Naoya Horiguchi wrote: > Thp related code also uses per process mm->page_table_lock now. > So making it fine-grained can provide better performance. > > This patch makes thp support split page table lock by using page->ptl > of the pages storing "pmd_trans_huge" pmds. > > Some functions like pmd_trans_huge_lock() and page_check_address_pmd() > are expected by their caller to pass back the pointer of ptl, so this > patch adds to those functions new arguments for that. Rather than that, > this patch gives only straightforward replacement. > > ChangeLog v3: > - fixed argument of huge_pmd_lockptr() in copy_huge_pmd() > - added missing declaration of ptl in do_huge_pmd_anonymous_page() > > Signed-off-by: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> Generally, looks good. Few notes: I believe you need to convert __pte_alloc() to new locking. Not sure about __pte_alloc_kernel(). Have you check all rest mm->page_table_lock, that they shouldn't be converted to new locking? You use uninitialized_var() a lot. It's ugly. I've check few places (task_mmu.c, copy_huge_pmd) and have found a reason why we need it there. Why? You often do + ptl = huge_pmd_lockptr(mm, pmd); + spin_lock(ptl); Should we have a helper to combine them? huge_pmd_lock()? -- Kirill A. Shutemov -- 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>