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Howlett" Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Rick Edgecombe Subject: Re: [PATCH v2] mm/mmap: Regression fix for unmapped_area{_topdown} Message-Id: <20230414120957.d69f471ad9eb2a1d304a4146@linux-foundation.org> In-Reply-To: <20230414185919.4175572-1-Liam.Howlett@oracle.com> References: <20230414145728.4067069-3-Liam.Howlett@oracle.com> <20230414185919.4175572-1-Liam.Howlett@oracle.com> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Queue-Id: C1297180009 X-Rspamd-Server: rspam01 X-Stat-Signature: 555pxwmftahpu6jsy5c1tkunxyjr4d3c X-HE-Tag: 1681499399-621358 X-HE-Meta: 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 y9SSKO4E OMQzOq01EP4EzCHCHShrUrO6bePQC7Qe1pvJ1RAky4C6Lf6S6WvFPxodOu8V3SPvw+aFEGUo6pNhE+ahGElAqyxdOQ6Ca5M3KmW5x/2mPJLnMvUFhO2TEI56csamRJI8s6SVgh6GLpgvWio3ODZvPEQYmUN2zXeH2V16NC6Lr0o3csBL8g+oqt1ElQyooZDYqH7P7hGmzThw3JD/zPDhuX59i3mlZbw4P9u8yku7OnYcqJseqZqCdvVs0WFUd99sZDnubHCCuqgvjBLN0WgOg1qnrxUULWufNb6Bikf6PREYv/dCeL8NJG0rjF1IrZlOPiDK3AqLPUf3JNKo4RPqic8iVUuHRsiRoOpZJOC3et0F6Ggk9eXUYs9Tl1WcxS82OVnMJsexKtA7Lw6xJrtTXm+xABnY6tegf6h8I8QUC8tT5l3Gz5HzJxe+QlQ== 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: On Fri, 14 Apr 2023 14:59:19 -0400 "Liam R. Howlett" wrote: > The maple tree limits the gap returned to a window that specifically > fits what was asked. This may not be optimal in the case of switching > search directions or a gap that does not satisfy the requested space for > other reasons. Fix the search by retrying the operation and limiting > the search window in the rare occasion that a conflict occurs. This is a performance regression, yes? Of what magnitude?