_low_page(&pmd_phys); > + __split_large_page((pte_t *)pud, addr, (pte_t *)pmd); > + > + spin_lock(&init_mm.page_table_lock); > + pud_populate(&init_mm, pud, __va(pmd_phys)); > + spin_unlock(&init_mm.page_table_lock); > + } > + > + pmd = map_low_page(pmd_offset(pud, 0)); > + phys_pmd_remove(pmd, addr, end); > + unmap_low_page(pmd); > + __flush_tlb_all(); > + } > + __flush_tlb_all(); > + > + update_page_count(PG_LEVEL_1G, -pages); > +} > + > +void __meminit > +kernel_physical_mapping_remove(unsigned long start, unsigned long end) > +{ > + unsigned long next; > + > + start = (unsigned long)__va(start); > + end = (unsigned long)__va(end); > + > + for (; start < end; start = next) { > + pgd_t *pgd = pgd_offset_k(start); > + pud_t *pud; > + > + next = (start + PGDIR_SIZE) & PGDIR_MASK; > + if (next > end) > + next = end; > + > + if (!pgd_present(*pgd)) > + continue; > + > + pud = map_low_page((pud_t *)pgd_page_vaddr(*pgd)); > + phys_pud_remove(pud, __pa(start), __pa(end)); > + unmap_low_page(pud); > + } > + > + __flush_tlb_all(); > +} > + > +#ifdef CONFIG_MEMORY_HOTREMOVE > +int __ref arch_remove_memory(unsigned long start, unsigned long size) > +{ > + unsigned long start_pfn = start >> PAGE_SHIFT; > + unsigned long nr_pages = size >> PAGE_SHIFT; > + int ret; > + > + ret = __remove_pages(start_pfn, nr_pages); > + WARN_ON_ONCE(ret); > + > + kernel_physical_mapping_remove(start, start + size); > + > + return ret; > +} > +#endif > #endif /* CONFIG_MEMORY_HOTPLUG */ > > static struct kcore_list kcore_vsyscall; > diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c > index 931930a..c22963d 100644 > --- a/arch/x86/mm/pageattr.c > +++ b/arch/x86/mm/pageattr.c > @@ -501,21 +501,13 @@ out_unlock: > return do_split; > } > > -static int split_large_page(pte_t *kpte, unsigned long address) > +int __split_large_page(pte_t *kpte, unsigned long address, pte_t *pbase) > { > unsigned long pfn, pfninc = 1; > unsigned int i, level; > - pte_t *pbase, *tmp; > + pte_t *tmp; > pgprot_t ref_prot; > - struct page *base; > - > - if (!debug_pagealloc) > - spin_unlock(&cpa_lock); > - base = alloc_pages(GFP_KERNEL | __GFP_NOTRACK, 0); > - if (!debug_pagealloc) > - spin_lock(&cpa_lock); > - if (!base) > - return -ENOMEM; > + struct page *base = virt_to_page(pbase); > > spin_lock(&pgd_lock); > /* > @@ -523,10 +515,11 @@ static int split_large_page(pte_t *kpte, unsigned long address) > * up for us already: > */ > tmp = lookup_address(address, &level); > - if (tmp != kpte) > - goto out_unlock; > + if (tmp != kpte) { > + spin_unlock(&pgd_lock); > + return 1; > + } > > - pbase = (pte_t *)page_address(base); > paravirt_alloc_pte(&init_mm, page_to_pfn(base)); > ref_prot = pte_pgprot(pte_clrhuge(*kpte)); > /* > @@ -579,17 +572,27 @@ static int split_large_page(pte_t *kpte, unsigned long address) > * going on. > */ > __flush_tlb_all(); > + spin_unlock(&pgd_lock); > > - base = NULL; > + return 0; > +} > > -out_unlock: > - /* > - * If we dropped out via the lookup_address check under > - * pgd_lock then stick the page back into the pool: > - */ > - if (base) > +static int split_large_page(pte_t *kpte, unsigned long address) > +{ > + pte_t *pbase; > + struct page *base; > + > + if (!debug_pagealloc) > + spin_unlock(&cpa_lock); > + base = alloc_pages(GFP_KERNEL | __GFP_NOTRACK, 0); > + if (!debug_pagealloc) > + spin_lock(&cpa_lock); > + if (!base) > + return -ENOMEM; > + > + pbase = (pte_t *)page_address(base); > + if (__split_large_page(kpte, address, pbase)) > __free_page(base); > - spin_unlock(&pgd_lock); > > return 0; > } > diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h > index 8bf820d..0d500be 100644 > --- a/include/linux/memory_hotplug.h > +++ b/include/linux/memory_hotplug.h > @@ -85,6 +85,7 @@ extern void __online_page_free(struct page *page); > > #ifdef CONFIG_MEMORY_HOTREMOVE > extern bool is_pageblock_removable_nolock(struct page *page); > +extern int arch_remove_memory(unsigned long start, unsigned long size); > #endif /* CONFIG_MEMORY_HOTREMOVE */ > > /* reasonably generic interface to expand the physical pages in a zone */ > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index a9e1579..0c932e1 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -1071,6 +1071,7 @@ int __ref remove_memory(int nid, u64 start, u64 size) line 1071? which version does this patch base on? thanks a lot. > /* remove memmap entry */ > firmware_map_remove(start, start + size, "System RAM"); > > + arch_remove_memory(start, size); > out: > unlock_memory_hotplug(); > return ret; > -- > 1.7.1 > > -- > 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/
At 08/01/2012 10:44 AM, jencce zhou Wrote: > 2012/7/27 Wen Congyang <wency@cn.fujitsu.com>: >> We don't call __add_pages() directly in the function add_memory() >> because some other architecture related things need to be done >> before or after calling __add_pages(). So we should introduce >> a new function arch_remove_memory() to revert the things >> done in arch_add_memory(). >> >> Note: the function for s390 is not implemented(I don't know how to >> implement it for s390). >> >> CC: David Rientjes <rientjes@google.com> >> CC: Jiang Liu <liuj97@gmail.com> >> CC: Len Brown <len.brown@intel.com> >> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org> >> CC: Paul Mackerras <paulus@samba.org> >> CC: Christoph Lameter <cl@linux.com> >> Cc: Minchan Kim <minchan.kim@gmail.com> >> CC: Andrew Morton <akpm@linux-foundation.org> >> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> >> CC: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> >> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> >> --- >> arch/ia64/mm/init.c | 16 ++++ >> arch/powerpc/mm/mem.c | 14 +++ >> arch/s390/mm/init.c | 8 ++ >> arch/sh/mm/init.c | 15 +++ >> arch/tile/mm/init.c | 8 ++ >> arch/x86/include/asm/pgtable_types.h | 1 + >> arch/x86/mm/init_32.c | 10 ++ >> arch/x86/mm/init_64.c | 160 ++++++++++++++++++++++++++++++++++ >> arch/x86/mm/pageattr.c | 47 +++++----- >> include/linux/memory_hotplug.h | 1 + >> mm/memory_hotplug.c | 1 + >> 11 files changed, 259 insertions(+), 22 deletions(-) >> >> diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c >> index 0eab454..1e345ed 100644 >> --- a/arch/ia64/mm/init.c >> +++ b/arch/ia64/mm/init.c >> @@ -688,6 +688,22 @@ int arch_add_memory(int nid, u64 start, u64 size) >> >> return ret; >> } >> + >> +#ifdef CONFIG_MEMORY_HOTREMOVE >> +int arch_remove_memory(u64 start, u64 size) >> +{ >> + unsigned long start_pfn = start >> PAGE_SHIFT; >> + unsigned long nr_pages = size >> PAGE_SHIFT; >> + int ret; >> + >> + ret = __remove_pages(start_pfn, nr_pages); >> + if (ret) >> + pr_warn("%s: Problem encountered in __remove_pages() as" >> + " ret=%d\n", __func__, ret); >> + >> + return ret; >> +} >> +#endif >> #endif >> > > in 3.5 ia64 implementation did not call __remove_pages at all. so why? This function only reverts the things done in arch_add_memory(), and it will be called when a memory device is removed. When adding a memory device, __add_pages() is called in arch_add_memory(), so call __remove_pages() in arch_remove_memory(). Thanks Wen Congyang > > >> /* >> diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c >> index baaafde..249cef4 100644 >> --- a/arch/powerpc/mm/mem.c >> +++ b/arch/powerpc/mm/mem.c >> @@ -133,6 +133,20 @@ int arch_add_memory(int nid, u64 start, u64 size) >> >> return __add_pages(nid, zone, start_pfn, nr_pages); >> } >> + >> +#ifdef CONFIG_MEMORY_HOTREMOVE >> +int arch_remove_memory(u64 start, u64 size) >> +{ >> + unsigned long start_pfn = start >> PAGE_SHIFT; >> + unsigned long nr_pages = size >> PAGE_SHIFT; >> + >> + start = (unsigned long)__va(start); >> + if (remove_section_mapping(start, start + size)) >> + return -EINVAL; >> + >> + return __remove_pages(start_pfn, nr_pages); >> +} >> +#endif >> #endif /* CONFIG_MEMORY_HOTPLUG */ >> >> /* >> diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c >> index 6adbc08..ca4bc46 100644 >> --- a/arch/s390/mm/init.c >> +++ b/arch/s390/mm/init.c >> @@ -257,4 +257,12 @@ int arch_add_memory(int nid, u64 start, u64 size) >> vmem_remove_mapping(start, size); >> return rc; >> } >> + >> +#ifdef CONFIG_MEMORY_HOTREMOVE >> +int arch_remove_memory(u64 start, u64 size) >> +{ >> + /* TODO */ >> + return -EBUSY; >> +} >> +#endif >> #endif /* CONFIG_MEMORY_HOTPLUG */ >> diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c >> index 82cc576..fc84491 100644 >> --- a/arch/sh/mm/init.c >> +++ b/arch/sh/mm/init.c >> @@ -558,4 +558,19 @@ int memory_add_physaddr_to_nid(u64 addr) >> EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); >> #endif >> >> +#ifdef CONFIG_MEMORY_HOTREMOVE >> +int arch_remove_memory(u64 start, u64 size) >> +{ >> + unsigned long start_pfn = start >> PAGE_SHIFT; >> + unsigned long nr_pages = size >> PAGE_SHIFT; >> + int ret; >> + >> + ret = __remove_pages(start_pfn, nr_pages); >> + if (unlikely(ret)) >> + pr_warn("%s: Failed, __remove_pages() == %d\n", __func__, >> + ret); >> + >> + return ret; >> +} >> +#endif >> #endif /* CONFIG_MEMORY_HOTPLUG */ >> diff --git a/arch/tile/mm/init.c b/arch/tile/mm/init.c >> index ef29d6c..2749515 100644 >> --- a/arch/tile/mm/init.c >> +++ b/arch/tile/mm/init.c >> @@ -935,6 +935,14 @@ int remove_memory(u64 start, u64 size) >> { >> return -EINVAL; >> } >> + >> +#ifdef CONFIG_MEMORY_HOTREMOVE >> +int arch_remove_memory(u64 start, u64 size) >> +{ >> + /* TODO */ >> + return -EBUSY; >> +} >> +#endif >> #endif >> >> struct kmem_cache *pgd_cache; >> diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h >> index 013286a..b725af2 100644 >> --- a/arch/x86/include/asm/pgtable_types.h >> +++ b/arch/x86/include/asm/pgtable_types.h >> @@ -334,6 +334,7 @@ static inline void update_page_count(int level, unsigned long pages) { } >> * as a pte too. >> */ >> extern pte_t *lookup_address(unsigned long address, unsigned int *level); >> +extern int __split_large_page(pte_t *kpte, unsigned long address, pte_t *pbase); >> >> #endif /* !__ASSEMBLY__ */ >> >> diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c >> index 575d86f..a690153 100644 >> --- a/arch/x86/mm/init_32.c >> +++ b/arch/x86/mm/init_32.c >> @@ -842,6 +842,16 @@ int arch_add_memory(int nid, u64 start, u64 size) >> >> return __add_pages(nid, zone, start_pfn, nr_pages); >> } >> + >> +#ifdef CONFIG_MEMORY_HOTREMOVE >> +int arch_remove_memory(unsigned long start, unsigned long size) >> +{ >> + unsigned long start_pfn = start >> PAGE_SHIFT; >> + unsigned long nr_pages = size >> PAGE_SHIFT; >> + >> + return __remove_pages(start_pfn, nr_pages); >> +} >> +#endif >> #endif >> >> /* >> diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c >> index 2b6b4a3..f1554a9 100644 >> --- a/arch/x86/mm/init_64.c >> +++ b/arch/x86/mm/init_64.c >> @@ -675,6 +675,166 @@ int arch_add_memory(int nid, u64 start, u64 size) >> } >> EXPORT_SYMBOL_GPL(arch_add_memory); >> >> +static void __meminit >> +phys_pte_remove(pte_t *pte_page, unsigned long addr, unsigned long end) >> +{ >> + unsigned pages = 0; >> + int i = pte_index(addr); >> + >> + pte_t *pte = pte_page + pte_index(addr); >> + >> + for (; i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) { >> + >> + if (addr >= end) >> + break; >> + >> + if (!pte_present(*pte)) >> + continue; >> + >> + pages++; >> + set_pte(pte, __pte(0)); >> + } >> + >> + update_page_count(PG_LEVEL_4K, -pages); >> +} >> + >> +static void __meminit >> +phys_pmd_remove(pmd_t *pmd_page, unsigned long addr, unsigned long end) >> +{ >> + unsigned long pages = 0, next; >> + int i = pmd_index(addr); >> + >> + for (; i < PTRS_PER_PMD; i++, addr = next) { >> + unsigned long pte_phys; >> + pmd_t *pmd = pmd_page + pmd_index(addr); >> + pte_t *pte; >> + >> + if (addr >= end) >> + break; >> + >> + next = (addr & PMD_MASK) + PMD_SIZE; >> + >> + if (!pmd_present(*pmd)) >> + continue; >> + >> + if (pmd_large(*pmd)) { >> + if ((addr & ~PMD_MASK) == 0 && next <= end) { >> + set_pmd(pmd, __pmd(0)); >> + pages++; >> + continue; >> + } >> + >> + /* >> + * We use 2M page, but we need to remove part of them, >> + * so split 2M page to 4K page. >> + */ >> + pte = alloc_low_page(&pte_phys); >> + __split_large_page((pte_t *)pmd, addr, pte); >> + >> + spin_lock(&init_mm.page_table_lock); >> + pmd_populate_kernel(&init_mm, pmd, __va(pte_phys)); >> + spin_unlock(&init_mm.page_table_lock); >> + } >> + >> + spin_lock(&init_mm.page_table_lock); >> + pte = map_low_page((pte_t *)pmd_page_vaddr(*pmd)); >> + phys_pte_remove(pte, addr, end); >> + unmap_low_page(pte); >> + spin_unlock(&init_mm.page_table_lock); >> + } >> + update_page_count(PG_LEVEL_2M, -pages); >> +} >> + >> +static void __meminit >> +phys_pud_remove(pud_t *pud_page, unsigned long addr, unsigned long end) >> +{ >> + unsigned long pages = 0, next; >> + int i = pud_index(addr); >> + >> + for (; i < PTRS_PER_PUD; i++, addr = next) { >> + unsigned long pmd_phys; >> + pud_t *pud = pud_page + pud_index(addr); >> + pmd_t *pmd; >> + >> + if (addr >= end) >> + break; >> + >> + next = (addr & PUD_MASK) + PUD_SIZE; >> + >> + if (!pud_present(*pud)) >> + continue; >> + >> + if (pud_large(*pud)) { >> + if ((addr & ~PUD_MASK) == 0 && next <= end) { >> + set_pud(pud, __pud(0)); >> + pages++; >> + continue; >> + } >> + >> + /* >> + * We use 1G page, but we need to remove part of them, >> + * so split 1G page to 2M page. >> + */ >> + pmd = alloc_low_page(&pmd_phys); >> + __split_large_page((pte_t *)pud, addr, (pte_t *)pmd); >> + >> + spin_lock(&init_mm.page_table_lock); >> + pud_populate(&init_mm, pud, __va(pmd_phys)); >> + spin_unlock(&init_mm.page_table_lock); >> + } >> + >> + pmd = map_low_page(pmd_offset(pud, 0)); >> + phys_pmd_remove(pmd, addr, end); >> + unmap_low_page(pmd); >> + __flush_tlb_all(); >> + } >> + __flush_tlb_all(); >> + >> + update_page_count(PG_LEVEL_1G, -pages); >> +} >> + >> +void __meminit >> +kernel_physical_mapping_remove(unsigned long start, unsigned long end) >> +{ >> + unsigned long next; >> + >> + start = (unsigned long)__va(start); >> + end = (unsigned long)__va(end); >> + >> + for (; start < end; start = next) { >> + pgd_t *pgd = pgd_offset_k(start); >> + pud_t *pud; >> + >> + next = (start + PGDIR_SIZE) & PGDIR_MASK; >> + if (next > end) >> + next = end; >> + >> + if (!pgd_present(*pgd)) >> + continue; >> + >> + pud = map_low_page((pud_t *)pgd_page_vaddr(*pgd)); >> + phys_pud_remove(pud, __pa(start), __pa(end)); >> + unmap_low_page(pud); >> + } >> + >> + __flush_tlb_all(); >> +} >> + >> +#ifdef CONFIG_MEMORY_HOTREMOVE >> +int __ref arch_remove_memory(unsigned long start, unsigned long size) >> +{ >> + unsigned long start_pfn = start >> PAGE_SHIFT; >> + unsigned long nr_pages = size >> PAGE_SHIFT; >> + int ret; >> + >> + ret = __remove_pages(start_pfn, nr_pages); >> + WARN_ON_ONCE(ret); >> + >> + kernel_physical_mapping_remove(start, start + size); >> + >> + return ret; >> +} >> +#endif >> #endif /* CONFIG_MEMORY_HOTPLUG */ >> >> static struct kcore_list kcore_vsyscall; >> diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c >> index 931930a..c22963d 100644 >> --- a/arch/x86/mm/pageattr.c >> +++ b/arch/x86/mm/pageattr.c >> @@ -501,21 +501,13 @@ out_unlock: >> return do_split; >> } >> >> -static int split_large_page(pte_t *kpte, unsigned long address) >> +int __split_large_page(pte_t *kpte, unsigned long address, pte_t *pbase) >> { >> unsigned long pfn, pfninc = 1; >> unsigned int i, level; >> - pte_t *pbase, *tmp; >> + pte_t *tmp; >> pgprot_t ref_prot; >> - struct page *base; >> - >> - if (!debug_pagealloc) >> - spin_unlock(&cpa_lock); >> - base = alloc_pages(GFP_KERNEL | __GFP_NOTRACK, 0); >> - if (!debug_pagealloc) >> - spin_lock(&cpa_lock); >> - if (!base) >> - return -ENOMEM; >> + struct page *base = virt_to_page(pbase); >> >> spin_lock(&pgd_lock); >> /* >> @@ -523,10 +515,11 @@ static int split_large_page(pte_t *kpte, unsigned long address) >> * up for us already: >> */ >> tmp = lookup_address(address, &level); >> - if (tmp != kpte) >> - goto out_unlock; >> + if (tmp != kpte) { >> + spin_unlock(&pgd_lock); >> + return 1; >> + } >> >> - pbase = (pte_t *)page_address(base); >> paravirt_alloc_pte(&init_mm, page_to_pfn(base)); >> ref_prot = pte_pgprot(pte_clrhuge(*kpte)); >> /* >> @@ -579,17 +572,27 @@ static int split_large_page(pte_t *kpte, unsigned long address) >> * going on. >> */ >> __flush_tlb_all(); >> + spin_unlock(&pgd_lock); >> >> - base = NULL; >> + return 0; >> +} >> >> -out_unlock: >> - /* >> - * If we dropped out via the lookup_address check under >> - * pgd_lock then stick the page back into the pool: >> - */ >> - if (base) >> +static int split_large_page(pte_t *kpte, unsigned long address) >> +{ >> + pte_t *pbase; >> + struct page *base; >> + >> + if (!debug_pagealloc) >> + spin_unlock(&cpa_lock); >> + base = alloc_pages(GFP_KERNEL | __GFP_NOTRACK, 0); >> + if (!debug_pagealloc) >> + spin_lock(&cpa_lock); >> + if (!base) >> + return -ENOMEM; >> + >> + pbase = (pte_t *)page_address(base); >> + if (__split_large_page(kpte, address, pbase)) >> __free_page(base); >> - spin_unlock(&pgd_lock); >> >> return 0; >> } >> diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h >> index 8bf820d..0d500be 100644 >> --- a/include/linux/memory_hotplug.h >> +++ b/include/linux/memory_hotplug.h >> @@ -85,6 +85,7 @@ extern void __online_page_free(struct page *page); >> >> #ifdef CONFIG_MEMORY_HOTREMOVE >> extern bool is_pageblock_removable_nolock(struct page *page); >> +extern int arch_remove_memory(unsigned long start, unsigned long size); >> #endif /* CONFIG_MEMORY_HOTREMOVE */ >> >> /* reasonably generic interface to expand the physical pages in a zone */ >> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c >> index a9e1579..0c932e1 100644 >> --- a/mm/memory_hotplug.c >> +++ b/mm/memory_hotplug.c >> @@ -1071,6 +1071,7 @@ int __ref remove_memory(int nid, u64 start, u64 size) > > line 1071? which version does this patch base on? thanks a lot. > > >> /* remove memmap entry */ >> firmware_map_remove(start, start + size, "System RAM"); >> >> + arch_remove_memory(start, size); >> out: >> unlock_memory_hotplug(); >> return ret; >> -- >> 1.7.1 >> >> -- >> 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/ >
diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c index 0eab454..1e345ed 100644 --- a/arch/ia64/mm/init.c +++ b/arch/ia64/mm/init.c @@ -688,6 +688,22 @@ int arch_add_memory(int nid, u64 start, u64 size) return ret; } + +#ifdef CONFIG_MEMORY_HOTREMOVE +int arch_remove_memory(u64 start, u64 size) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + int ret; + + ret = __remove_pages(start_pfn, nr_pages); + if (ret) + pr_warn("%s: Problem encountered in __remove_pages() as" + " ret=%d\n", __func__, ret); + + return ret; +} +#endif #endif /* diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index baaafde..249cef4 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -133,6 +133,20 @@ int arch_add_memory(int nid, u64 start, u64 size) return __add_pages(nid, zone, start_pfn, nr_pages); } + +#ifdef CONFIG_MEMORY_HOTREMOVE +int arch_remove_memory(u64 start, u64 size) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + + start = (unsigned long)__va(start); + if (remove_section_mapping(start, start + size)) + return -EINVAL; + + return __remove_pages(start_pfn, nr_pages); +} +#endif #endif /* CONFIG_MEMORY_HOTPLUG */ /* diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index 6adbc08..ca4bc46 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -257,4 +257,12 @@ int arch_add_memory(int nid, u64 start, u64 size) vmem_remove_mapping(start, size); return rc; } + +#ifdef CONFIG_MEMORY_HOTREMOVE +int arch_remove_memory(u64 start, u64 size) +{ + /* TODO */ + return -EBUSY; +} +#endif #endif /* CONFIG_MEMORY_HOTPLUG */ diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c index 82cc576..fc84491 100644 --- a/arch/sh/mm/init.c +++ b/arch/sh/mm/init.c @@ -558,4 +558,19 @@ int memory_add_physaddr_to_nid(u64 addr) EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); #endif +#ifdef CONFIG_MEMORY_HOTREMOVE +int arch_remove_memory(u64 start, u64 size) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + int ret; + + ret = __remove_pages(start_pfn, nr_pages); + if (unlikely(ret)) + pr_warn("%s: Failed, __remove_pages() == %d\n", __func__, + ret); + + return ret; +} +#endif #endif /* CONFIG_MEMORY_HOTPLUG */ diff --git a/arch/tile/mm/init.c b/arch/tile/mm/init.c index ef29d6c..2749515 100644 --- a/arch/tile/mm/init.c +++ b/arch/tile/mm/init.c @@ -935,6 +935,14 @@ int remove_memory(u64 start, u64 size) { return -EINVAL; } + +#ifdef CONFIG_MEMORY_HOTREMOVE +int arch_remove_memory(u64 start, u64 size) +{ + /* TODO */ + return -EBUSY; +} +#endif #endif struct kmem_cache *pgd_cache; diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index 013286a..b725af2 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -334,6 +334,7 @@ static inline void update_page_count(int level, unsigned long pages) { } * as a pte too. */ extern pte_t *lookup_address(unsigned long address, unsigned int *level); +extern int __split_large_page(pte_t *kpte, unsigned long address, pte_t *pbase); #endif /* !__ASSEMBLY__ */ diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index 575d86f..a690153 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -842,6 +842,16 @@ int arch_add_memory(int nid, u64 start, u64 size) return __add_pages(nid, zone, start_pfn, nr_pages); } + +#ifdef CONFIG_MEMORY_HOTREMOVE +int arch_remove_memory(unsigned long start, unsigned long size) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + + return __remove_pages(start_pfn, nr_pages); +} +#endif #endif /* diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 2b6b4a3..f1554a9 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -675,6 +675,166 @@ int arch_add_memory(int nid, u64 start, u64 size) } EXPORT_SYMBOL_GPL(arch_add_memory); +static void __meminit +phys_pte_remove(pte_t *pte_page, unsigned long addr, unsigned long end) +{ + unsigned pages = 0; + int i = pte_index(addr); + + pte_t *pte = pte_page + pte_index(addr); + + for (; i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) { + + if (addr >= end) + break; + + if (!pte_present(*pte)) + continue; + + pages++; + set_pte(pte, __pte(0)); + } + + update_page_count(PG_LEVEL_4K, -pages); +} + +static void __meminit +phys_pmd_remove(pmd_t *pmd_page, unsigned long addr, unsigned long end) +{ + unsigned long pages = 0, next; + int i = pmd_index(addr); + + for (; i < PTRS_PER_PMD; i++, addr = next) { + unsigned long pte_phys; + pmd_t *pmd = pmd_page + pmd_index(addr); + pte_t *pte; + + if (addr >= end) + break; + + next = (addr & PMD_MASK) + PMD_SIZE; + + if (!pmd_present(*pmd)) + continue; + + if (pmd_large(*pmd)) { + if ((addr & ~PMD_MASK) == 0 && next <= end) { + set_pmd(pmd, __pmd(0)); + pages++; + continue; + } + + /* + * We use 2M page, but we need to remove part of them, + * so split 2M page to 4K page. + */ + pte = alloc_low_page(&pte_phys); + __split_large_page((pte_t *)pmd, addr, pte); + + spin_lock(&init_mm.page_table_lock); + pmd_populate_kernel(&init_mm, pmd, __va(pte_phys)); + spin_unlock(&init_mm.page_table_lock); + } + + spin_lock(&init_mm.page_table_lock); + pte = map_low_page((pte_t *)pmd_page_vaddr(*pmd)); + phys_pte_remove(pte, addr, end); + unmap_low_page(pte); + spin_unlock(&init_mm.page_table_lock); + } + update_page_count(PG_LEVEL_2M, -pages); +} + +static void __meminit +phys_pud_remove(pud_t *pud_page, unsigned long addr, unsigned long end) +{ + unsigned long pages = 0, next; + int i = pud_index(addr); + + for (; i < PTRS_PER_PUD; i++, addr = next) { + unsigned long pmd_phys; + pud_t *pud = pud_page + pud_index(addr); + pmd_t *pmd; + + if (addr >= end) + break; + + next = (addr & PUD_MASK) + PUD_SIZE; + + if (!pud_present(*pud)) + continue; + + if (pud_large(*pud)) { + if ((addr & ~PUD_MASK) == 0 && next <= end) { + set_pud(pud, __pud(0)); + pages++; + continue; + } + + /* + * We use 1G page, but we need to remove part of them, + * so split 1G page to 2M page. + */ + pmd = alloc_low_page(&pmd_phys); + __split_large_page((pte_t *)pud, addr, (pte_t *)pmd); + + spin_lock(&init_mm.page_table_lock); + pud_populate(&init_mm, pud, __va(pmd_phys)); + spin_unlock(&init_mm.page_table_lock); + } + + pmd = map_low_page(pmd_offset(pud, 0)); + phys_pmd_remove(pmd, addr, end); + unmap_low_page(pmd); + __flush_tlb_all(); + } + __flush_tlb_all(); + + update_page_count(PG_LEVEL_1G, -pages); +} + +void __meminit +kernel_physical_mapping_remove(unsigned long start, unsigned long end) +{ + unsigned long next; + + start = (unsigned long)__va(start); + end = (unsigned long)__va(end); + + for (; start < end; start = next) { + pgd_t *pgd = pgd_offset_k(start); + pud_t *pud; + + next = (start + PGDIR_SIZE) & PGDIR_MASK; + if (next > end) + next = end; + + if (!pgd_present(*pgd)) + continue; + + pud = map_low_page((pud_t *)pgd_page_vaddr(*pgd)); + phys_pud_remove(pud, __pa(start), __pa(end)); + unmap_low_page(pud); + } + + __flush_tlb_all(); +} + +#ifdef CONFIG_MEMORY_HOTREMOVE +int __ref arch_remove_memory(unsigned long start, unsigned long size) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + int ret; + + ret = __remove_pages(start_pfn, nr_pages); + WARN_ON_ONCE(ret); + + kernel_physical_mapping_remove(start, start + size); + + return ret; +} +#endif #endif /* CONFIG_MEMORY_HOTPLUG */ static struct kcore_list kcore_vsyscall; diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 931930a..c22963d 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -501,21 +501,13 @@ out_unlock: return do_split; } -static int split_large_page(pte_t *kpte, unsigned long address) +int __split_large_page(pte_t *kpte, unsigned long address, pte_t *pbase) { unsigned long pfn, pfninc = 1; unsigned int i, level; - pte_t *pbase, *tmp; + pte_t *tmp; pgprot_t ref_prot; - struct page *base; - - if (!debug_pagealloc) - spin_unlock(&cpa_lock); - base = alloc_pages(GFP_KERNEL | __GFP_NOTRACK, 0); - if (!debug_pagealloc) - spin_lock(&cpa_lock); - if (!base) - return -ENOMEM; + struct page *base = virt_to_page(pbase); spin_lock(&pgd_lock); /* @@ -523,10 +515,11 @@ static int split_large_page(pte_t *kpte, unsigned long address) * up for us already: */ tmp = lookup_address(address, &level); - if (tmp != kpte) - goto out_unlock; + if (tmp != kpte) { + spin_unlock(&pgd_lock); + return 1; + } - pbase = (pte_t *)page_address(base); paravirt_alloc_pte(&init_mm, page_to_pfn(base)); ref_prot = pte_pgprot(pte_clrhuge(*kpte)); /* @@ -579,17 +572,27 @@ static int split_large_page(pte_t *kpte, unsigned long address) * going on. */ __flush_tlb_all(); + spin_unlock(&pgd_lock); - base = NULL; + return 0; +} -out_unlock: - /* - * If we dropped out via the lookup_address check under - * pgd_lock then stick the page back into the pool: - */ - if (base) +static int split_large_page(pte_t *kpte, unsigned long address) +{ + pte_t *pbase; + struct page *base; + + if (!debug_pagealloc) + spin_unlock(&cpa_lock); + base = alloc_pages(GFP_KERNEL | __GFP_NOTRACK, 0); + if (!debug_pagealloc) + spin_lock(&cpa_lock); + if (!base) + return -ENOMEM; + + pbase = (pte_t *)page_address(base); + if (__split_large_page(kpte, address, pbase)) __free_page(base); - spin_unlock(&pgd_lock); return 0; } diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index 8bf820d..0d500be 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -85,6 +85,7 @@ extern void __online_page_free(struct page *page); #ifdef CONFIG_MEMORY_HOTREMOVE extern bool is_pageblock_removable_nolock(struct page *page); +extern int arch_remove_memory(unsigned long start, unsigned long size); #endif /* CONFIG_MEMORY_HOTREMOVE */ /* reasonably generic interface to expand the physical pages in a zone */ diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index a9e1579..0c932e1 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1071,6 +1071,7 @@ int __ref remove_memory(int nid, u64 start, u64 size) /* remove memmap entry */ firmware_map_remove(start, start + size, "System RAM"); + arch_remove_memory(start, size); out: unlock_memory_hotplug(); return ret;
We don't call __add_pages() directly in the function add_memory() because some other architecture related things need to be done before or after calling __add_pages(). So we should introduce a new function arch_remove_memory() to revert the things done in arch_add_memory(). Note: the function for s390 is not implemented(I don't know how to implement it for s390). CC: David Rientjes <rientjes@google.com> CC: Jiang Liu <liuj97@gmail.com> CC: Len Brown <len.brown@intel.com> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org> CC: Paul Mackerras <paulus@samba.org> CC: Christoph Lameter <cl@linux.com> Cc: Minchan Kim <minchan.kim@gmail.com> CC: Andrew Morton <akpm@linux-foundation.org> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> CC: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> --- arch/ia64/mm/init.c | 16 ++++ arch/powerpc/mm/mem.c | 14 +++ arch/s390/mm/init.c | 8 ++ arch/sh/mm/init.c | 15 +++ arch/tile/mm/init.c | 8 ++ arch/x86/include/asm/pgtable_types.h | 1 + arch/x86/mm/init_32.c | 10 ++ arch/x86/mm/init_64.c | 160 ++++++++++++++++++++++++++++++++++ arch/x86/mm/pageattr.c | 47 +++++----- include/linux/memory_hotplug.h | 1 + mm/memory_hotplug.c | 1 + 11 files changed, 259 insertions(+), 22 deletions(-)