+ mm-z3fold-remove-magic-number-in-z3fold_create_pool.patch added to -mm tree

+ mm-z3fold-remove-magic-number-in-z3fold_create_pool.patch added to -mm tree

[akpm]

The patch titled
     Subject: mm/z3fold: remove magic number in z3fold_create_pool()
has been added to the -mm tree.  Its filename is
     mm-z3fold-remove-magic-number-in-z3fold_create_pool.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-z3fold-remove-magic-number-in-z3fold_create_pool.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-z3fold-remove-magic-number-in-z3fold_create_pool.patch

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------------------------------------------------------
From: Miaohe Lin <linmiaohe@huawei.com>
Subject: mm/z3fold: remove magic number in z3fold_create_pool()

It's meaningless to pass a magic number 2 to __alloc_percpu() as there is
a minimum alignment size of PCPU_MIN_ALLOC_SIZE (> 2) in it.  Also there
is no special alignment requirement for unbuddied.  So we could replace
this magic number with nature alignment, i.e.  __alignof__(struct
list_head), to improve readability.

Link: https://lkml.kernel.org/r/20210619093151.1492174-4-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Vitaly Wool <vitaly.wool@konsulko.com>
Cc: Hillf Danton <hdanton@sina.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/z3fold.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/mm/z3fold.c~mm-z3fold-remove-magic-number-in-z3fold_create_pool
+++ a/mm/z3fold.c
@@ -998,7 +998,8 @@ static struct z3fold_pool *z3fold_create
 		goto out_c;
 	spin_lock_init(&pool->lock);
 	spin_lock_init(&pool->stale_lock);
-	pool->unbuddied = __alloc_percpu(sizeof(struct list_head)*NCHUNKS, 2);
+	pool->unbuddied = __alloc_percpu(sizeof(struct list_head) * NCHUNKS,
+					 __alignof__(struct list_head));
 	if (!pool->unbuddied)
 		goto out_pool;
 	for_each_possible_cpu(cpu) {
_

Patches currently in -mm which might be from linmiaohe@huawei.com are

mm-swapfile-use-percpu_ref-to-serialize-against-concurrent-swapoff.patch
swap-fix-do_swap_page-race-with-swapoff.patch
mm-swap-remove-confusing-checking-for-non_swap_entry-in-swap_ra_info.patch
mm-shmem-fix-shmem_swapin-race-with-swapoff.patch
mm-swapfile-move-get_swap_page_of_type-under-config_hibernation.patch
mm-swapfile-move-get_swap_page_of_type-under-config_hibernation-fix.patch
mm-swapfile-move-get_swap_page_of_type-under-config_hibernation-fix-2.patch
mm-swap-remove-unused-local-variable-nr_shadows.patch
mm-swap_slotsc-delete-meaningless-forward-declarations.patch
mm-huge_memoryc-remove-dedicated-macro-hpage_cache_index_mask.patch
mm-huge_memoryc-use-page-deferred_list.patch
mm-huge_memoryc-add-missing-read-only-thp-checking-in-transparent_hugepage_enabled.patch
mm-huge_memoryc-add-missing-read-only-thp-checking-in-transparent_hugepage_enabled-v4.patch
mm-huge_memoryc-remove-unnecessary-tlb_remove_page_size-for-huge-zero-pmd.patch
mm-huge_memoryc-dont-discard-hugepage-if-other-processes-are-mapping-it.patch
mm-z3fold-define-macro-nchunks-as-total_chunks-zhdr_chunks.patch
mm-z3fold-avoid-possible-underflow-in-z3fold_alloc.patch
mm-z3fold-remove-magic-number-in-z3fold_create_pool.patch
mm-z3fold-remove-unused-function-handle_to_z3fold_header.patch
mm-z3fold-fix-potential-memory-leak-in-z3fold_destroy_pool.patch
mm-z3fold-use-release_z3fold_page_locked-to-release-locked-z3fold-page.patch
mm-zbud-reuse-unbuddied-as-buddied-in-zbud_pool.patch
mm-zbud-dont-export-any-zbud-api.patch
mm-zswapc-remove-unused-function-zswap_debugfs_exit.patch
mm-zswapc-avoid-unnecessary-copy-in-at-map-time.patch
mm-zswapc-fix-two-bugs-in-zswap_writeback_entry.patch