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Perez de Azpillaga" , Johannes Weiner Cc: Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Zi Yan , David Hildenbrand , Qi Zheng , Shakeel Butt , Lorenzo Stoakes , Kairui Song , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Baoquan He , Baolin Wang , JP Kobryn , Frank van der Linden , Thadeu Lima de Souza Cascardo , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20261104-kswapd-highatomic-unreserve-v1-1-38be5106adf5@kernel.org> <75540cfc-0577-4d91-9369-d1c4fe9c3096@gmail.com> From: "Vlastimil Babka (SUSE)" Content-Language: en-US Autocrypt: addr=vbabka@kernel.org; keydata= xsFNBFZdmxYBEADsw/SiUSjB0dM+vSh95UkgcHjzEVBlby/Fg+g42O7LAEkCYXi/vvq31JTB KxRWDHX0R2tgpFDXHnzZcQywawu8eSq0LxzxFNYMvtB7sV1pxYwej2qx9B75qW2plBs+7+YB 87tMFA+u+L4Z5xAzIimfLD5EKC56kJ1CsXlM8S/LHcmdD9Ctkn3trYDNnat0eoAcfPIP2OZ+ 9oe9IF/R28zmh0ifLXyJQQz5ofdj4bPf8ecEW0rhcqHfTD8k4yK0xxt3xW+6Exqp9n9bydiy tcSAw/TahjW6yrA+6JhSBv1v2tIm+itQc073zjSX8OFL51qQVzRFr7H2UQG33lw2QrvHRXqD Ot7ViKam7v0Ho9wEWiQOOZlHItOOXFphWb2yq3nzrKe45oWoSgkxKb97MVsQ+q2SYjJRBBH4 8qKhphADYxkIP6yut/eaj9ImvRUZZRi0DTc8xfnvHGTjKbJzC2xpFcY0DQbZzuwsIZ8OPJCc LM4S7mT25NE5kUTG/TKQCk922vRdGVMoLA7dIQrgXnRXtyT61sg8PG4wcfOnuWf8577aXP1x 6mzw3/jh3F+oSBHb/GcLC7mvWreJifUL2gEdssGfXhGWBo6zLS3qhgtwjay0Jl+kza1lo+Cv BB2T79D4WGdDuVa4eOrQ02TxqGN7G0Biz5ZLRSFzQSQwLn8fbwARAQABzSNWbGFzdGltaWwg QmFia2EgPHZiYWJrYUBrZXJuZWwub3JnPsLBsAQTAQoAWhYhBKlA1DSZLC6OmRA9UCJPp+fM gqZkBQJqFFy6GxSAAAAAAAQADm1hbnUyLDIuNSsxLjEyLDIsMgIbAwUJGtCBUAULCQgHAwUV CgkICwUWAgMBAAIeBQIXgAAKCRAiT6fnzIKmZJIUEADFx/tREzUImHrEwVHeSvDFmA7tJysI UVrlvrM09E7GIuzphzv7jYmo8n3ANpCczLEVr4G0syYQdTigaZgv3+FQDIIzhKih1IHhu1Ei XHlywNWKnQxxQEUNi5Mwx43wQz5XVw9F1A7gtKBKNtfogO511hAbrzagrYajyQacEJ/+sfhZ 9Da8ltHIXD8pcYaHUfQgEusCgmEd9+KrUwrTbckFKmYq5chuE6yJ4J0EmWknL096jIE6CnzF FRslQ3B1UKDjxVsm1ZHfir5NeWszLkTvGFsddFaWTgh8UycESG6VQzKXjjewXu2pG7YQYRpj QKm1W5X2TkwWkXRBZTmfmbhxIUMh3+zf5wQ463rSmDN/8v81tdqBtAW6rH/kzg1GvkaTHXn0 507yEHFzBksk2viAuIxxr7km8+/KARYLIdGtx30EG8cKzAUZOK6WqxtNCsXUJNrVE8CWrCaD icoNu7Fs1c5hmPHdSTnU48ce67449DdnO4neLSNhRiGlMHJgfJUmgrxu/hcYeOZ3haWmEQ2w uW1Mh01OHi8QZHCEyAbABrPs9GUgccc/4eYXX9hIgxfSkYzn8f+8NuIFPWl/0uTvjgqU29FQ SbzOLxHq9439Ox40G5mS5eZXRGxITYR+6TXvRGI6P/264jvflnr/pDGUttaikU+0W+1uxgKH cmYbEc7ATQRbGTU1AQgAn0H6UrFiWcovkh6EXVcl+SeqyO6JHOPm+e9Wu0Vw+VIUvXZVUVVQ La1PQDUi6j00ChlcR66g9/V0sPIcSutacPKfdKYOBvzd4rlhL8rfrdEsQw5ApZxrA8kYZVMh FmBRKAa6wos25moTlMKpCWzTH84+WO5+ziCTsTUZASAToz3RdunTD+vQcHj0GqNTPAHK63sf bAB2I0BslZkXkY1RLb/YhuA6E7JyEd2pilZOrIuBGl/5q2qSakgnAVFWFBR/DO27JuAksYnq +aH8vI0xGvwn75KqSk4UzAkDzWSmO4ZHuahKtQgZNsMYV+PGayRBX9b9zbldzopoLBdqHc4n jQARAQABwsF8BBgBCgAmAhsMFiEEqUDUNJksLo6ZED1QIk+n58yCpmQFAmfIHFQFCRYU6J8A CgkQIk+n58yCpmS2PA//bqN1LfcotmArgElsa+0EGZSQlYgK48pm8WAeTXTngudP9IJ4SuKY HR5RNjHcBeqN+Me0zxRqYzRb8nGanHEkDyf4Im8DQM8d6vbyU+FcPmG4skud4kgS1zMHnlVd SXfSIwKC/hKgdHG8aBV7545Lz9X6Iohea+94wneD0aw/hqF+QWewGZhWJriWAZtvEkzNjQOi 4U9F/trLten/x7bpphDSnDMKJtITbtzATT1Dq7o7VpIUK1nCTQALMuMjKCdi8OdU/+V+R3O4 0PXWvX8qrvqYapVbZ+9KqT74FsuB0Ya9uXwgBF2Q6cRuETZk5vqaqKxzqoQZCO8AOz/58j6O 2RHNy/mZEN+7tJ5Tsq42zVJ4jxsT8b9YplavCMsnBgDeRWhcbYhCyttoL7nYISyWg4kQYZ/P wIV3OuNv2f8iKYsxNsRuClOAF82+gvqOy1/1pprFjy8uo2pkoOrb63aOP3vO5VHnRKgra6dq NcaZ+c6J4H+nEJGi2SkHAUJz5oBzuThvPudLvPA/SK8sKoM01IRxSihev/S/5WLazXB1PGem OCbvzC1IjWJJraxiDJ5IygokapUa2RP7+WBR22skQ3SSl6G107QgWKSyTOGWEaRmV53vxQLV jXuCmzSSasTL60zq5yGrT4/DYQVSNEUiUbG4pYekxJujNeEDkUlky0Y= In-Reply-To: <75540cfc-0577-4d91-9369-d1c4fe9c3096@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 2ABA72000C X-Spam-Status: No, score=-7.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=4.0.1 X-Stat-Signature: brwqq8me1zjkbg46jxf6rg9m5kzs1xzx X-Rspam-User: X-HE-Tag: 1793865749-482099 X-HE-Meta: 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 3GsFVE04 368pBSsnhlZgunaITsaXyds69b7mE/zcJTj84N2G8tJsAGdp1NJ20UqiA8Ks+3nwWjv4NBV2QFiFtTbsSuBOGlbdZUg/+BtbV3mT+Rj82Pku8P3rUr2zZMn81LgqQzU0RSHSKfoUgvJRDzUUf29fU5caAmctGaHbWK1kmv080rp+TEpCRvVTLDOW+gWHNtav5/rukP+K88AdYvW0xolLB/o95VkG53piXJBLE+Rpq32C9rMckY05GNOTQTG2dIblrS3kI Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On 11/4/26 22:56, Jose A. Perez de Azpillaga wrote: > On 11/4/26 7:38 PM, Vlastimil Babka (SUSE) wrote: >> Hook this highatomic unreserve to the moment we are increasing kswapd >> reclaim priority, as that is when kswapd is struggling to make progress >> and it should roughly match the case of direct reclaim failure. >> > > isn't raise_priority true after almost every pass at DEF_PRIORITY, stuck > or not? Can you elaborate why? At least at first glance, kswapd_shrink_node() should return true if it scans the requested amount of pages. So I would assume that although balance_pgdat() will do multiple iterations to reach high watermarks (because every round of kswapd_shrink_node() will limit itself to SWAP_CLUSTER_MAX per zone for sc->nr_to_reclaim) this should not be raising priority if the rounds are successful? > [snip] > >> + if (raise_priority || !nr_reclaimed) { >> + /* >> + * Similarly to when direct reclaim is retrying, try to >> + * unreserve highatomic pageblocks on the node. Convert >> + * them to movable ones as kswapd doesn't have a target >> + * migratetype, and passing unmovable should lead to >> + * least permanent fragmentation. >> + */ >> + for (int i = 0; i <= highest_zoneidx; i++) { >> + struct zone *zone = pgdat->node_zones + i; >> + >> + unreserve_highatomic_pageblock_zone(zone, >> + MIGRATE_UNMOVABLE, false); >> + } > s/movable/unmovable/ in the comment? >