stmmac: review private structure fields

recently many new supports have been added in the stmmac driver w/o taking care
about where each new field had to be placed inside the private structure for
guaranteeing the best cache usage.
This is what I wanted in the beginning, so this patch reorganizes all the fields
in order to keep adjacent fields for cache effect.
I have also tried to optimize them by using pahole.

V2: do not abuse with ____cacheline_aligned_in_smp and keep fields that
potentially could stay in the same cache-line for better usage in SMP systems.

Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
index 77d534a..c922fde 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
@@ -35,36 +35,45 @@
 
 struct stmmac_priv {
        /* Frequently used values are kept adjacent for cache effect */
-       struct dma_desc *dma_tx ____cacheline_aligned;  /* Basic TX desc */
-       struct dma_extended_desc *dma_etx;      /* Extended TX descriptor */
-       dma_addr_t dma_tx_phy;
+       struct dma_extended_desc *dma_etx ____cacheline_aligned_in_smp;
+       struct dma_desc *dma_tx;
        struct sk_buff **tx_skbuff;
-       dma_addr_t *tx_skbuff_dma;
        unsigned int cur_tx;
        unsigned int dirty_tx;
        unsigned int dma_tx_size;
+       u32 tx_count_frames;
+       u32 tx_coal_frames;
+       u32 tx_coal_timer;
+       dma_addr_t *tx_skbuff_dma;
+       dma_addr_t dma_tx_phy;
        int tx_coalesce;
+       int hwts_tx_en;
+       spinlock_t tx_lock;
+       bool tx_path_in_lpi_mode;
+       struct timer_list txtimer;
 
-       struct dma_desc *dma_rx;                /* Basic RX descriptor */
-       struct dma_extended_desc *dma_erx;      /* Extended RX descriptor */
+       struct dma_desc *dma_rx ____cacheline_aligned_in_smp;
+       struct dma_extended_desc *dma_erx;
+       struct sk_buff **rx_skbuff;
        unsigned int cur_rx;
        unsigned int dirty_rx;
-       struct sk_buff **rx_skbuff;
+       unsigned int dma_rx_size;
+       unsigned int dma_buf_sz;
+       u32 rx_riwt;
+       int hwts_rx_en;
        dma_addr_t *rx_skbuff_dma;
+       dma_addr_t dma_rx_phy;
 
+       struct napi_struct napi ____cacheline_aligned_in_smp;
+
+       void __iomem *ioaddr;
        struct net_device *dev;
-       dma_addr_t dma_rx_phy;
-       unsigned int dma_rx_size;
-       unsigned int dma_buf_sz;
        struct device *device;
        struct mac_device_info *hw;
-       void __iomem *ioaddr;
-
-       struct stmmac_extra_stats xstats;
-       struct napi_struct napi;
        int no_csum_insertion;
+       spinlock_t lock;
 
-       struct phy_device *phydev;
+       struct phy_device *phydev ____cacheline_aligned_in_smp;
        int oldlink;
        int speed;
        int oldduplex;
@@ -73,39 +82,30 @@ struct stmmac_priv {
        struct mii_bus *mii;
        int mii_irq[PHY_MAX_ADDR];
 
-       u32 msg_enable;
-       spinlock_t lock;
-       spinlock_t tx_lock;
-       int wolopts;
-       int wol_irq;
+       struct stmmac_extra_stats xstats ____cacheline_aligned_in_smp;
        struct plat_stmmacenet_data *plat;
-       struct stmmac_counters mmc;
        struct dma_features dma_cap;
+       struct stmmac_counters mmc;
        int hw_cap_support;
+       int synopsys_id;
+       u32 msg_enable;
+       int wolopts;
+       int wol_irq;
        struct clk *stmmac_clk;
        int clk_csr;
-       int synopsys_id;
        struct timer_list eee_ctrl_timer;
-       bool tx_path_in_lpi_mode;
        int lpi_irq;
        int eee_enabled;
        int eee_active;
        int tx_lpi_timer;
-       struct timer_list txtimer;
-       u32 tx_count_frames;
-       u32 tx_coal_frames;
-       u32 tx_coal_timer;
-       int use_riwt;
-       u32 rx_riwt;
+       int pcs;
        unsigned int mode;
        int extend_desc;
-       int pcs;
-       int hwts_tx_en;
-       int hwts_rx_en;
-       unsigned int default_addend;
-       u32 adv_ts;
        struct ptp_clock *ptp_clock;
        struct ptp_clock_info ptp_clock_ops;
+       unsigned int default_addend;
+       u32 adv_ts;
+       int use_riwt;
        spinlock_t ptp_lock;
 };