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Diffstat (limited to 'sys/dev/netmap/ixgbe_netmap.h')
-rw-r--r--sys/dev/netmap/ixgbe_netmap.h74
1 files changed, 27 insertions, 47 deletions
diff --git a/sys/dev/netmap/ixgbe_netmap.h b/sys/dev/netmap/ixgbe_netmap.h
index 4dea6639d325..a617cc4c2429 100644
--- a/sys/dev/netmap/ixgbe_netmap.h
+++ b/sys/dev/netmap/ixgbe_netmap.h
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2011 Matteo Landi, Luigi Rizzo. All rights reserved.
+ * Copyright (C) 2011-2014 Matteo Landi, Luigi Rizzo. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
@@ -141,14 +141,13 @@ ixgbe_netmap_reg(struct netmap_adapter *na, int onoff)
/*
* Reconcile kernel and user view of the transmit ring.
*
- * Userspace wants to send packets up to the one before ring->cur,
+ * All information is in the kring.
+ * Userspace wants to send packets up to the one before kring->rhead,
* kernel knows kring->nr_hwcur is the first unsent packet.
*
* Here we push packets out (as many as possible), and possibly
* reclaim buffers from previously completed transmission.
*
- * ring->avail is not used on input, but it is updated on return.
- *
* The caller (netmap) guarantees that there is only one instance
* running at any time. Any interference with other driver
* methods should be handled by the individual drivers.
@@ -161,9 +160,9 @@ ixgbe_netmap_txsync(struct netmap_adapter *na, u_int ring_nr, int flags)
struct netmap_ring *ring = kring->ring;
u_int nm_i; /* index into the netmap ring */
u_int nic_i; /* index into the NIC ring */
- u_int n, new_slots;
+ u_int n;
u_int const lim = kring->nkr_num_slots - 1;
- u_int const cur = nm_txsync_prologue(kring, &new_slots);
+ u_int const head = kring->rhead;
/*
* interrupts on every tx packet are expensive so request
* them every half ring, or where NS_REPORT is set
@@ -175,9 +174,6 @@ ixgbe_netmap_txsync(struct netmap_adapter *na, u_int ring_nr, int flags)
struct tx_ring *txr = &adapter->tx_rings[ring_nr];
int reclaim_tx;
- if (cur > lim) /* error checking in nm_txsync_prologue() */
- return netmap_ring_reinit(kring);
-
bus_dmamap_sync(txr->txdma.dma_tag, txr->txdma.dma_map,
BUS_DMASYNC_POSTREAD);
@@ -199,7 +195,7 @@ ixgbe_netmap_txsync(struct netmap_adapter *na, u_int ring_nr, int flags)
*/
/*
- * If we have packets to send (kring->nr_hwcur != ring->cur)
+ * If we have packets to send (kring->nr_hwcur != kring->rhead)
* iterate over the netmap ring, fetch length and update
* the corresponding slot in the NIC ring. Some drivers also
* need to update the buffer's physical address in the NIC slot
@@ -217,13 +213,13 @@ ixgbe_netmap_txsync(struct netmap_adapter *na, u_int ring_nr, int flags)
*/
nm_i = kring->nr_hwcur;
- if (nm_i != cur) { /* we have new packets to send */
+ if (nm_i != head) { /* we have new packets to send */
nic_i = netmap_idx_k2n(kring, nm_i);
__builtin_prefetch(&ring->slot[nm_i]);
__builtin_prefetch(&txr->tx_buffers[nic_i]);
- for (n = 0; nm_i != cur; n++) {
+ for (n = 0; nm_i != head; n++) {
struct netmap_slot *slot = &ring->slot[nm_i];
u_int len = slot->len;
uint64_t paddr;
@@ -262,9 +258,7 @@ ixgbe_netmap_txsync(struct netmap_adapter *na, u_int ring_nr, int flags)
nm_i = nm_next(nm_i, lim);
nic_i = nm_next(nic_i, lim);
}
- kring->nr_hwcur = cur; /* the saved ring->cur */
- /* decrease avail by # of packets sent minus previous ones */
- kring->nr_hwavail -= new_slots;
+ kring->nr_hwcur = head;
/* synchronize the NIC ring */
bus_dmamap_sync(txr->txdma.dma_tag, txr->txdma.dma_map,
@@ -281,7 +275,7 @@ ixgbe_netmap_txsync(struct netmap_adapter *na, u_int ring_nr, int flags)
*/
if (flags & NAF_FORCE_RECLAIM) {
reclaim_tx = 1; /* forced reclaim */
- } else if (kring->nr_hwavail > 0) {
+ } else if (!nm_kr_txempty(kring)) {
reclaim_tx = 0; /* have buffers, no reclaim */
} else {
/*
@@ -321,21 +315,13 @@ ixgbe_netmap_txsync(struct netmap_adapter *na, u_int ring_nr, int flags)
nic_i -= kring->nkr_num_slots;
}
if (nic_i != txr->next_to_clean) {
- n = (nic_i + lim + 1) - txr->next_to_clean;
- if (n > lim)
- n -= lim + 1;
/* some tx completed, increment avail */
txr->next_to_clean = nic_i;
- kring->nr_hwavail += n;
- if (kring->nr_hwavail > lim) {
- RD(5, "bad hwavail %d",
- kring->nr_hwavail);
- return netmap_ring_reinit(kring);
- }
+ kring->nr_hwtail = nm_prev(netmap_idx_n2k(kring, nic_i), lim);
}
}
- nm_txsync_finalize(kring, cur);
+ nm_txsync_finalize(kring);
return 0;
}
@@ -347,14 +333,9 @@ ixgbe_netmap_txsync(struct netmap_adapter *na, u_int ring_nr, int flags)
* The caller guarantees a single invocations, but races against
* the rest of the driver should be handled here.
*
- * When called, userspace has released buffers up to
- * ring->cur - ring->reserved (last one excluded).
- *
- * The last interrupt reported kring->nr_hwavail slots available
- * after kring->nr_hwcur.
- * We must subtract the newly consumed slots (cur - nr_hwcur)
- * from nr_hwavail, make the descriptors available for the next reads,
- * and set kring->nr_hwcur = ring->cur and ring->avail = kring->nr_hwavail.
+ * On call, kring->rhead is the first packet that userspace wants
+ * to keep, and kring->rcur is the wakeup point.
+ * The kernel has previously reported packets up to kring->rtail.
*
* If (flags & NAF_FORCE_READ) also check for incoming packets irrespective
* of whether or not we received an interrupt.
@@ -367,16 +348,16 @@ ixgbe_netmap_rxsync(struct netmap_adapter *na, u_int ring_nr, int flags)
struct netmap_ring *ring = kring->ring;
u_int nm_i; /* index into the netmap ring */
u_int nic_i; /* index into the NIC ring */
- u_int n, resvd;
+ u_int n;
u_int const lim = kring->nkr_num_slots - 1;
- u_int const cur = nm_rxsync_prologue(kring, &resvd); /* cur + res */
+ u_int const head = nm_rxsync_prologue(kring);
int force_update = (flags & NAF_FORCE_READ) || kring->nr_kflags & NKR_PENDINTR;
/* device-specific */
struct adapter *adapter = ifp->if_softc;
struct rx_ring *rxr = &adapter->rx_rings[ring_nr];
- if (cur > lim)
+ if (head > lim)
return netmap_ring_reinit(kring);
/* XXX check sync modes */
@@ -391,8 +372,8 @@ ixgbe_netmap_rxsync(struct netmap_adapter *na, u_int ring_nr, int flags)
* and they may differ in case if_init() has been called while
* in netmap mode. For the receive ring we have
*
- * nm_i = (kring->nr_hwcur + kring->nr_hwavail) % ring_size
* nic_i = rxr->next_to_check;
+ * nm_i = kring->nr_hwtail (previous)
* and
* nm_i == (nic_i + kring->nkr_hwofs) % ring_size
*
@@ -402,7 +383,7 @@ ixgbe_netmap_rxsync(struct netmap_adapter *na, u_int ring_nr, int flags)
int crclen = ix_crcstrip ? 0 : 4;
uint16_t slot_flags = kring->nkr_slot_flags;
- nic_i = rxr->next_to_check;
+ nic_i = rxr->next_to_check; // or also k2n(kring->nr_hwtail)
nm_i = netmap_idx_n2k(kring, nic_i);
for (n = 0; ; n++) {
@@ -425,23 +406,23 @@ ixgbe_netmap_rxsync(struct netmap_adapter *na, u_int ring_nr, int flags)
ix_rx_miss_bufs += n;
}
rxr->next_to_check = nic_i;
- kring->nr_hwavail += n;
+ kring->nr_hwtail = nm_i;
}
kring->nr_kflags &= ~NKR_PENDINTR;
}
/*
* Second part: skip past packets that userspace has released.
- * (kring->nr_hwcur to ring->cur - ring->reserved excluded),
+ * (kring->nr_hwcur to kring->rhead excluded),
* and make the buffers available for reception.
* As usual nm_i is the index in the netmap ring,
* nic_i is the index in the NIC ring, and
* nm_i == (nic_i + kring->nkr_hwofs) % ring_size
*/
nm_i = kring->nr_hwcur;
- if (nm_i != cur) {
+ if (nm_i != head) {
nic_i = netmap_idx_k2n(kring, nm_i);
- for (n = 0; nm_i != cur; n++) {
+ for (n = 0; nm_i != head; n++) {
struct netmap_slot *slot = &ring->slot[nm_i];
uint64_t paddr;
void *addr = PNMB(slot, &paddr);
@@ -464,8 +445,7 @@ ixgbe_netmap_rxsync(struct netmap_adapter *na, u_int ring_nr, int flags)
nm_i = nm_next(nm_i, lim);
nic_i = nm_next(nic_i, lim);
}
- kring->nr_hwavail -= n;
- kring->nr_hwcur = cur;
+ kring->nr_hwcur = head;
bus_dmamap_sync(rxr->rxdma.dma_tag, rxr->rxdma.dma_map,
BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
@@ -473,12 +453,12 @@ ixgbe_netmap_rxsync(struct netmap_adapter *na, u_int ring_nr, int flags)
* IMPORTANT: we must leave one free slot in the ring,
* so move nic_i back by one unit
*/
- nic_i = (nic_i == 0) ? lim : nic_i - 1;
+ nic_i = nm_prev(nic_i, lim);
IXGBE_WRITE_REG(&adapter->hw, IXGBE_RDT(rxr->me), nic_i);
}
/* tell userspace that there might be new packets */
- ring->avail = kring->nr_hwavail - resvd;
+ nm_rxsync_finalize(kring);
return 0;