Skip to content

Commit

Permalink
bna: tx rx cleanup fix
Browse files Browse the repository at this point in the history 
This patch removes busy wait in tx/rx cleanup. bnad_cb_tx_cleanup() and
bnad_cb_rx_cleanup() functions are called from irq context, and currently
they do busy wait for the in-flight transmit or the currently executing napi
polling routine to complete. To fix the issue, we create a workqueue to defer
tx & rx cleanup processing, an in the tx rx cleanup handler, we will
wait respective in flight processing to complete, before freeing the buffers.

Signed-off-by: Jing Huang <huangj@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
  • Loading branch information
Jing Huang authored and David S. Miller committed Apr 4, 2012
1 parent f96c1d2 commit 01b54b1
Show file tree
Hide file tree
Showing 2 changed files with 125 additions and 80 deletions.
201 changes: 121 additions & 80 deletions drivers/net/ethernet/brocade/bna/bnad.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -80,8 +80,6 @@ do { \
(sizeof(struct bnad_skb_unmap) * ((_depth) - 1)); \
} while (0)

#define BNAD_TXRX_SYNC_MDELAY 250 /* 250 msecs */

static void
bnad_add_to_list(struct bnad *bnad)
{
Expand Down Expand Up @@ -141,7 +139,8 @@ bnad_pci_unmap_skb(struct device *pdev, struct bnad_skb_unmap *array,

for (j = 0; j < frag; j++) {
dma_unmap_page(pdev, dma_unmap_addr(&array[index], dma_addr),
skb_frag_size(&skb_shinfo(skb)->frags[j]), DMA_TO_DEVICE);
skb_frag_size(&skb_shinfo(skb)->frags[j]),
DMA_TO_DEVICE);
dma_unmap_addr_set(&array[index], dma_addr, 0);
BNA_QE_INDX_ADD(index, 1, depth);
}
Expand Down Expand Up @@ -453,12 +452,8 @@ bnad_poll_cq(struct bnad *bnad, struct bna_ccb *ccb, int budget)
struct bna_pkt_rate *pkt_rt = &ccb->pkt_rate;
struct bnad_rx_ctrl *rx_ctrl = (struct bnad_rx_ctrl *)(ccb->ctrl);

set_bit(BNAD_FP_IN_RX_PATH, &rx_ctrl->flags);

if (!test_bit(BNAD_RXQ_STARTED, &ccb->rcb[0]->flags)) {
clear_bit(BNAD_FP_IN_RX_PATH, &rx_ctrl->flags);
if (!test_bit(BNAD_RXQ_STARTED, &ccb->rcb[0]->flags))
return 0;
}

prefetch(bnad->netdev);
BNA_CQ_QPGE_PTR_GET(ccb->producer_index, ccb->sw_qpt, cmpl,
Expand Down Expand Up @@ -533,9 +528,8 @@ bnad_poll_cq(struct bnad *bnad, struct bna_ccb *ccb, int budget)

if (skb->ip_summed == CHECKSUM_UNNECESSARY)
napi_gro_receive(&rx_ctrl->napi, skb);
else {
else
netif_receive_skb(skb);
}

next:
cmpl->valid = 0;
Expand Down Expand Up @@ -839,20 +833,9 @@ bnad_cb_tcb_destroy(struct bnad *bnad, struct bna_tcb *tcb)
{
struct bnad_tx_info *tx_info =
(struct bnad_tx_info *)tcb->txq->tx->priv;
struct bnad_unmap_q *unmap_q = tcb->unmap_q;

while (test_and_set_bit(BNAD_TXQ_FREE_SENT, &tcb->flags))
cpu_relax();

bnad_free_all_txbufs(bnad, tcb);

unmap_q->producer_index = 0;
unmap_q->consumer_index = 0;

smp_mb__before_clear_bit();
clear_bit(BNAD_TXQ_FREE_SENT, &tcb->flags);

tx_info->tcb[tcb->id] = NULL;
tcb->priv = NULL;
}

static void
Expand All @@ -865,12 +848,6 @@ bnad_cb_rcb_setup(struct bnad *bnad, struct bna_rcb *rcb)
unmap_q->q_depth = BNAD_RX_UNMAPQ_DEPTH;
}

static void
bnad_cb_rcb_destroy(struct bnad *bnad, struct bna_rcb *rcb)
{
bnad_free_all_rxbufs(bnad, rcb);
}

static void
bnad_cb_ccb_setup(struct bnad *bnad, struct bna_ccb *ccb)
{
Expand Down Expand Up @@ -916,7 +893,6 @@ bnad_cb_tx_resume(struct bnad *bnad, struct bna_tx *tx)
{
struct bnad_tx_info *tx_info = (struct bnad_tx_info *)tx->priv;
struct bna_tcb *tcb;
struct bnad_unmap_q *unmap_q;
u32 txq_id;
int i;

Expand All @@ -926,23 +902,9 @@ bnad_cb_tx_resume(struct bnad *bnad, struct bna_tx *tx)
continue;
txq_id = tcb->id;

unmap_q = tcb->unmap_q;

if (test_bit(BNAD_TXQ_TX_STARTED, &tcb->flags))
continue;

while (test_and_set_bit(BNAD_TXQ_FREE_SENT, &tcb->flags))
cpu_relax();

bnad_free_all_txbufs(bnad, tcb);

unmap_q->producer_index = 0;
unmap_q->consumer_index = 0;

smp_mb__before_clear_bit();
clear_bit(BNAD_TXQ_FREE_SENT, &tcb->flags);

BUG_ON(test_bit(BNAD_TXQ_TX_STARTED, &tcb->flags));
set_bit(BNAD_TXQ_TX_STARTED, &tcb->flags);
BUG_ON(*(tcb->hw_consumer_index) != 0);

if (netif_carrier_ok(bnad->netdev)) {
printk(KERN_INFO "bna: %s %d TXQ_STARTED\n",
Expand All @@ -963,6 +925,54 @@ bnad_cb_tx_resume(struct bnad *bnad, struct bna_tx *tx)
}
}

/*
* Free all TxQs buffers and then notify TX_E_CLEANUP_DONE to Tx fsm.
*/
static void
bnad_tx_cleanup(struct delayed_work *work)
{
struct bnad_tx_info *tx_info =
container_of(work, struct bnad_tx_info, tx_cleanup_work);
struct bnad *bnad = NULL;
struct bnad_unmap_q *unmap_q;
struct bna_tcb *tcb;
unsigned long flags;
uint32_t i, pending = 0;

for (i = 0; i < BNAD_MAX_TXQ_PER_TX; i++) {
tcb = tx_info->tcb[i];
if (!tcb)
continue;

bnad = tcb->bnad;

if (test_and_set_bit(BNAD_TXQ_FREE_SENT, &tcb->flags)) {
pending++;
continue;
}

bnad_free_all_txbufs(bnad, tcb);

unmap_q = tcb->unmap_q;
unmap_q->producer_index = 0;
unmap_q->consumer_index = 0;

smp_mb__before_clear_bit();
clear_bit(BNAD_TXQ_FREE_SENT, &tcb->flags);
}

if (pending) {
queue_delayed_work(bnad->work_q, &tx_info->tx_cleanup_work,
msecs_to_jiffies(1));
return;
}

spin_lock_irqsave(&bnad->bna_lock, flags);
bna_tx_cleanup_complete(tx_info->tx);
spin_unlock_irqrestore(&bnad->bna_lock, flags);
}


static void
bnad_cb_tx_cleanup(struct bnad *bnad, struct bna_tx *tx)
{
Expand All @@ -976,8 +986,7 @@ bnad_cb_tx_cleanup(struct bnad *bnad, struct bna_tx *tx)
continue;
}

mdelay(BNAD_TXRX_SYNC_MDELAY);
bna_tx_cleanup_complete(tx);
queue_delayed_work(bnad->work_q, &tx_info->tx_cleanup_work, 0);
}

static void
Expand All @@ -1001,6 +1010,44 @@ bnad_cb_rx_stall(struct bnad *bnad, struct bna_rx *rx)
}
}

/*
* Free all RxQs buffers and then notify RX_E_CLEANUP_DONE to Rx fsm.
*/
static void
bnad_rx_cleanup(void *work)
{
struct bnad_rx_info *rx_info =
container_of(work, struct bnad_rx_info, rx_cleanup_work);
struct bnad_rx_ctrl *rx_ctrl;
struct bnad *bnad = NULL;
unsigned long flags;
uint32_t i;

for (i = 0; i < BNAD_MAX_RXP_PER_RX; i++) {
rx_ctrl = &rx_info->rx_ctrl[i];

if (!rx_ctrl->ccb)
continue;

bnad = rx_ctrl->ccb->bnad;

/*
* Wait till the poll handler has exited
* and nothing can be scheduled anymore
*/
napi_disable(&rx_ctrl->napi);

bnad_cq_cmpl_init(bnad, rx_ctrl->ccb);
bnad_free_all_rxbufs(bnad, rx_ctrl->ccb->rcb[0]);
if (rx_ctrl->ccb->rcb[1])
bnad_free_all_rxbufs(bnad, rx_ctrl->ccb->rcb[1]);
}

spin_lock_irqsave(&bnad->bna_lock, flags);
bna_rx_cleanup_complete(rx_info->rx);
spin_unlock_irqrestore(&bnad->bna_lock, flags);
}

static void
bnad_cb_rx_cleanup(struct bnad *bnad, struct bna_rx *rx)
{
Expand All @@ -1009,8 +1056,6 @@ bnad_cb_rx_cleanup(struct bnad *bnad, struct bna_rx *rx)
struct bnad_rx_ctrl *rx_ctrl;
int i;

mdelay(BNAD_TXRX_SYNC_MDELAY);

for (i = 0; i < BNAD_MAX_RXP_PER_RX; i++) {
rx_ctrl = &rx_info->rx_ctrl[i];
ccb = rx_ctrl->ccb;
Expand All @@ -1021,12 +1066,9 @@ bnad_cb_rx_cleanup(struct bnad *bnad, struct bna_rx *rx)

if (ccb->rcb[1])
clear_bit(BNAD_RXQ_STARTED, &ccb->rcb[1]->flags);

while (test_bit(BNAD_FP_IN_RX_PATH, &rx_ctrl->flags))
cpu_relax();
}

bna_rx_cleanup_complete(rx);
queue_work(bnad->work_q, &rx_info->rx_cleanup_work);
}

static void
Expand All @@ -1046,13 +1088,12 @@ bnad_cb_rx_post(struct bnad *bnad, struct bna_rx *rx)
if (!ccb)
continue;

bnad_cq_cmpl_init(bnad, ccb);
napi_enable(&rx_ctrl->napi);

for (j = 0; j < BNAD_MAX_RXQ_PER_RXP; j++) {
rcb = ccb->rcb[j];
if (!rcb)
continue;
bnad_free_all_rxbufs(bnad, rcb);

set_bit(BNAD_RXQ_STARTED, &rcb->flags);
set_bit(BNAD_RXQ_POST_OK, &rcb->flags);
Expand Down Expand Up @@ -1704,7 +1745,7 @@ bnad_napi_poll_rx(struct napi_struct *napi, int budget)

#define BNAD_NAPI_POLL_QUOTA 64
static void
bnad_napi_init(struct bnad *bnad, u32 rx_id)
bnad_napi_add(struct bnad *bnad, u32 rx_id)
{
struct bnad_rx_ctrl *rx_ctrl;
int i;
Expand All @@ -1718,29 +1759,13 @@ bnad_napi_init(struct bnad *bnad, u32 rx_id)
}

static void
bnad_napi_enable(struct bnad *bnad, u32 rx_id)
{
struct bnad_rx_ctrl *rx_ctrl;
int i;

/* Initialize & enable NAPI */
for (i = 0; i < bnad->num_rxp_per_rx; i++) {
rx_ctrl = &bnad->rx_info[rx_id].rx_ctrl[i];

napi_enable(&rx_ctrl->napi);
}
}

static void
bnad_napi_disable(struct bnad *bnad, u32 rx_id)
bnad_napi_delete(struct bnad *bnad, u32 rx_id)
{
int i;

/* First disable and then clean up */
for (i = 0; i < bnad->num_rxp_per_rx; i++) {
napi_disable(&bnad->rx_info[rx_id].rx_ctrl[i].napi);
for (i = 0; i < bnad->num_rxp_per_rx; i++)
netif_napi_del(&bnad->rx_info[rx_id].rx_ctrl[i].napi);
}
}

/* Should be held with conf_lock held */
Expand Down Expand Up @@ -1832,6 +1857,9 @@ bnad_setup_tx(struct bnad *bnad, u32 tx_id)
goto err_return;
tx_info->tx = tx;

INIT_DELAYED_WORK(&tx_info->tx_cleanup_work,
(work_func_t)bnad_tx_cleanup);

/* Register ISR for the Tx object */
if (intr_info->intr_type == BNA_INTR_T_MSIX) {
err = bnad_tx_msix_register(bnad, tx_info,
Expand Down Expand Up @@ -1928,7 +1956,7 @@ bnad_cleanup_rx(struct bnad *bnad, u32 rx_id)
if (rx_info->rx_ctrl[0].ccb->intr_type == BNA_INTR_T_MSIX)
bnad_rx_msix_unregister(bnad, rx_info, rx_config->num_paths);

bnad_napi_disable(bnad, rx_id);
bnad_napi_delete(bnad, rx_id);

spin_lock_irqsave(&bnad->bna_lock, flags);
bna_rx_destroy(rx_info->rx);
Expand All @@ -1952,7 +1980,7 @@ bnad_setup_rx(struct bnad *bnad, u32 rx_id)
struct bna_rx_config *rx_config = &bnad->rx_config[rx_id];
static const struct bna_rx_event_cbfn rx_cbfn = {
.rcb_setup_cbfn = bnad_cb_rcb_setup,
.rcb_destroy_cbfn = bnad_cb_rcb_destroy,
.rcb_destroy_cbfn = NULL,
.ccb_setup_cbfn = bnad_cb_ccb_setup,
.ccb_destroy_cbfn = bnad_cb_ccb_destroy,
.rx_stall_cbfn = bnad_cb_rx_stall,
Expand Down Expand Up @@ -1998,11 +2026,14 @@ bnad_setup_rx(struct bnad *bnad, u32 rx_id)
rx_info->rx = rx;
spin_unlock_irqrestore(&bnad->bna_lock, flags);

INIT_WORK(&rx_info->rx_cleanup_work,
(work_func_t)(bnad_rx_cleanup));

/*
* Init NAPI, so that state is set to NAPI_STATE_SCHED,
* so that IRQ handler cannot schedule NAPI at this point.
*/
bnad_napi_init(bnad, rx_id);
bnad_napi_add(bnad, rx_id);

/* Register ISR for the Rx object */
if (intr_info->intr_type == BNA_INTR_T_MSIX) {
Expand All @@ -2028,9 +2059,6 @@ bnad_setup_rx(struct bnad *bnad, u32 rx_id)
bna_rx_enable(rx);
spin_unlock_irqrestore(&bnad->bna_lock, flags);

/* Enable scheduling of NAPI */
bnad_napi_enable(bnad, rx_id);

return 0;

err_return:
Expand Down Expand Up @@ -3129,6 +3157,7 @@ bnad_netdev_init(struct bnad *bnad, bool using_dac)
* 2. Setup netdev pointer in pci_dev
* 3. Initialze Tx free tasklet
* 4. Initialize no. of TxQ & CQs & MSIX vectors
* 5. Initialize work queue.
*/
static int
bnad_init(struct bnad *bnad,
Expand Down Expand Up @@ -3174,6 +3203,12 @@ bnad_init(struct bnad *bnad,
tasklet_init(&bnad->tx_free_tasklet, bnad_tx_free_tasklet,
(unsigned long)bnad);

sprintf(bnad->wq_name, "%s_wq_%d", BNAD_NAME, bnad->id);
bnad->work_q = create_singlethread_workqueue(bnad->wq_name);

if (!bnad->work_q)
return -ENOMEM;

return 0;
}

Expand All @@ -3185,6 +3220,12 @@ bnad_init(struct bnad *bnad,
static void
bnad_uninit(struct bnad *bnad)
{
if (bnad->work_q) {
flush_workqueue(bnad->work_q);
destroy_workqueue(bnad->work_q);
bnad->work_q = NULL;
}

if (bnad->bar0)
iounmap(bnad->bar0);
pci_set_drvdata(bnad->pcidev, NULL);
Expand Down
Loading

0 comments on commit 01b54b1

Please sign in to comment.