From: Rosen Penev Date: Mon, 4 Dec 2017 19:40:23 +0000 (-0800) Subject: ag71xx: Reorder ag71xx struct members for better cache performance X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=4e03a742e0e59a0b996196500d06bb72ff224c02;p=openwrt%2Fstaging%2Fadrian.git ag71xx: Reorder ag71xx struct members for better cache performance Qualcomm claims this improves the D-cache footprint. Origina commit message below: From: Ben Menchaca Date: Fri, 7 Jun 2013 10:57:28 -0500 Subject: [ag71xx] cluster/align structs for cache perf Cluster the frequently used, per-packet structures in ag71xx near to each other, and cacheline-align them. Some other re-ordering occurred to move "warmer" structures near the per-packet structures. Signed-off-by: Ben Menchaca Signed-off-by: Rosen Penev --- diff --git a/target/linux/ar71xx/files/drivers/net/ethernet/atheros/ag71xx/ag71xx.h b/target/linux/ar71xx/files/drivers/net/ethernet/atheros/ag71xx/ag71xx.h index a712812916..5ead6b316a 100644 --- a/target/linux/ar71xx/files/drivers/net/ethernet/atheros/ag71xx/ag71xx.h +++ b/target/linux/ar71xx/files/drivers/net/ethernet/atheros/ag71xx/ag71xx.h @@ -153,20 +153,31 @@ struct ag71xx_debug { }; struct ag71xx { - void __iomem *mac_base; + /* + * Critical data related to the per-packet data path are clustered + * early in this structure to help improve the D-cache footprint. + */ + struct ag71xx_ring rx_ring ____cacheline_aligned; + struct ag71xx_ring tx_ring ____cacheline_aligned; + + unsigned int max_frame_len; + unsigned int desc_pktlen_mask; + unsigned int rx_buf_size; - spinlock_t lock; - struct platform_device *pdev; struct net_device *dev; + struct platform_device *pdev; + spinlock_t lock; struct napi_struct napi; u32 msg_enable; + /* + * From this point onwards we're not looking at per-packet fields. + */ + void __iomem *mac_base; + struct ag71xx_desc *stop_desc; dma_addr_t stop_desc_dma; - struct ag71xx_ring rx_ring; - struct ag71xx_ring tx_ring; - struct mii_bus *mii_bus; struct phy_device *phy_dev; void *phy_priv; @@ -175,10 +186,6 @@ struct ag71xx { unsigned int speed; int duplex; - unsigned int max_frame_len; - unsigned int desc_pktlen_mask; - unsigned int rx_buf_size; - struct delayed_work restart_work; struct delayed_work link_work; struct timer_list oom_timer;