From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4A18AC02198 for ; Wed, 12 Feb 2025 05:13:09 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C05916B0082; Wed, 12 Feb 2025 00:13:08 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id B8F1C6B0083; Wed, 12 Feb 2025 00:13:08 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A30426B0085; Wed, 12 Feb 2025 00:13:08 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 85A736B0082 for ; Wed, 12 Feb 2025 00:13:08 -0500 (EST) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 241A680A2D for ; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 70D5520006 X-Stat-Signature: ezgrjobnjnr4318hhgixj3hyecf3f5rw X-Rspam-User: X-HE-Tag: 1739337186-421023 X-HE-Meta: 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 WJMTFKty mvNiqMjvEE2gjdSy6FPUI6Qz59JNQEqUQGPGn6BtlMIg0wifFh4XAPN8rOBi5+bJM97mUwQ4Zh0RguA2B1wTVRo6YSlzYmLcnaaFyBo10mhjLj9ntXuNxbfJgQLyBtnKQbQEjbiuuROx4XkfZHgTLLQR5NtrBL/du0wddHotyUDR/2MLEnNxpVOdplVFPTcp7xJYy X-Bogosity: Ham, tests=bogofilter, spamicity=0.000108, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 12/02/25 8:28 am, Liu Ye wrote: > There are multiple locations in mm.h where (folio->_flags_1 & 0xff) is > used. Write it as a macro definition to improve the readability and > maintainability of the code. > > Signed-off-by: Liu Ye > --- > include/linux/mm.h | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > diff --git a/include/linux/mm.h b/include/linux/mm.h > index 7b1068ddcbb7..750e75f45557 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -1098,6 +1098,8 @@ int vma_is_stack_for_current(struct vm_area_struct *vma); > struct mmu_gather; > struct inode; > > +#define FOLIO_ORDER(folio) ((folio)->_flags_1 & 0xff) > + > /* > * compound_order() can be called without holding a reference, which means > * that niceties like page_folio() don't work. These callers should be > @@ -1111,7 +1113,7 @@ static inline unsigned int compound_order(struct page *page) > > if (!test_bit(PG_head, &folio->flags)) > return 0; > - return folio->_flags_1 & 0xff; > + return FOLIO_ORDER(folio); > } > > /** > @@ -1127,7 +1129,7 @@ static inline unsigned int folio_order(const struct folio *folio) > { > if (!folio_test_large(folio)) > return 0; > - return folio->_flags_1 & 0xff; > + return FOLIO_ORDER(folio); > } > > #include > @@ -2061,7 +2063,7 @@ static inline long folio_nr_pages(const struct folio *folio) > #ifdef CONFIG_64BIT > return folio->_folio_nr_pages; > #else > - return 1L << (folio->_flags_1 & 0xff); > + return 1L << FOLIO_ORDER(folio); > #endif > } > > @@ -2086,7 +2088,7 @@ static inline unsigned long compound_nr(struct page *page) > #ifdef CONFIG_64BIT > return folio->_folio_nr_pages; > #else > - return 1L << (folio->_flags_1 & 0xff); > + return 1L << FOLIO_ORDER(folio); > #endif > } > Personally I do not think this is improving readability. You are introducing one more macro for people to decipher instead of directly seeing folio->_flags_1 & 0xff. This is similar to whether to write if (x) => do_stuff(), or if (x != 0) => do_stuff(). The former is more "readable" by convention but the latter makes it easier and obvious to understand.