Subject: + mm-vmalloc-interchage-the-implementation-of-vmalloc_to_pfnpage.patch added to -mm tree To: nasa4836@xxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Mon, 02 Dec 2013 15:59:42 -0800 The patch titled Subject: mm/vmalloc: interchage the implementation of vmalloc_to_{pfn,page} has been added to the -mm tree. Its filename is mm-vmalloc-interchage-the-implementation-of-vmalloc_to_pfnpage.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-vmalloc-interchage-the-implementation-of-vmalloc_to_pfnpage.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-vmalloc-interchage-the-implementation-of-vmalloc_to_pfnpage.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Jianyu Zhan <nasa4836@xxxxxxxxx> Subject: mm/vmalloc: interchage the implementation of vmalloc_to_{pfn,page} Currently we are implementing vmalloc_to_pfn() as a wrapper around vmalloc_to_page(), which is implemented as follow: 1. walks the page talbes to generates the corresponding pfn, 2. then converts the pfn to struct page, 3. returns it. And vmalloc_to_pfn() re-wraps vmalloc_to_page() to get the pfn. This seems too circuitous, so this patch reverses the way: implement vmalloc_to_page() as a wrapper around vmalloc_to_pfn(). This makes vmalloc_to_pfn() and vmalloc_to_page() slightly more efficient. No functional change. Signed-off-by: Jianyu Zhan <nasa4836@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/vmalloc.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff -puN mm/vmalloc.c~mm-vmalloc-interchage-the-implementation-of-vmalloc_to_pfnpage mm/vmalloc.c --- a/mm/vmalloc.c~mm-vmalloc-interchage-the-implementation-of-vmalloc_to_pfnpage +++ a/mm/vmalloc.c @@ -220,12 +220,12 @@ int is_vmalloc_or_module_addr(const void } /* - * Walk a vmap address to the struct page it maps. + * Walk a vmap address to the physical pfn it maps to. */ -struct page *vmalloc_to_page(const void *vmalloc_addr) +unsigned long vmalloc_to_pfn(const void *vmalloc_addr) { unsigned long addr = (unsigned long) vmalloc_addr; - struct page *page = NULL; + unsigned long pfn; pgd_t *pgd = pgd_offset_k(addr); /* @@ -244,23 +244,23 @@ struct page *vmalloc_to_page(const void ptep = pte_offset_map(pmd, addr); pte = *ptep; if (pte_present(pte)) - page = pte_page(pte); + pfn = pte_page(pte); pte_unmap(ptep); } } } - return page; + return pfn; } -EXPORT_SYMBOL(vmalloc_to_page); +EXPORT_SYMBOL(vmalloc_to_pfn); /* - * Map a vmalloc()-space virtual address to the physical page frame number. + * Map a vmalloc()-space virtual address to the struct page. */ -unsigned long vmalloc_to_pfn(const void *vmalloc_addr) +struct page *vmalloc_to_page(const void *vmalloc_addr) { - return page_to_pfn(vmalloc_to_page(vmalloc_addr)); + return pfn_to_page(vmalloc_to_pfn(vmalloc_addr)); } -EXPORT_SYMBOL(vmalloc_to_pfn); +EXPORT_SYMBOL(vmalloc_to_page); /*** Global kva allocator ***/ _ Patches currently in -mm which might be from nasa4836@xxxxxxxxx are mm-vmalloc-interchage-the-implementation-of-vmalloc_to_pfnpage.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html