The current code that checks if migrating misplaced transhuge page is needed is pretty hard to follow. Rework it and add a comment to make its logic more clear and improve readability.
Signed-off-by: Miaohe Lin <[email protected]> --- mm/huge_memory.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 01b96c638e73..23964adf5db2 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1462,12 +1462,6 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t pmd) */ page_locked = trylock_page(page); target_nid = mpol_misplaced(page, vma, haddr); - if (target_nid == NUMA_NO_NODE) { - /* If the page was locked, there are no parallel migrations */ - if (page_locked) - goto clear_pmdnuma; - } - /* Migration could have started since the pmd_trans_migrating check */ if (!page_locked) { page_nid = NUMA_NO_NODE; @@ -1476,6 +1470,11 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t pmd) spin_unlock(vmf->ptl); put_and_wait_on_page_locked(page, TASK_UNINTERRUPTIBLE); goto out; + } else if (target_nid == NUMA_NO_NODE) { + /* There are no parallel migrations and page is in the right + * node. Clear the numa hinting info in this pmd. + */ + goto clear_pmdnuma; } /* -- 2.19.1
