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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.46.4 (3.46.4-1.fc37) MIME-Version: 1.0 X-Rspamd-Queue-Id: 802EC40030 X-Rspam-User: X-Stat-Signature: yr7sdt5zzkpehs45hx7fnkuy3r6rxw8r X-Rspamd-Server: rspam03 X-HE-Tag: 1696951195-156308 X-HE-Meta: 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 SznAfAS1 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 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 Tue, 2023-10-10 at 15:55 +0100, Matthew Wilcox (Oracle) wrote: > ilog2() rounds down, so for example when PowerPC 85xx sets > CONFIG_NR_CPUS > to 24, we will only allocate 4 bits to store the number of CPUs > instead > of 5.=C2=A0 Use bits_per() instead, which rounds up.=C2=A0 Found by code > inspection. > The effect of this would probably be a misaccounting when doing NUMA > balancing, so to a user, it would only be a performance penalty. > The effects may be more wide-spread; it's hard to tell. >=20 > Signed-off-by: Matthew Wilcox (Oracle) > Fixes: 90572890d202 ("mm: numa: Change page last {nid,pid} into > {cpu,pid}") > Cc: Peter Zijlstra > Cc: Mel Gorman > Cc: Ingo Molnar > Cc: Rik van Riel Reviewed-by: Rik van Riel --=20 All Rights Reversed.