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charset=us-ascii Content-Disposition: inline In-Reply-To: <20260128-swap-table-p3-v2-6-fe0b67ef0215@tencent.com> X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 1422518000D X-Stat-Signature: 8i5aernjdyxco7y9ypd67z5uhwm9zxc4 X-Rspam-User: X-HE-Tag: 1769671713-207802 X-HE-Meta: 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 3Z1/G4Kw Z6w9f/PHpJ4ku/ZxXWWlcaeI7P45oL+opYB1LKbi2IGONLRHvFRP7ume24FOiv5DyPB/UdmT4Tw0EDBGn6DJm13I/wclCZUhCeAJai41QyTkgYj3adWWVibD9ZIoCylRmLUDu9HxTIoew+BYInmbT28lxRzDHAVrqqNk1fe/fUClCOKLFU3CLd/9y3Tk5bTO/z+K0XDjtQu+zvtDRSfetiINS0VKR8bIdP6bf/PlFj1hEZI1YqBramdLXCZ3WR75kh4gk/caT+6CHMHQ= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, 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 Wed, Jan 28, 2026 at 05:28:30PM +0800, Kairui Song wrote: > From: Kairui Song > +static inline bool swp_tb_is_countable(unsigned long swp_tb) > +{ > + return (swp_tb_is_shadow(swp_tb) || swp_tb_is_folio(swp_tb) || > + swp_tb_is_null(swp_tb)); > +} What do you think about simplifying swp_tb_is_countable by just checking !swp_tb_is_bad(swp_tb)? Since this function appears to be called frequently, reducing the number of comparisons would be beneficial for performance. If validation is necessary for debugging perhaps we could introduce a separate version for debugging purposes. > +static inline int swp_tb_get_count(unsigned long swp_tb) > +{ > + if (swp_tb_is_countable(swp_tb)) > + return __swp_tb_get_count(swp_tb); > + return -EINVAL; > } Or, could we simply drop the check in swp_tb_get_count and call __swp_tb_get_count directly? If we define SWP_TB_BAD to have 0 in the count bits (MSB), it will naturally yield a count of 0. Thanks! Youngjun Park