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AJvYcCU7BkB3oS4TGRpOIuQbT9IB7DKvjagXIraFmPPmAQWwKtysOfMtr7WFzxREGAVFqsBkR7wuGy+XXg==@kvack.org X-Gm-Message-State: AOJu0Yzzn2mGdv/MAQODztK2aXKSadeosq4OAnj/luCNPgLaQBde3wIr INwufBQ0UzIag7HXrG48IupAtnfXo7Dv3t67WY+VIQ0TuMf2w6jo/BglmYeDxQOVoXJQ+kQPTUp DPhxQE7cHTw== X-Google-Smtp-Source: AGHT+IGpuYdMTwjODJHxm9TvUiZMzV7BQbJ6p7j9FK7Be3VAsZxuWpWRwZmRvOhYL3JCaQ6xUVBulyNCXtUOZg== X-Received: from wmbay15.prod.google.com ([2002:a05:600c:1e0f:b0:439:8e81:fd03]) (user=jackmanb job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:511e:b0:439:88bb:d017 with SMTP id 5b1f17b1804b1-439ae1d96e4mr108269225e9.6.1740400654949; Mon, 24 Feb 2025 04:37:34 -0800 (PST) Date: Mon, 24 Feb 2025 12:37:27 +0000 Mime-Version: 1.0 X-B4-Tracking: v=1; b=H4sIAAhovGcC/3XMQQ6DIBCF4auYWZeGIRi1q96jcUFxwEmoNGBMj eHupe67/F/yvgMyJaYMt+aARBtnjksNdWnAzmbxJHiqDUqqVirUwgaT2O0ir2SCcErrvpdao0W on3cix5/Te4y1Z85rTPvJb/hb/0kbChTdMNnWTA6f3XD3MfpAVxtfMJZSvkxDlumrAAAA X-Change-Id: 20250214-clarify-steal-f244880441c1 X-Mailer: b4 0.15-dev Message-ID: <20250224-clarify-steal-v2-0-be24da656764@google.com> Subject: [PATCH v2 0/2] mm/page_alloc: Some clarifications for migratetype fallback From: Brendan Jackman To: Andrew Morton Cc: Vlastimil Babka , Mel Gorman , Michal Hocko , Johannes Weiner , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Brendan Jackman , Yosry Ahmed X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 578B7A000C X-Stat-Signature: tthhnk9b1z6pjbeky1dyup4yqh7fb3gq X-HE-Tag: 1740400656-488642 X-HE-Meta: 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 OY4elaM+ 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000117, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: A couple of patches to try and make the code easier to follow. As discussed on the v1 thread [0] there are additional cleanups that can be done here, but Johannes is already working on those. These ones are just fiddling with the code to make it more readable, with no behavioural change. Note there's also a proposal from Vlastimil[1] to rework the interface which is renamed here to should_claim_block(), I have not adopted that suggestion yet but I could still be persuaded to do so. [0] https://lore.kernel.org/r/20250214-clarify-steal-v1-1-79dc5adf1b79@google.com [1] https://lore.kernel.org/all/764394d9-592c-4d68-8910-67362dd8810a@suse.cz/#t Signed-off-by: Brendan Jackman --- Changes in v2: - Tweaked some naming - Added clarifications of should_claim_block() - Link to v1: https://lore.kernel.org/r/20250214-clarify-steal-v1-1-79dc5adf1b79@google.com --- Brendan Jackman (2): mm/page_alloc: Clarify terminology in migratetype fallback code mm/page_alloc: Clarify should_claim_block() commentary mm/compaction.c | 4 +-- mm/internal.h | 2 +- mm/page_alloc.c | 88 ++++++++++++++++++++++++++++++--------------------------- 3 files changed, 50 insertions(+), 44 deletions(-) --- base-commit: 8df57ad4ed6209600ccd54db2357f75eb46408b6 change-id: 20250214-clarify-steal-f244880441c1 Best regards,