The patch titled Subject: mm/hugetlb: use list_splice to merge two list at once has been added to the -mm tree. Its filename is mm-hugetlb-use-list_splice-to-merge-two-list-at-once.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/mm-hugetlb-use-list_splice-to-merge-two-list-at-once.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/mm-hugetlb-use-list_splice-to-merge-two-list-at-once.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/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Wei Yang <richard.weiyang@xxxxxxxxxxxxxxxxx> Subject: mm/hugetlb: use list_splice to merge two list at once Instead of add allocated file_region one by one to region_cache, we could use list_splice to merge two list at once. Also we know the number of entries in the list, increase the number directly. Link: https://lkml.kernel.org/r/20200831022351.20916-4-richard.weiyang@xxxxxxxxxxxxxxxxx Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxxxxxxxxxx> Reviewed-by: Baoquan He <bhe@xxxxxxxxxx> Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/hugetlb.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) --- a/mm/hugetlb.c~mm-hugetlb-use-list_splice-to-merge-two-list-at-once +++ a/mm/hugetlb.c @@ -443,11 +443,8 @@ static int allocate_file_region_entries( spin_lock(&resv->lock); - list_for_each_entry_safe(rg, trg, &allocated_regions, link) { - list_del(&rg->link); - list_add(&rg->link, &resv->region_cache); - resv->region_cache_count++; - } + list_splice(&allocated_regions, &resv->region_cache); + resv->region_cache_count += to_allocate; } return 0; _ Patches currently in -mm which might be from richard.weiyang@xxxxxxxxxxxxxxxxx are mm-mmap-rename-__vma_unlink_common-to-__vma_unlink.patch mm-mmap-leverage-vma_rb_erase_ignore-to-implement-vma_rb_erase.patch mm-mmap-leave-adjust_next-as-virtual-address-instead-of-page-frame-number.patch mm-hugetlb-not-necessary-to-coalesce-regions-recursively.patch mm-hugetlb-remove-vm_bug_onnrg-in-get_file_region_entry_from_cache.patch mm-hugetlb-use-list_splice-to-merge-two-list-at-once.patch mm-hugetlb-count-file_region-to-be-added-when-regions_needed-=-null.patch mm-hugetlb-a-page-from-buddy-is-not-on-any-list.patch mm-hugetlb-narrow-the-hugetlb_lock-protection-area-during-preparing-huge-page.patch mm-hugetlb-take-the-free-hpage-during-the-iteration-directly.patch mm-page_reporting-drop-stale-list-head-check-in-page_reporting_cycle.patch bitops-simplify-get_count_order_long.patch bitops-use-the-same-mechanism-for-get_count_order.patch