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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Action: no action X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: B4618A0007 X-Stat-Signature: dc8kxujjtme9or38j8muc1dkpztu5k5i X-HE-Tag: 1756405892-657195 X-HE-Meta: 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 7jER0/2h Pok3VK0gmi3qHcY5Dx0HKJ+593heaR0pY0URt56iHP62Cghs1VqhML5Qa1yOELfRfzncooOKwT+A9OX+pugZsietgqayRGh4gHl2eF6s2y1Sgs2fNwkGF4fcO4pyQt8YabwzB4CIp7TzOCBbgMck7bB3VGocpyB2qsL4Li46LTDeyJ/DSRzFkDHaFtY5O4fHdoAL5UHJWXeIMPwpuTCRhbrcn6TE9vyhUu0WuJdoktUGi1h96/3yP/H9NFruQI5XSpnsCC7cLrvKZ6h9SdrQEEYoBQdWzPqgSch9Di4OeFZONZV9ncrwcm1z/yWIKrEzgpOZBPnoCOTOTlG3gQ6sHMIQfnvynBFGUULli 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 8/27/25 17:30, Brendan Jackman wrote: > On Wed Aug 27, 2025 at 2:13 AM UTC, Andrew Morton wrote: >> On Tue, 26 Aug 2025 14:06:54 +0000 Brendan Jackman wrote: >> >>> Currently order is signed in one version of the function and unsigned in >>> the other. Tidy that up. >>> >>> In page_alloc.c, order is unsigned in the vast majority of cases. But, >>> there is a cluster of exceptions in compaction-related code (probably >>> stemming from the fact that compact_control.order is signed). So, prefer >>> local consistency and make this one signed too. >>> >> >> grumble, pet peeve. Negative orders make no sense. Can we make >> cc->order unsigned in order (heh) to make everything nice? > > I think we can't "just" do that: That part should be easy to convert to a compact_control flag. Zi's point about going negative seems like more prone to overlook some case. But worth trying and the cleanups I'd say. > /* > * order == -1 is expected when compacting proactively via > * 1. /proc/sys/vm/compact_memory > * 2. /sys/devices/system/node/nodex/compact > * 3. /proc/sys/vm/compaction_proactiveness > */ > static inline bool is_via_compact_memory(int order) > { > return order == -1; > }