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charset=us-ascii Content-Disposition: inline In-Reply-To: <20240724190214.1108049-3-kinseyho@google.com> X-Stat-Signature: 817gixzkiqtz5q73bza1m4ou9rui7xks X-Rspamd-Queue-Id: 2FF02100009 X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1721940816-447352 X-HE-Meta: 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 F+yTDML+ XWsIE0WY0FAwcC0r2WTiVf/Tszh1oCK3EdQKhZhKF1J+z+HaWPGQM3tXedFJ9fYA2vCzz/G2tsFPYQOu3EX2hiUpJC1nq6/wEfY/lrBjbY5xzkrOzuoma0McG4oNYsAUql0gOjYnrQVeVyOXe7UtXrPVkErjbL5gMvxHPMCcn3D0sS4U9uLbJc8HLBmmYiZyIzRDsJjgReTRi8LxqGK7Ryoe2tT73oiam83dTny8cHsUeHLjdQZ9NEE+AyHh3EKDtuK/ud6IZ3vL96MQdOJR6WdHAO1BSUBGBmUEA1eo569DBngk8IlUL+A0nZKNPiK9sKo2C4USxVY4cz66YR0sA4noE9ZpfKNt3kNUuLB730sn+lV08wTv/blL50uDLYcYfwGnFWrdR64Sqyp2GV/9lF6wOgPLedfsdCr4PeiDu+7TvIfSP4uQV6w9X4lfSUAK22s+S7vCg0MMZO87jlb5hUy2RNqjBezjr7eOj X-Bogosity: Ham, tests=bogofilter, spamicity=0.000015, 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 Wed, Jul 24, 2024 at 07:02:12PM +0000, Kinsey Ho wrote: > The generation number in struct mem_cgroup_reclaim_iter should be > incremented on every round-trip. Currently, it is possible for a > concurrent reclaimer to jump in at the end of the hierarchy, causing a > traversal restart (resetting the iteration position) without > incrementing the generation number. > > Move the traversal restart such that the generation number is > incremented before the restart. > > Signed-off-by: Kinsey Ho The consequence of resetting the position without bumping the generation would be that another ongoing mem_cgroup_iter() could walk the tree twice, which is undesirable. It would be good to spell that out in the changelog. Otherwise, looks good to me. Acked-by: Johannes Weiner