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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 1084140009 X-Stat-Signature: umhhhmg4soga89i8amdwfz5q1ia6zr89 X-Rspam-User: X-HE-Tag: 1707261500-692303 X-HE-Meta: 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 wlTV8ibC 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000096, 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 Tue, Feb 06, 2024 at 10:09:59AM -0800, Christoph Lameter (Ampere) wrote: > Can we get this merged for 6.9? The patch has been around for awhile now. > > > > Ampere Computing develops high end ARM processor that support an ever > increasing number of processors. The default 256 processors are > not enough for our newer products. The default is used by > distros and therefore our customers cannot use distro kernels because > the number of processors is not supported. > > One of the objections against earlier patches to increase the limit > was that the memory use becomes too high. There is a feature called > CPUMASK_OFFSTACK that configures the cpumasks in the kernel to be > dynamically allocated. This was used in the X86 architecture in the > past to enable support for larger CPU configurations up to 8k cpus. > > With that is becomes possible to dynamically size the allocation of > the cpu bitmaps depending on the quantity of processors detected on > bootup. > > This patch enables that logic if more than 256 processors > are configured and increases the default to 512 processors. > > Further increases may be needed if ARM processor vendors start > supporting more processors. Given the current inflationary trends > in core counts from multiple processor manufacturers this may occur. > > Tested-by: Eric Mackay Reviewed-by: Russell King (Oracle) Thanks! > Signed-off-by: Christoph Lameter (Ampere) -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!