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It can reduce the >> demands on DRAM bandwidth and reduces latency to the processor consuming >> the I/O data. > > This copy&pasted text found in cover letter and patch 1 and now here seems to be the > type of annoying repetitive text that Boris referred to [1]. Looking at this changelog > again it may also be confusing to start with introduction of one feature (SDCI), but > end with another SDCIAE. > > Here is a changelog that attempts to address issues, please feel free to improve: > > AMD's SDCIAE (SDCI Allocation Enforcement) PQE feature enables system software > to control the portions of L3 cache used for direct insertion of data from > I/O devices into the L3 cache. > > Introduce a generic resctrl cache resource property "io_alloc_capable" as the > first part of the new "io_alloc" resctrl feature that will support AMD's > SDCIAE. Any architecture can set a cache resource as "io_alloc_capable" if a > portion of the cache can be allocated for I/O traffic. > > Set the "io_alloc_capable" property for the L3 cache resource on x86 > (AMD) systems that support SDCIAE. > > Looks good. thank you. >> Introduce cache resource property "io_alloc_capable" that an architecture >> can set if a portion of the cache can be allocated for I/O traffic. >> >> Set this property on x86 systems that support SDCIAE (L3 Smart Data Cache >> Injection Allocation Enforcement). This property is set only for the L3 >> cache resource on systems that support SDCIAE. >> >> Signed-off-by: Babu Moger >> Reviewed-by: Reinette Chatre >> --- > > Reinette > > > [1] https://lore.kernel.org/lkml/20250911150850.GAaMLmAoi5fTIznQzY@fat_crate.local/ > >