* Max number of Tx descriptors we clean up at a time. Should be modest as
* freeing skbs isn't cheap and it happens while holding locks. We just need
* to free packets faster than they arrive, we eventually catch up and keep
- * the amortized cost reasonable. Must be >= 2 * TXQ_STOP_THRES.
+ * the amortized cost reasonable. Must be >= 2 * TXQ_STOP_THRES. It should
+ * also match the CIDX Flush Threshold.
*/
-#define MAX_TX_RECLAIM 16
+#define MAX_TX_RECLAIM 32
/*
* Max number of Rx buffers we replenish at a time. Again keep this modest,
}
/**
- * cxgb4_reclaim_completed_tx - reclaims completed Tx descriptors
+ * reclaim_completed_tx - reclaims completed TX Descriptors
* @adap: the adapter
* @q: the Tx queue to reclaim completed descriptors from
+ * @maxreclaim: the maximum number of TX Descriptors to reclaim or -1
* @unmap: whether the buffers should be unmapped for DMA
*
- * Reclaims Tx descriptors that the SGE has indicated it has processed,
- * and frees the associated buffers if possible. Called with the Tx
- * queue locked.
+ * Reclaims Tx Descriptors that the SGE has indicated it has processed,
+ * and frees the associated buffers if possible. If @max == -1, then
+ * we'll use a defaiult maximum. Called with the TX Queue locked.
*/
-inline void cxgb4_reclaim_completed_tx(struct adapter *adap, struct sge_txq *q,
- bool unmap)
+static inline int reclaim_completed_tx(struct adapter *adap, struct sge_txq *q,
+ int maxreclaim, bool unmap)
{
- int avail = reclaimable(q);
+ int reclaim = reclaimable(q);
- if (avail) {
+ if (reclaim) {
/*
* Limit the amount of clean up work we do at a time to keep
* the Tx lock hold time O(1).
*/
- if (avail > MAX_TX_RECLAIM)
- avail = MAX_TX_RECLAIM;
+ if (maxreclaim < 0)
+ maxreclaim = MAX_TX_RECLAIM;
+ if (reclaim > maxreclaim)
+ reclaim = maxreclaim;
- free_tx_desc(adap, q, avail, unmap);
- q->in_use -= avail;
+ free_tx_desc(adap, q, reclaim, unmap);
+ q->in_use -= reclaim;
}
+
+ return reclaim;
+}
+
+/**
+ * cxgb4_reclaim_completed_tx - reclaims completed Tx descriptors
+ * @adap: the adapter
+ * @q: the Tx queue to reclaim completed descriptors from
+ * @unmap: whether the buffers should be unmapped for DMA
+ *
+ * Reclaims Tx descriptors that the SGE has indicated it has processed,
+ * and frees the associated buffers if possible. Called with the Tx
+ * queue locked.
+ */
+void cxgb4_reclaim_completed_tx(struct adapter *adap, struct sge_txq *q,
+ bool unmap)
+{
+ (void)reclaim_completed_tx(adap, q, -1, unmap);
}
EXPORT_SYMBOL(cxgb4_reclaim_completed_tx);
}
/**
+ * t4_sge_eth_txq_egress_update - handle Ethernet TX Queue update
+ * @adap: the adapter
+ * @eq: the Ethernet TX Queue
+ * @maxreclaim: the maximum number of TX Descriptors to reclaim or -1
+ *
+ * We're typically called here to update the state of an Ethernet TX
+ * Queue with respect to the hardware's progress in consuming the TX
+ * Work Requests that we've put on that Egress Queue. This happens
+ * when we get Egress Queue Update messages and also prophylactically
+ * in regular timer-based Ethernet TX Queue maintenance.
+ */
+int t4_sge_eth_txq_egress_update(struct adapter *adap, struct sge_eth_txq *eq,
+ int maxreclaim)
+{
+ struct sge_txq *q = &eq->q;
+ unsigned int reclaimed;
+
+ if (!q->in_use || !__netif_tx_trylock(eq->txq))
+ return 0;
+
+ /* Reclaim pending completed TX Descriptors. */
+ reclaimed = reclaim_completed_tx(adap, &eq->q, maxreclaim, true);
+
+ /* If the TX Queue is currently stopped and there's now more than half
+ * the queue available, restart it. Otherwise bail out since the rest
+ * of what we want do here is with the possibility of shipping any
+ * currently buffered Coalesced TX Work Request.
+ */
+ if (netif_tx_queue_stopped(eq->txq) && txq_avail(q) > (q->size / 2)) {
+ netif_tx_wake_queue(eq->txq);
+ eq->q.restarts++;
+ }
+
+ __netif_tx_unlock(eq->txq);
+ return reclaimed;
+}
+
+/**
* cxgb4_eth_xmit - add a packet to an Ethernet Tx queue
* @skb: the packet
* @dev: the egress net device
}
skb_tx_timestamp(skb);
- cxgb4_reclaim_completed_tx(adap, &q->q, true);
+ reclaim_completed_tx(adap, &q->q, -1, true);
cntrl = TXPKT_L4CSUM_DIS_F | TXPKT_IPCSUM_DIS_F;
#ifdef CONFIG_CHELSIO_T4_FCOE
wr_mid = FW_WR_LEN16_V(DIV_ROUND_UP(flits, 2));
if (unlikely(credits < ETHTXQ_STOP_THRES)) {
+ /* After we're done injecting the Work Request for this
+ * packet, we'll be below our "stop threshold" so stop the TX
+ * Queue now and schedule a request for an SGE Egress Queue
+ * Update message. The queue will get started later on when
+ * the firmware processes this Work Request and sends us an
+ * Egress Queue Status Update message indicating that space
+ * has opened up.
+ */
eth_txq_stop(q);
- wr_mid |= FW_WR_EQUEQ_F | FW_WR_EQUIQ_F;
+
+ /* If we're using the SGE Doorbell Queue Timer facility, we
+ * don't need to ask the Firmware to send us Egress Queue CIDX
+ * Updates: the Hardware will do this automatically. And
+ * since we send the Ingress Queue CIDX Updates to the
+ * corresponding Ethernet Response Queue, we'll get them very
+ * quickly.
+ */
+ if (!q->dbqt)
+ wr_mid |= FW_WR_EQUEQ_F | FW_WR_EQUIQ_F;
}
wr = (void *)&q->q.desc[q->q.pidx];
/* Take this opportunity to reclaim any TX Descriptors whose DMA
* transfers have completed.
*/
- cxgb4_reclaim_completed_tx(adapter, &txq->q, true);
+ reclaim_completed_tx(adapter, &txq->q, -1, true);
/* Calculate the number of flits and TX Descriptors we're going to
* need along with how many TX Descriptors will be left over after
* has opened up.
*/
eth_txq_stop(txq);
- wr_mid |= FW_WR_EQUEQ_F | FW_WR_EQUIQ_F;
+
+ /* If we're using the SGE Doorbell Queue Timer facility, we
+ * don't need to ask the Firmware to send us Egress Queue CIDX
+ * Updates: the Hardware will do this automatically. And
+ * since we send the Ingress Queue CIDX Updates to the
+ * corresponding Ethernet Response Queue, we'll get them very
+ * quickly.
+ */
+ if (!txq->dbqt)
+ wr_mid |= FW_WR_EQUEQ_F | FW_WR_EQUIQ_F;
}
/* Start filling in our Work Request. Note that we do _not_ handle
}
/**
+ * t4_tx_completion_handler - handle CPL_SGE_EGR_UPDATE messages
+ * @rspq: Ethernet RX Response Queue associated with Ethernet TX Queue
+ * @rsp: Response Entry pointer into Response Queue
+ * @gl: Gather List pointer
+ *
+ * For adapters which support the SGE Doorbell Queue Timer facility,
+ * we configure the Ethernet TX Queues to send CIDX Updates to the
+ * Associated Ethernet RX Response Queue with CPL_SGE_EGR_UPDATE
+ * messages. This adds a small load to PCIe Link RX bandwidth and,
+ * potentially, higher CPU Interrupt load, but allows us to respond
+ * much more quickly to the CIDX Updates. This is important for
+ * Upper Layer Software which isn't willing to have a large amount
+ * of TX Data outstanding before receiving DMA Completions.
+ */
+static void t4_tx_completion_handler(struct sge_rspq *rspq,
+ const __be64 *rsp,
+ const struct pkt_gl *gl)
+{
+ u8 opcode = ((const struct rss_header *)rsp)->opcode;
+ struct port_info *pi = netdev_priv(rspq->netdev);
+ struct adapter *adapter = rspq->adap;
+ struct sge *s = &adapter->sge;
+ struct sge_eth_txq *txq;
+
+ /* skip RSS header */
+ rsp++;
+
+ /* FW can send EGR_UPDATEs encapsulated in a CPL_FW4_MSG.
+ */
+ if (unlikely(opcode == CPL_FW4_MSG &&
+ ((const struct cpl_fw4_msg *)rsp)->type ==
+ FW_TYPE_RSSCPL)) {
+ rsp++;
+ opcode = ((const struct rss_header *)rsp)->opcode;
+ rsp++;
+ }
+
+ if (unlikely(opcode != CPL_SGE_EGR_UPDATE)) {
+ pr_info("%s: unexpected FW4/CPL %#x on Rx queue\n",
+ __func__, opcode);
+ return;
+ }
+
+ txq = &s->ethtxq[pi->first_qset + rspq->idx];
+
+ /* We've got the Hardware Consumer Index Update in the Egress Update
+ * message. If we're using the SGE Doorbell Queue Timer mechanism,
+ * these Egress Update messages will be our sole CIDX Updates we get
+ * since we don't want to chew up PCIe bandwidth for both Ingress
+ * Messages and Status Page writes. However, The code which manages
+ * reclaiming successfully DMA'ed TX Work Requests uses the CIDX value
+ * stored in the Status Page at the end of the TX Queue. It's easiest
+ * to simply copy the CIDX Update value from the Egress Update message
+ * to the Status Page. Also note that no Endian issues need to be
+ * considered here since both are Big Endian and we're just copying
+ * bytes consistently ...
+ */
+ if (txq->dbqt) {
+ struct cpl_sge_egr_update *egr;
+
+ egr = (struct cpl_sge_egr_update *)rsp;
+ WRITE_ONCE(txq->q.stat->cidx, egr->cidx);
+ }
+
+ t4_sge_eth_txq_egress_update(adapter, txq, -1);
+}
+
+/**
* t4_ethrx_handler - process an ingress ethernet packet
* @q: the response queue that received the packet
* @rsp: the response queue descriptor holding the RX_PKT message
struct port_info *pi;
int ret = 0;
+ /* If we're looking at TX Queue CIDX Update, handle that separately
+ * and return.
+ */
+ if (unlikely((*(u8 *)rsp == CPL_FW4_MSG) ||
+ (*(u8 *)rsp == CPL_SGE_EGR_UPDATE))) {
+ t4_tx_completion_handler(q, rsp, si);
+ return 0;
+ }
+
if (unlikely(*(u8 *)rsp == cpl_trace_pkt))
return handle_trace_pkt(q->adap, si);
static void sge_tx_timer_cb(struct timer_list *t)
{
- unsigned long m;
- unsigned int i, budget;
struct adapter *adap = from_timer(adap, t, sge.tx_timer);
struct sge *s = &adap->sge;
+ unsigned long m, period;
+ unsigned int i, budget;
for (i = 0; i < BITS_TO_LONGS(s->egr_sz); i++)
for (m = s->txq_maperr[i]; m; m &= m - 1) {
budget = MAX_TIMER_TX_RECLAIM;
i = s->ethtxq_rover;
do {
- struct sge_eth_txq *q = &s->ethtxq[i];
-
- if (q->q.in_use &&
- time_after_eq(jiffies, q->txq->trans_start + HZ / 100) &&
- __netif_tx_trylock(q->txq)) {
- int avail = reclaimable(&q->q);
-
- if (avail) {
- if (avail > budget)
- avail = budget;
-
- free_tx_desc(adap, &q->q, avail, true);
- q->q.in_use -= avail;
- budget -= avail;
- }
- __netif_tx_unlock(q->txq);
- }
+ budget -= t4_sge_eth_txq_egress_update(adap, &s->ethtxq[i],
+ budget);
+ if (!budget)
+ break;
if (++i >= s->ethqsets)
i = 0;
- } while (budget && i != s->ethtxq_rover);
+ } while (i != s->ethtxq_rover);
s->ethtxq_rover = i;
- mod_timer(&s->tx_timer, jiffies + (budget ? TX_QCHECK_PERIOD : 2));
+
+ if (budget == 0) {
+ /* If we found too many reclaimable packets schedule a timer
+ * in the near future to continue where we left off.
+ */
+ period = 2;
+ } else {
+ /* We reclaimed all reclaimable TX Descriptors, so reschedule
+ * at the normal period.
+ */
+ period = TX_QCHECK_PERIOD;
+ }
+
+ mod_timer(&s->tx_timer, jiffies + period);
}
/**
: FW_IQ_IQTYPE_OFLD));
if (fl) {
- enum chip_type chip = CHELSIO_CHIP_VERSION(adap->params.chip);
+ unsigned int chip_ver =
+ CHELSIO_CHIP_VERSION(adap->params.chip);
/* Allocate the ring for the hardware free list (with space
* for its status page) along with the associated software
* the smaller 64-byte value there).
*/
c.fl0dcaen_to_fl0cidxfthresh =
- htons(FW_IQ_CMD_FL0FBMIN_V(chip <= CHELSIO_T5 ?
+ htons(FW_IQ_CMD_FL0FBMIN_V(chip_ver <= CHELSIO_T5 ?
FETCHBURSTMIN_128B_X :
- FETCHBURSTMIN_64B_X) |
- FW_IQ_CMD_FL0FBMAX_V((chip <= CHELSIO_T5) ?
+ FETCHBURSTMIN_64B_T6_X) |
+ FW_IQ_CMD_FL0FBMAX_V((chip_ver <= CHELSIO_T5) ?
FETCHBURSTMAX_512B_X :
FETCHBURSTMAX_256B_X));
c.fl0size = htons(flsz);
adap->sge.egr_map[id - adap->sge.egr_start] = q;
}
+/**
+ * t4_sge_alloc_eth_txq - allocate an Ethernet TX Queue
+ * @adap: the adapter
+ * @txq: the SGE Ethernet TX Queue to initialize
+ * @dev: the Linux Network Device
+ * @netdevq: the corresponding Linux TX Queue
+ * @iqid: the Ingress Queue to which to deliver CIDX Update messages
+ * @dbqt: whether this TX Queue will use the SGE Doorbell Queue Timers
+ */
int t4_sge_alloc_eth_txq(struct adapter *adap, struct sge_eth_txq *txq,
struct net_device *dev, struct netdev_queue *netdevq,
- unsigned int iqid)
+ unsigned int iqid, u8 dbqt)
{
- int ret, nentries;
- struct fw_eq_eth_cmd c;
- struct sge *s = &adap->sge;
+ unsigned int chip_ver = CHELSIO_CHIP_VERSION(adap->params.chip);
struct port_info *pi = netdev_priv(dev);
+ struct sge *s = &adap->sge;
+ struct fw_eq_eth_cmd c;
+ int ret, nentries;
/* Add status entries */
nentries = txq->q.size + s->stat_len / sizeof(struct tx_desc);
FW_EQ_ETH_CMD_VFN_V(0));
c.alloc_to_len16 = htonl(FW_EQ_ETH_CMD_ALLOC_F |
FW_EQ_ETH_CMD_EQSTART_F | FW_LEN16(c));
- c.viid_pkd = htonl(FW_EQ_ETH_CMD_AUTOEQUEQE_F |
- FW_EQ_ETH_CMD_VIID_V(pi->viid));
+
+ /* For TX Ethernet Queues using the SGE Doorbell Queue Timer
+ * mechanism, we use Ingress Queue messages for Hardware Consumer
+ * Index Updates on the TX Queue. Otherwise we have the Hardware
+ * write the CIDX Updates into the Status Page at the end of the
+ * TX Queue.
+ */
+ c.autoequiqe_to_viid = htonl((dbqt
+ ? FW_EQ_ETH_CMD_AUTOEQUIQE_F
+ : FW_EQ_ETH_CMD_AUTOEQUEQE_F) |
+ FW_EQ_ETH_CMD_VIID_V(pi->viid));
+
c.fetchszm_to_iqid =
- htonl(FW_EQ_ETH_CMD_HOSTFCMODE_V(HOSTFCMODE_STATUS_PAGE_X) |
+ htonl(FW_EQ_ETH_CMD_HOSTFCMODE_V(dbqt
+ ? HOSTFCMODE_INGRESS_QUEUE_X
+ : HOSTFCMODE_STATUS_PAGE_X) |
FW_EQ_ETH_CMD_PCIECHN_V(pi->tx_chan) |
FW_EQ_ETH_CMD_FETCHRO_F | FW_EQ_ETH_CMD_IQID_V(iqid));
+
+ /* Note that the CIDX Flush Threshold should match MAX_TX_RECLAIM. */
c.dcaen_to_eqsize =
- htonl(FW_EQ_ETH_CMD_FBMIN_V(FETCHBURSTMIN_64B_X) |
+ htonl(FW_EQ_ETH_CMD_FBMIN_V(chip_ver <= CHELSIO_T5
+ ? FETCHBURSTMIN_64B_X
+ : FETCHBURSTMIN_64B_T6_X) |
FW_EQ_ETH_CMD_FBMAX_V(FETCHBURSTMAX_512B_X) |
FW_EQ_ETH_CMD_CIDXFTHRESH_V(CIDXFLUSHTHRESH_32_X) |
FW_EQ_ETH_CMD_EQSIZE_V(nentries));
+
c.eqaddr = cpu_to_be64(txq->q.phys_addr);
+ /* If we're using the SGE Doorbell Queue Timer mechanism, pass in the
+ * currently configured Timer Index. THis can be changed later via an
+ * ethtool -C tx-usecs {Timer Val} command. Note that the SGE
+ * Doorbell Queue mode is currently automatically enabled in the
+ * Firmware by setting either AUTOEQUEQE or AUTOEQUIQE ...
+ */
+ if (dbqt)
+ c.timeren_timerix =
+ cpu_to_be32(FW_EQ_ETH_CMD_TIMEREN_F |
+ FW_EQ_ETH_CMD_TIMERIX_V(txq->dbqtimerix));
+
ret = t4_wr_mbox(adap, adap->mbox, &c, sizeof(c), &c);
if (ret) {
kfree(txq->q.sdesc);
txq->txq = netdevq;
txq->tso = txq->tx_cso = txq->vlan_ins = 0;
txq->mapping_err = 0;
+ txq->dbqt = dbqt;
+
return 0;
}
struct net_device *dev, unsigned int iqid,
unsigned int cmplqid)
{
- int ret, nentries;
- struct fw_eq_ctrl_cmd c;
- struct sge *s = &adap->sge;
+ unsigned int chip_ver = CHELSIO_CHIP_VERSION(adap->params.chip);
struct port_info *pi = netdev_priv(dev);
+ struct sge *s = &adap->sge;
+ struct fw_eq_ctrl_cmd c;
+ int ret, nentries;
/* Add status entries */
nentries = txq->q.size + s->stat_len / sizeof(struct tx_desc);
FW_EQ_CTRL_CMD_PCIECHN_V(pi->tx_chan) |
FW_EQ_CTRL_CMD_FETCHRO_F | FW_EQ_CTRL_CMD_IQID_V(iqid));
c.dcaen_to_eqsize =
- htonl(FW_EQ_CTRL_CMD_FBMIN_V(FETCHBURSTMIN_64B_X) |
+ htonl(FW_EQ_CTRL_CMD_FBMIN_V(chip_ver <= CHELSIO_T5
+ ? FETCHBURSTMIN_64B_X
+ : FETCHBURSTMIN_64B_T6_X) |
FW_EQ_CTRL_CMD_FBMAX_V(FETCHBURSTMAX_512B_X) |
FW_EQ_CTRL_CMD_CIDXFTHRESH_V(CIDXFLUSHTHRESH_32_X) |
FW_EQ_CTRL_CMD_EQSIZE_V(nentries));
struct net_device *dev, unsigned int iqid,
unsigned int uld_type)
{
+ unsigned int chip_ver = CHELSIO_CHIP_VERSION(adap->params.chip);
int ret, nentries;
struct fw_eq_ofld_cmd c;
struct sge *s = &adap->sge;
FW_EQ_OFLD_CMD_PCIECHN_V(pi->tx_chan) |
FW_EQ_OFLD_CMD_FETCHRO_F | FW_EQ_OFLD_CMD_IQID_V(iqid));
c.dcaen_to_eqsize =
- htonl(FW_EQ_OFLD_CMD_FBMIN_V(FETCHBURSTMIN_64B_X) |
+ htonl(FW_EQ_OFLD_CMD_FBMIN_V(chip_ver <= CHELSIO_T5
+ ? FETCHBURSTMIN_64B_X
+ : FETCHBURSTMIN_64B_T6_X) |
FW_EQ_OFLD_CMD_FBMAX_V(FETCHBURSTMAX_512B_X) |
FW_EQ_OFLD_CMD_CIDXFTHRESH_V(CIDXFLUSHTHRESH_32_X) |
FW_EQ_OFLD_CMD_EQSIZE_V(nentries));
OSDN Git Service
