From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-130.freemail.mail.aliyun.com (out30-130.freemail.mail.aliyun.com [115.124.30.130]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7663A1A9FA4 for ; Tue, 19 May 2026 02:22:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.130 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779157380; cv=none; b=o5nTvENxPlB4RtDBcoH4l54zX6mU4Ms2NkkGHmGzDVCyyvlVRcmZFnDg1SDm66nPDt6t/kxcR874V6jE917UIVDwlPUmWZIhTXv3RRhvj0SgocZPvxm59gAQ9FXwBAy/A0fYHELG0syi4194t1If3sjwdsU4IjJaWRMe4c0GyHY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779157380; c=relaxed/simple; bh=W8Mi+taakRYZvhvYZ3A9y26C8qUJWQLIxKL/AaV/lfk=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=fyGlW/HzSF1gnHCTAAvrVpZRTb/szcgdDFWRDlMYuZ4LtWOUerCJPZS0489MIJ/5JCpWyG4v0glTl1TKEtk/7cj9bHWOac6j3iIBVEdkp7qbvEAYRD/ciyp1/CNwD7M77dWHi1Iv0CHuBQ08A39MXfo/Elw0ec3feSEnzjFaV5o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=dGSDxXUq; arc=none smtp.client-ip=115.124.30.130 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="dGSDxXUq" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1779157375; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=LIk/NWSgUYZOSk5yFuK7TNfkGqGRO+5XC4I2PR2ONr8=; b=dGSDxXUqnWyOPGgZW+lBMdRVnf70XVbx+JTHL68FiLlKUKHyXGd51brUzuIKqRjLyLRbdQe4W4S+4U4JyX0k4akjslO1P/g8NeaMYF7IPr0UJibZR0FQoYWkoE9rUFZM6lF2sR0T9YRwt9PQbTtsmLteM0CJUcuogj37uCtPdDA= X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R861e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033032089153;MF=baolin.wang@linux.alibaba.com;NM=1;PH=DS;RN=16;SR=0;TI=SMTPD_---0X3Dv23q_1779157372; Received: from 30.74.112.128(mailfrom:baolin.wang@linux.alibaba.com fp:SMTPD_---0X3Dv23q_1779157372 cluster:ay36) by smtp.aliyun-inc.com; Tue, 19 May 2026 10:22:53 +0800 Message-ID: <72d2721a-f52c-4330-bdb0-4f0615512956@linux.alibaba.com> Date: Tue, 19 May 2026 10:22:51 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 1/2] mm: shmem: refactor thpsize_shmem_enabled_store() with sysfs_match_string() To: ranxiaokai627@163.com, hughd@google.com, akpm@linux-foundation.org Cc: leitao@debian.org, ljs@kernel.org, ziy@nvidia.com, liam@infradead.org, npache@redhat.com, ryan.roberts@arm.com, dev.jain@arm.com, baohua@kernel.org, lance.yang@linux.dev, david@kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, ran.xiaokai@zte.com.cn References: <20260518123238.56344-1-ranxiaokai627@163.com> <20260518123238.56344-2-ranxiaokai627@163.com> From: Baolin Wang In-Reply-To: <20260518123238.56344-2-ranxiaokai627@163.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 5/18/26 8:32 PM, ranxiaokai627@163.com wrote: > From: Ran Xiaokai > > Inspired by commit 82d9ff648c6c ("mm: huge_memory: refactor > anon_enabled_store() with set_anon_enabled_mode()"), refactor > thpsize_shmem_enabled_store() using sysfs_match_string(). > This eliminates the duplicated spin_lock/unlock(), set/clear_bit(), > calls across all branches, reducing code duplication. > > Behavioral change: > Call start_stop_khugepaged() only when the mode actually changes. > If unchanged, call set_recommended_min_free_kbytes() to preserve > legacy watermark behavior. This avoids unnecessary khugepaged restarts. > > Tested with selftests ./run_kselftest.sh -t mm:ksft_thp.sh, > all test cases passed. > > Signed-off-by: Ran Xiaokai > --- Please keep my tags unless there are major logic changes. Thanks. Reviewed-by: Baolin Wang Tested-by: Baolin Wang > mm/shmem.c | 107 ++++++++++++++++++++++++++++++----------------------- > 1 file changed, 60 insertions(+), 47 deletions(-) > > diff --git a/mm/shmem.c b/mm/shmem.c > index 3b5dc21b323c..46d2cfc30823 100644 > --- a/mm/shmem.c > +++ b/mm/shmem.c > @@ -5526,6 +5526,29 @@ static ssize_t shmem_enabled_store(struct kobject *kobj, > struct kobj_attribute shmem_enabled_attr = __ATTR_RW(shmem_enabled); > static DEFINE_SPINLOCK(huge_shmem_orders_lock); > > +enum huge_shmem_enabled_mode { > + HUGE_SHMEM_ENABLED_ALWAYS = 0, > + HUGE_SHMEM_ENABLED_INHERIT, > + HUGE_SHMEM_ENABLED_WITHIN_SIZE, > + HUGE_SHMEM_ENABLED_ADVISE, > + HUGE_SHMEM_ENABLED_NEVER, > +}; > + > +static const char * const huge_shmem_enabled_mode_strings[] = { > + [HUGE_SHMEM_ENABLED_ALWAYS] = "always", > + [HUGE_SHMEM_ENABLED_INHERIT] = "inherit", > + [HUGE_SHMEM_ENABLED_WITHIN_SIZE] = "within_size", > + [HUGE_SHMEM_ENABLED_ADVISE] = "advise", > + [HUGE_SHMEM_ENABLED_NEVER] = "never", > +}; > + > +static unsigned long * const huge_shmem_orders_by_mode[] = { Nit: the name feels a bit verbose, how about huge_shmem_enabled_orders? (Perhaps David or Lorenzo has a better suggestion:))