diff options
author | David S. Miller <davem@davemloft.net> | 2023-09-20 12:52:31 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2023-09-20 12:52:31 +0300 |
commit | 3a69ab875233734bc434402379100272cd70bde2 (patch) | |
tree | fb42e37d053dc6e2e247f735f02d8449037d7ea2 | |
parent | 4fa7011d4f22d5b2e14cba19b524a4f90268b5c1 (diff) | |
parent | 529cdfd5e3a69bdc095ce3d535cadf897b787610 (diff) | |
download | linux-3a69ab875233734bc434402379100272cd70bde2.tar.xz |
Merge branch 'ionic-better-tx-sg=handling'
Shannon Nelson says:
====================
ionic: better Tx SG handling
The primary patch here is to be sure we're not hitting linearize on a Tx
skb when we don't really need to. The other two are related details.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | drivers/net/ethernet/pensando/ionic/ionic_dev.h | 3 | ||||
-rw-r--r-- | drivers/net/ethernet/pensando/ionic/ionic_lif.c | 12 | ||||
-rw-r--r-- | drivers/net/ethernet/pensando/ionic/ionic_txrx.c | 77 |
3 files changed, 82 insertions, 10 deletions
diff --git a/drivers/net/ethernet/pensando/ionic/ionic_dev.h b/drivers/net/ethernet/pensando/ionic/ionic_dev.h index 6aac98bcb9f4..b51febf86504 100644 --- a/drivers/net/ethernet/pensando/ionic/ionic_dev.h +++ b/drivers/net/ethernet/pensando/ionic/ionic_dev.h @@ -7,6 +7,7 @@ #include <linux/atomic.h> #include <linux/mutex.h> #include <linux/workqueue.h> +#include <linux/skbuff.h> #include "ionic_if.h" #include "ionic_regs.h" @@ -216,7 +217,7 @@ struct ionic_desc_info { }; unsigned int bytes; unsigned int nbufs; - struct ionic_buf_info bufs[IONIC_MAX_FRAGS]; + struct ionic_buf_info bufs[MAX_SKB_FRAGS + 1]; ionic_desc_cb cb; void *cb_arg; }; diff --git a/drivers/net/ethernet/pensando/ionic/ionic_lif.c b/drivers/net/ethernet/pensando/ionic/ionic_lif.c index 2c3e36b2dd7f..edc14730ce88 100644 --- a/drivers/net/ethernet/pensando/ionic/ionic_lif.c +++ b/drivers/net/ethernet/pensando/ionic/ionic_lif.c @@ -3831,6 +3831,18 @@ static void ionic_lif_queue_identify(struct ionic_lif *lif) qtype, qti->max_sg_elems); dev_dbg(ionic->dev, " qtype[%d].sg_desc_stride = %d\n", qtype, qti->sg_desc_stride); + + if (qti->max_sg_elems >= IONIC_MAX_FRAGS) { + qti->max_sg_elems = IONIC_MAX_FRAGS - 1; + dev_dbg(ionic->dev, "limiting qtype %d max_sg_elems to IONIC_MAX_FRAGS-1 %d\n", + qtype, qti->max_sg_elems); + } + + if (qti->max_sg_elems > MAX_SKB_FRAGS) { + qti->max_sg_elems = MAX_SKB_FRAGS; + dev_dbg(ionic->dev, "limiting qtype %d max_sg_elems to MAX_SKB_FRAGS %d\n", + qtype, qti->max_sg_elems); + } } } diff --git a/drivers/net/ethernet/pensando/ionic/ionic_txrx.c b/drivers/net/ethernet/pensando/ionic/ionic_txrx.c index 26798fc635db..c08a61323066 100644 --- a/drivers/net/ethernet/pensando/ionic/ionic_txrx.c +++ b/drivers/net/ethernet/pensando/ionic/ionic_txrx.c @@ -1239,25 +1239,84 @@ static int ionic_tx(struct ionic_queue *q, struct sk_buff *skb) static int ionic_tx_descs_needed(struct ionic_queue *q, struct sk_buff *skb) { struct ionic_tx_stats *stats = q_to_tx_stats(q); + bool too_many_frags = false; + skb_frag_t *frag; + int desc_bufs; + int chunk_len; + int frag_rem; + int tso_rem; + int seg_rem; + bool encap; + int hdrlen; int ndescs; int err; /* Each desc is mss long max, so a descriptor for each gso_seg */ - if (skb_is_gso(skb)) + if (skb_is_gso(skb)) { ndescs = skb_shinfo(skb)->gso_segs; - else + } else { ndescs = 1; + if (skb_shinfo(skb)->nr_frags > q->max_sg_elems) { + too_many_frags = true; + goto linearize; + } + } - /* If non-TSO, just need 1 desc and nr_frags sg elems */ - if (skb_shinfo(skb)->nr_frags <= q->max_sg_elems) + /* If non-TSO, or no frags to check, we're done */ + if (!skb_is_gso(skb) || !skb_shinfo(skb)->nr_frags) return ndescs; - /* Too many frags, so linearize */ - err = skb_linearize(skb); - if (err) - return err; + /* We need to scan the skb to be sure that none of the MTU sized + * packets in the TSO will require more sgs per descriptor than we + * can support. We loop through the frags, add up the lengths for + * a packet, and count the number of sgs used per packet. + */ + tso_rem = skb->len; + frag = skb_shinfo(skb)->frags; + encap = skb->encapsulation; + + /* start with just hdr in first part of first descriptor */ + if (encap) + hdrlen = skb_inner_tcp_all_headers(skb); + else + hdrlen = skb_tcp_all_headers(skb); + seg_rem = min_t(int, tso_rem, hdrlen + skb_shinfo(skb)->gso_size); + frag_rem = hdrlen; + + while (tso_rem > 0) { + desc_bufs = 0; + while (seg_rem > 0) { + desc_bufs++; + + /* We add the +1 because we can take buffers for one + * more than we have SGs: one for the initial desc data + * in addition to the SG segments that might follow. + */ + if (desc_bufs > q->max_sg_elems + 1) { + too_many_frags = true; + goto linearize; + } + + if (frag_rem == 0) { + frag_rem = skb_frag_size(frag); + frag++; + } + chunk_len = min(frag_rem, seg_rem); + frag_rem -= chunk_len; + tso_rem -= chunk_len; + seg_rem -= chunk_len; + } + + seg_rem = min_t(int, tso_rem, skb_shinfo(skb)->gso_size); + } - stats->linearize++; +linearize: + if (too_many_frags) { + err = skb_linearize(skb); + if (err) + return err; + stats->linearize++; + } return ndescs; } |