On 08/20/2013 12:47 AM, Andrew Morton wrote: > On Mon, 19 Aug 2013 14:23:42 +0200 Vlastimil Babka <vbabka@xxxxxxx> wrote: > >> Currently munlock_vma_pages_range() calls follow_page_mask() to obtain each >> struct page. This entails repeated full page table translations and page table >> lock taken for each page separately. >> >> This patch attempts to avoid the costly follow_page_mask() where possible, by >> iterating over ptes within single pmd under single page table lock. The first >> pte is obtained by get_locked_pte() for non-THP page acquired by the initial >> follow_page_mask(). The latter function is also used as a fallback in case >> simple pte_present() and vm_normal_page() are not sufficient to obtain the >> struct page. > > Patch #7 appears to provide significant performance gains, but the > improvement wasn't individually described here, unlike the other > patches. Oops I forgot to mention this here. Can you please add the following to the comment then? Thanks. After this patch, a 13% speedup was measured for munlocking a 56GB large memory area with THP disabled. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>