From: Jakub Kicinski Date: Sat, 2 May 2026 02:02:09 +0000 (-0700) Subject: Merge branch 'net-mlx5-enable-sub-page-allocations-for-mlx5_frag_buf' X-Git-Url: http://git.ipfire.org/gitweb/index.cgi?a=commitdiff_plain;h=0f19519fdd22bc0f5429377da3a52327c5eee166;p=thirdparty%2Fkernel%2Flinux.git Merge branch 'net-mlx5-enable-sub-page-allocations-for-mlx5_frag_buf' Tariq Toukan says: ==================== net/mlx5: enable sub-page allocations for mlx5_frag_buf This series aims to improve memory utilization for DMA-coherent fragmented-buffer allocations on systems with large PAGE_SIZE. Before this change, such allocations were page-granular, as they were backed by full pages. On large-page systems this caused significant internal waste for small objects. For example, a single 4K request consumed an entire 64K page. The common kernel solution for sub-page coherent DMA allocations is the DMA pool API. However, those pools do not return pages to the system until teardown. That behavior is not a good fit for mlx5_frag_buf allocations, since they back interface resources (WQs and CQs). Interfaces may be removed dynamically, so their memory footprint should reflect live usage to avoid situations where large amounts of memory remain tied up in pools. This series introduces a lightweight mlx5-local pool implementation for sub-page coherent DMA allocations, which immediately returns free backing pages. It wires mlx5_frag_buf allocations to use these internal pools, while keeping the mechanism reusable for other mlx5-internal coherent DMA allocation users in follow-up work. ==================== Link: https://patch.msgid.link/20260429201429.223809-1-tariqt@nvidia.com Signed-off-by: Jakub Kicinski --- 0f19519fdd22bc0f5429377da3a52327c5eee166