Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932079Ab2K1TDw (ORCPT ); Wed, 28 Nov 2012 14:03:52 -0500 Received: from userp1040.oracle.com ([156.151.31.81]:30010 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755040Ab2K1TDv (ORCPT ); Wed, 28 Nov 2012 14:03:51 -0500 Date: Wed, 28 Nov 2012 14:02:49 -0500 From: Konrad Rzeszutek Wilk To: Yinghai Lu Cc: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Jacob Shin , Andrew Morton , Stefano Stabellini , linux-kernel@vger.kernel.org Subject: Re: [PATCH v8 29/46] x86, mm: only call early_ioremap_page_table_range_init() once Message-ID: <20121128190249.GR21266@phenom.dumpdata.com> References: <1353123563-3103-1-git-send-email-yinghai@kernel.org> <1353123563-3103-30-git-send-email-yinghai@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1353123563-3103-30-git-send-email-yinghai@kernel.org> User-Agent: Mutt/1.5.21 (2010-09-15) X-Source-IP: ucsinet22.oracle.com [156.151.31.94] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5079 Lines: 152 On Fri, Nov 16, 2012 at 07:39:06PM -0800, Yinghai Lu wrote: > On 32bit, before patcheset that only set page table for ram, we only > call that one time. Um.. Which patchset? x86, mm: Only direct map addresses that are marked as E820_RAM? > > Now, we are calling that during every init_memory_mapping if we have holes > under max_low_pfn. > > We should only call it one time after all ranges under max_low_page get > mapped just like we did before. > > Also that could avoid the risk to run out of pgt_buf in BRK. ^^- 'of running out of pgt_buf in BRK.' > > Need to update page_table_range_init() to count the pages for kmap page table > at first, and use new added alloc_low_pages() to get pages in sequence. > That will conform to the requirement that pages need to be in low to high order. > > Signed-off-by: Yinghai Lu > --- > arch/x86/mm/init.c | 13 +++++-------- > arch/x86/mm/init_32.c | 47 +++++++++++++++++++++++++++++++++++++++++------ > 2 files changed, 46 insertions(+), 14 deletions(-) > > diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c > index cb4f8ba..bed4888 100644 > --- a/arch/x86/mm/init.c > +++ b/arch/x86/mm/init.c > @@ -343,14 +343,6 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, > ret = kernel_physical_mapping_init(mr[i].start, mr[i].end, > mr[i].page_size_mask); > > -#ifdef CONFIG_X86_32 > - early_ioremap_page_table_range_init(); > - > - load_cr3(swapper_pg_dir); > -#endif > - > - __flush_tlb_all(); > - > add_pfn_range_mapped(start >> PAGE_SHIFT, ret >> PAGE_SHIFT); > > return ret >> PAGE_SHIFT; > @@ -447,7 +439,12 @@ void __init init_mem_mapping(void) > /* can we preseve max_low_pfn ?*/ > max_low_pfn = max_pfn; > } > +#else > + early_ioremap_page_table_range_init(); > + load_cr3(swapper_pg_dir); > + __flush_tlb_all(); > #endif > + > early_memtest(0, max_pfn_mapped << PAGE_SHIFT); > } > > diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c > index a7f2df1..0ae1ba8 100644 > --- a/arch/x86/mm/init_32.c > +++ b/arch/x86/mm/init_32.c > @@ -135,8 +135,39 @@ pte_t * __init populate_extra_pte(unsigned long vaddr) > return one_page_table_init(pmd) + pte_idx; > } > > +static unsigned long __init > +page_table_range_init_count(unsigned long start, unsigned long end) > +{ > + unsigned long count = 0; > +#ifdef CONFIG_HIGHMEM > + int pmd_idx_kmap_begin = fix_to_virt(FIX_KMAP_END) >> PMD_SHIFT; > + int pmd_idx_kmap_end = fix_to_virt(FIX_KMAP_BEGIN) >> PMD_SHIFT; > + int pgd_idx, pmd_idx; > + unsigned long vaddr; > + > + if (pmd_idx_kmap_begin == pmd_idx_kmap_end) > + return 0; > + > + vaddr = start; > + pgd_idx = pgd_index(vaddr); > + > + for ( ; (pgd_idx < PTRS_PER_PGD) && (vaddr != end); pgd_idx++) { > + for (; (pmd_idx < PTRS_PER_PMD) && (vaddr != end); > + pmd_idx++) { > + if ((vaddr >> PMD_SHIFT) >= pmd_idx_kmap_begin && > + (vaddr >> PMD_SHIFT) <= pmd_idx_kmap_end) > + count++; > + vaddr += PMD_SIZE; > + } > + pmd_idx = 0; > + } > +#endif > + return count; > +} > + > static pte_t *__init page_table_kmap_check(pte_t *pte, pmd_t *pmd, > - unsigned long vaddr, pte_t *lastpte) > + unsigned long vaddr, pte_t *lastpte, > + void **adr) > { > #ifdef CONFIG_HIGHMEM > /* > @@ -150,16 +181,15 @@ static pte_t *__init page_table_kmap_check(pte_t *pte, pmd_t *pmd, > > if (pmd_idx_kmap_begin != pmd_idx_kmap_end > && (vaddr >> PMD_SHIFT) >= pmd_idx_kmap_begin > - && (vaddr >> PMD_SHIFT) <= pmd_idx_kmap_end > - && ((__pa(pte) >> PAGE_SHIFT) < pgt_buf_start > - || (__pa(pte) >> PAGE_SHIFT) >= pgt_buf_end)) { > + && (vaddr >> PMD_SHIFT) <= pmd_idx_kmap_end) { > pte_t *newpte; > int i; > > BUG_ON(after_bootmem); > - newpte = alloc_low_page(); > + newpte = *adr; > for (i = 0; i < PTRS_PER_PTE; i++) > set_pte(newpte + i, pte[i]); > + *adr = (void *)(((unsigned long)(*adr)) + PAGE_SIZE); > > paravirt_alloc_pte(&init_mm, __pa(newpte) >> PAGE_SHIFT); > set_pmd(pmd, __pmd(__pa(newpte)|_PAGE_TABLE)); > @@ -193,6 +223,11 @@ page_table_range_init(unsigned long start, unsigned long end, pgd_t *pgd_base) > pgd_t *pgd; > pmd_t *pmd; > pte_t *pte = NULL; > + unsigned long count = page_table_range_init_count(start, end); > + void *adr = NULL; > + > + if (count) > + adr = alloc_low_pages(count); > > vaddr = start; > pgd_idx = pgd_index(vaddr); > @@ -205,7 +240,7 @@ page_table_range_init(unsigned long start, unsigned long end, pgd_t *pgd_base) > for (; (pmd_idx < PTRS_PER_PMD) && (vaddr != end); > pmd++, pmd_idx++) { > pte = page_table_kmap_check(one_page_table_init(pmd), > - pmd, vaddr, pte); > + pmd, vaddr, pte, &adr); > > vaddr += PMD_SIZE; > } > -- > 1.7.7 -- 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/