From 730ff06d3f5cc2ce0348414b78c10528b767d4a3 Mon Sep 17 00:00:00 2001 From: Dipayaan Roy Date: Thu, 14 Aug 2025 07:04:10 -0700 Subject: net: mana: Use page pool fragments for RX buffers instead of full pages to improve memory efficiency. This patch enhances RX buffer handling in the mana driver by allocating pages from a page pool and slicing them into MTU-sized fragments, rather than dedicating a full page per packet. This approach is especially beneficial on systems with large base page sizes like 64KB. Key improvements: - Proper integration of page pool for RX buffer allocations. - MTU-sized buffer slicing to improve memory utilization. - Reduce overall per Rx queue memory footprint. - Automatic fallback to full-page buffers when: * Jumbo frames are enabled (MTU > PAGE_SIZE / 2). * The XDP path is active, to avoid complexities with fragment reuse. Testing on VMs with 64KB pages shows around 200% throughput improvement. Memory efficiency is significantly improved due to reduced wastage in page allocations. Example: We are now able to fit 35 rx buffers in a single 64kb page for MTU size of 1500, instead of 1 rx buffer per page previously. Tested: - iperf3, iperf2, and nttcp benchmarks. - Jumbo frames with MTU 9000. - Native XDP programs (XDP_PASS, XDP_DROP, XDP_TX, XDP_REDIRECT) for testing the XDP path in driver. - Memory leak detection (kmemleak). - Driver load/unload, reboot, and stress scenarios. Reviewed-by: Jacob Keller Reviewed-by: Saurabh Sengar Reviewed-by: Haiyang Zhang Signed-off-by: Dipayaan Roy Link: https://patch.msgid.link/20250814140410.GA22089@linuxonhyperv3.guj3yctzbm1etfxqx2vob5hsef.xx.internal.cloudapp.net Signed-off-by: Paolo Abeni --- include/net/mana/mana.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/net/mana') diff --git a/include/net/mana/mana.h b/include/net/mana/mana.h index e1030a7d2daa..0921485565c0 100644 --- a/include/net/mana/mana.h +++ b/include/net/mana/mana.h @@ -65,6 +65,8 @@ enum TRI_STATE { #define MANA_STATS_RX_COUNT 5 #define MANA_STATS_TX_COUNT 11 +#define MANA_RX_FRAG_ALIGNMENT 64 + struct mana_stats_rx { u64 packets; u64 bytes; @@ -328,6 +330,7 @@ struct mana_rxq { u32 datasize; u32 alloc_size; u32 headroom; + u32 frag_count; mana_handle_t rxobj; @@ -510,6 +513,7 @@ struct mana_port_context { u32 rxbpre_datasize; u32 rxbpre_alloc_size; u32 rxbpre_headroom; + u32 rxbpre_frag_count; struct bpf_prog *bpf_prog; -- cgit v1.2.3