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WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.7.1 MIME-Version: 1.0 In-Reply-To: <20230326232508.GB19631@lst.de> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.179.24] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpemm100009.china.huawei.com (7.185.36.113) X-CFilter-Loop: Reflected X-Rspamd-Queue-Id: DAF7980002 X-Rspamd-Server: rspam09 X-Rspam-User: X-Stat-Signature: ye5s1x4uja8axqizmox1taixqsm39kws X-HE-Tag: 1679880161-886049 X-HE-Meta: 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 43ogDegq AmpQ0cPLWkPznuviUE9i8GeP905P42AmYHenADLZ9MtjmxgAK21D5fpCRkohpalemQ0H9G5qov3QLmjeoJZOU+aonN4PMSAlTCINe2+Ir095INofftK2vueWcgbrRHDEPGlP8AOHPj/PvMvoQZ6Nvp15SWw== 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: On 2023/3/27 7:25, Christoph Hellwig wrote: > On Sun, Mar 26, 2023 at 01:53:27PM +0900, Sergey Senozhatsky wrote: >>>> + if (kstrtobool(val, &res)) >>>> + return -EINVAL; >>>> + >>>> + /* no change required */ >>>> + if (res == *(bool *)kp->arg) >>>> + return 0; >>> Bool kernel param can be any of these letters 'YyTt1NnFf0'. Doing things >>> to kp->arg outside of kernel/params.c is not going to be easy, let's not >>> even try. >> Please disregard my previous email. kp->arg is always true or false >> at this point. I'd still prefer to not do kp->arg in zswap. > The whole parameter handling in zswap is a mess and I don't really > have a good idea how to solve it all. > > But for this "paramter not changed" case I think we can helper a lot > by adding a core moduleparam.h helper to encapsule it. I.e.: > > static inline bool param_bool_unchanged(bool val, > const struct kernel_param *kp) > > return val == *(bool *)kp->arg); > } > > and at least keep it out of zswap. Thanks for your advice. I will try this way. > > . >