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b=ML4vg+Og81CMlnLPvxVs5MrQVqYveAx2EOfh/vz8+WH982gQ4cOdmExulhZkEyb67 6sYPKIdUJXww6AoSUjAUgQd/9avs6hnBswbwhx/7EzRLDIvAM+lHf08TjVoCiV3oWK yyQSxT4rvZtEjS+XxRxCeEkyCHZ6S63bVV+pkXEWa7NH0F4SKWDhp3I9ni1RRt1r4m BVIw1ytGmJ5EmW5Yk+6DvmTGpobmnvrK3208l74upJzInwN1UYlrdzL5davJqxGkff IxrNmd7mlABoVWjVz/0q4tzReon4fotvSoaJiG0O4zizGDgUktuYyUPmKwbwUNK6cE k8ciaPyNs/YfQ== Message-ID: Date: Wed, 3 Jun 2026 12:00:38 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH mm-unstable v18 11/14] mm/khugepaged: Introduce mTHP collapse support To: Nico Pache Cc: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-trace-kernel@vger.kernel.org, aarcange@redhat.com, akpm@linux-foundation.org, anshuman.khandual@arm.com, apopple@nvidia.com, baohua@kernel.org, baolin.wang@linux.alibaba.com, byungchul@sk.com, catalin.marinas@arm.com, cl@gentwo.org, corbet@lwn.net, dave.hansen@linux.intel.com, dev.jain@arm.com, gourry@gourry.net, hannes@cmpxchg.org, hughd@google.com, jack@suse.cz, jackmanb@google.com, jannh@google.com, jglisse@google.com, joshua.hahnjy@gmail.com, kas@kernel.org, lance.yang@linux.dev, liam@infradead.org, ljs@kernel.org, mathieu.desnoyers@efficios.com, matthew.brost@intel.com, mhiramat@kernel.org, mhocko@suse.com, peterx@redhat.com, pfalcato@suse.de, rakie.kim@sk.com, raquini@redhat.com, rdunlap@infradead.org, richard.weiyang@gmail.com, rientjes@google.com, rostedt@goodmis.org, rppt@kernel.org, ryan.roberts@arm.com, shivankg@amd.com, sunnanyong@huawei.com, surenb@google.com, thomas.hellstrom@linux.intel.com, tiwai@suse.de, vbabka@suse.cz, vishal.moola@gmail.com, wangkefeng.wang@huawei.com, will@kernel.org, willy@infradead.org, yang@os.amperecomputing.com, ying.huang@linux.alibaba.com, ziy@nvidia.com, zokeefe@google.com, Usama Arif , usamaarif642@gmail.com References: <20260522150009.121603-1-npache@redhat.com> <20260522150009.121603-12-npache@redhat.com> <19639b08-5bf1-4974-9635-c458d512fa38@redhat.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam10 X-Rspam-User: X-Stat-Signature: fuxhfar9437n39xacryipzsesrcswxif X-Rspamd-Queue-Id: 315A140007 X-HE-Tag: 1780480855-39922 X-HE-Meta: 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 e/7sdiWx ptI9uR7ca03JEw9XLgELWh8Om91MSnHgb7zHbiSX0PzcPe5zTk4QJJh+AvlY4+HK2cUS1PME2umXU5SZD5Zo9CvwDpwKWGM9oflLt8B2s3avsmzXcuy+grMJZ8wqAQTOa3MbheB6YOVgfLAIpGVdg1jtcqTj1nOMA0XeIpDp9tZY7gEUmGCTJ3MVuEAMfgUhKgfKis+72kVVtmKt4MiKXCxDdcEeUinO+V/vg/3WJguO81saCcmdawXfDZr+tgvr4RK9T51y49A9f83GHJpGqw2i4ZYIJ1mTRs/NCGC3fQVcReAQgQN7v0qdbm+QyPjD5l1MRIKLBZtRVmew= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > next_order: > - if ((BIT(order) - 1) & enabled_orders) { > - const u8 next_order = order - 1; > - const u16 mid_offset = offset + (nr_ptes / 2); > - > - collapse_mthp_stack_push(cc, &stack_size, mid_offset, > - next_order); > - collapse_mthp_stack_push(cc, &stack_size, offset, > - next_order); > + if (order > KHUGEPAGED_MIN_MTHP_ORDER && > + (BIT(order) - 1) & enabled_orders) { Why not a test_bit() ? But, wouldn't you want to skip orders that are not enabled and try with the next smaller one in any case before you advance the offset? -- Cheers, David