From 237907c1ded8a1a447cea7c4f97ab853e8b46052 Mon Sep 17 00:00:00 2001 From: Eilon Greenstein Date: Wed, 14 Jan 2009 06:42:44 +0000 Subject: [PATCH] bnx2x: Barriers for the compiler To make sure no swapping are made by the compiler, changed HAS_WORK to inline functions and added all the necessary barriers Signed-off-by: Eilon Greenstein Signed-off-by: David S. Miller --- drivers/net/bnx2x.h | 9 +-------- drivers/net/bnx2x_main.c | 37 ++++++++++++++++++++++++++----------- 2 files changed, 27 insertions(+), 19 deletions(-) diff --git a/drivers/net/bnx2x.h b/drivers/net/bnx2x.h index 6fcccef..18f60aa 100644 --- a/drivers/net/bnx2x.h +++ b/drivers/net/bnx2x.h @@ -271,14 +271,7 @@ struct bnx2x_fastpath { #define bnx2x_fp(bp, nr, var) (bp->fp[nr].var) -#define BNX2X_HAS_TX_WORK(fp) \ - ((fp->tx_pkt_prod != le16_to_cpu(*fp->tx_cons_sb)) || \ - (fp->tx_pkt_prod != fp->tx_pkt_cons)) - -#define BNX2X_HAS_RX_WORK(fp) \ - (fp->rx_comp_cons != rx_cons_sb) - -#define BNX2X_HAS_WORK(fp) (BNX2X_HAS_RX_WORK(fp) || BNX2X_HAS_TX_WORK(fp)) +#define BNX2X_HAS_WORK(fp) (bnx2x_has_rx_work(fp) || bnx2x_has_tx_work(fp)) /* MC hsi */ diff --git a/drivers/net/bnx2x_main.c b/drivers/net/bnx2x_main.c index dc05e37..3236527 100644 --- a/drivers/net/bnx2x_main.c +++ b/drivers/net/bnx2x_main.c @@ -733,6 +733,17 @@ static u16 bnx2x_ack_int(struct bnx2x *bp) * fast path service functions */ +static inline int bnx2x_has_tx_work(struct bnx2x_fastpath *fp) +{ + u16 tx_cons_sb; + + /* Tell compiler that status block fields can change */ + barrier(); + tx_cons_sb = le16_to_cpu(*fp->tx_cons_sb); + return ((fp->tx_pkt_prod != tx_cons_sb) || + (fp->tx_pkt_prod != fp->tx_pkt_cons)); +} + /* free skb in the packet ring at pos idx * return idx of last bd freed */ @@ -6693,7 +6704,7 @@ static int bnx2x_nic_unload(struct bnx2x *bp, int unload_mode) cnt = 1000; smp_rmb(); - while (BNX2X_HAS_TX_WORK(fp)) { + while (bnx2x_has_tx_work(fp)) { bnx2x_tx_int(fp, 1000); if (!cnt) { @@ -9281,6 +9292,18 @@ static int bnx2x_set_power_state(struct bnx2x *bp, pci_power_t state) return 0; } +static inline int bnx2x_has_rx_work(struct bnx2x_fastpath *fp) +{ + u16 rx_cons_sb; + + /* Tell compiler that status block fields can change */ + barrier(); + rx_cons_sb = le16_to_cpu(*fp->rx_cons_sb); + if ((rx_cons_sb & MAX_RCQ_DESC_CNT) == MAX_RCQ_DESC_CNT) + rx_cons_sb++; + return (fp->rx_comp_cons != rx_cons_sb); +} + /* * net_device service functions */ @@ -9291,7 +9314,6 @@ static int bnx2x_poll(struct napi_struct *napi, int budget) napi); struct bnx2x *bp = fp->bp; int work_done = 0; - u16 rx_cons_sb; #ifdef BNX2X_STOP_ON_ERROR if (unlikely(bp->panic)) @@ -9304,19 +9326,12 @@ static int bnx2x_poll(struct napi_struct *napi, int budget) bnx2x_update_fpsb_idx(fp); - if (BNX2X_HAS_TX_WORK(fp)) + if (bnx2x_has_tx_work(fp)) bnx2x_tx_int(fp, budget); - rx_cons_sb = le16_to_cpu(*fp->rx_cons_sb); - if ((rx_cons_sb & MAX_RCQ_DESC_CNT) == MAX_RCQ_DESC_CNT) - rx_cons_sb++; - if (BNX2X_HAS_RX_WORK(fp)) + if (bnx2x_has_rx_work(fp)) work_done = bnx2x_rx_int(fp, budget); - rmb(); /* BNX2X_HAS_WORK() reads the status block */ - rx_cons_sb = le16_to_cpu(*fp->rx_cons_sb); - if ((rx_cons_sb & MAX_RCQ_DESC_CNT) == MAX_RCQ_DESC_CNT) - rx_cons_sb++; /* must not complete if we consumed full budget */ if ((work_done < budget) && !BNX2X_HAS_WORK(fp)) { -- 2.7.4