[S390] qeth: preallocated qeth header for hiper socket
For hiper socket devices this patch will economize the reallocation
of the tx skb data segment by allocating separate memory for the qdio
transport information (qeth header).
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c
index 3e1d138..dd72c3c 100644
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -2604,6 +2604,7 @@
int tx_bytes = skb->len;
enum qeth_large_send_types large_send = QETH_LARGE_SEND_NO;
struct qeth_eddp_context *ctx = NULL;
+ int data_offset = -1;
if ((card->info.type == QETH_CARD_TYPE_IQD) &&
(skb->protocol != htons(ETH_P_IPV6)) &&
@@ -2624,14 +2625,28 @@
card->perf_stats.outbound_start_time = qeth_get_micros();
}
- /* create a clone with writeable headroom */
- new_skb = skb_realloc_headroom(skb, sizeof(struct qeth_hdr_tso) +
- VLAN_HLEN);
- if (!new_skb)
- goto tx_drop;
+ if (skb_is_gso(skb))
+ large_send = card->options.large_send;
+
+ if ((card->info.type == QETH_CARD_TYPE_IQD) && (!large_send) &&
+ (skb_shinfo(skb)->nr_frags == 0)) {
+ new_skb = skb;
+ data_offset = ETH_HLEN;
+ hdr = kmem_cache_alloc(qeth_core_header_cache, GFP_ATOMIC);
+ if (!hdr)
+ goto tx_drop;
+ elements_needed++;
+ } else {
+ /* create a clone with writeable headroom */
+ new_skb = skb_realloc_headroom(skb, sizeof(struct qeth_hdr_tso)
+ + VLAN_HLEN);
+ if (!new_skb)
+ goto tx_drop;
+ }
if (card->info.type == QETH_CARD_TYPE_IQD) {
- skb_pull(new_skb, ETH_HLEN);
+ if (data_offset < 0)
+ skb_pull(new_skb, ETH_HLEN);
} else {
if (new_skb->protocol == htons(ETH_P_IP)) {
if (card->dev->type == ARPHRD_IEEE802_TR)
@@ -2657,9 +2672,6 @@
netif_stop_queue(dev);
- if (skb_is_gso(new_skb))
- large_send = card->options.large_send;
-
/* fix hardware limitation: as long as we do not have sbal
* chaining we can not send long frag lists so we temporary
* switch to EDDP
@@ -2677,9 +2689,16 @@
qeth_tso_fill_header(card, hdr, new_skb);
elements_needed++;
} else {
- hdr = (struct qeth_hdr *)skb_push(new_skb,
+ if (data_offset < 0) {
+ hdr = (struct qeth_hdr *)skb_push(new_skb,
sizeof(struct qeth_hdr));
- qeth_l3_fill_header(card, hdr, new_skb, ipv, cast_type);
+ qeth_l3_fill_header(card, hdr, new_skb, ipv,
+ cast_type);
+ } else {
+ qeth_l3_fill_header(card, hdr, new_skb, ipv,
+ cast_type);
+ hdr->hdr.l3.length = new_skb->len - data_offset;
+ }
}
if (large_send == QETH_LARGE_SEND_EDDP) {
@@ -2695,8 +2714,11 @@
} else {
int elems = qeth_get_elements_no(card, (void *)hdr, new_skb,
elements_needed);
- if (!elems)
+ if (!elems) {
+ if (data_offset >= 0)
+ kmem_cache_free(qeth_core_header_cache, hdr);
goto tx_drop;
+ }
elements_needed += elems;
}
@@ -2709,7 +2731,7 @@
elements_needed, ctx);
else
rc = qeth_do_send_packet_fast(card, queue, new_skb, hdr,
- elements_needed, ctx);
+ elements_needed, ctx, data_offset, 0);
if (!rc) {
card->stats.tx_packets++;
@@ -2737,6 +2759,9 @@
if (ctx != NULL)
qeth_eddp_put_context(ctx);
+ if (data_offset >= 0)
+ kmem_cache_free(qeth_core_header_cache, hdr);
+
if (rc == -EBUSY) {
if (new_skb != skb)
dev_kfree_skb_any(new_skb);