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authorHerbert Xu <herbert@gondor.apana.org.au>2009-04-16 02:02:07 -0700
committerDavid S. Miller <davem@davemloft.net>2009-04-16 02:02:07 -0700
commit76620aafd66f0004829764940c5466144969cffc (patch)
tree38041e6938121b5611546c582cd23f289db047b0
parent861ab44059350e5cab350238606cf8814abab93b (diff)
gro: New frags interface to avoid copying shinfo
It turns out that copying a 16-byte area at ~800k times a second can be really expensive :) This patch redesigns the frags GRO interface to avoid copying that area twice. The two disciples of the frags interface have been converted. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--drivers/net/cxgb3/adapter.h2
-rw-r--r--drivers/net/cxgb3/sge.c53
-rw-r--r--drivers/net/sfc/rx.c26
-rw-r--r--include/linux/if_vlan.h6
-rw-r--r--include/linux/netdevice.h22
-rw-r--r--net/8021q/vlan_core.c4
-rw-r--r--net/core/dev.c81
7 files changed, 101 insertions, 93 deletions
diff --git a/drivers/net/cxgb3/adapter.h b/drivers/net/cxgb3/adapter.h
index 714df2b675e..322434ac42f 100644
--- a/drivers/net/cxgb3/adapter.h
+++ b/drivers/net/cxgb3/adapter.h
@@ -195,7 +195,7 @@ struct sge_qset { /* an SGE queue set */
struct sge_rspq rspq;
struct sge_fl fl[SGE_RXQ_PER_SET];
struct sge_txq txq[SGE_TXQ_PER_SET];
- struct napi_gro_fraginfo lro_frag_tbl;
+ int nomem;
int lro_enabled;
void *lro_va;
struct net_device *netdev;
diff --git a/drivers/net/cxgb3/sge.c b/drivers/net/cxgb3/sge.c
index 26d3587f339..73d569e758e 100644
--- a/drivers/net/cxgb3/sge.c
+++ b/drivers/net/cxgb3/sge.c
@@ -654,7 +654,8 @@ static void t3_reset_qset(struct sge_qset *q)
q->txq_stopped = 0;
q->tx_reclaim_timer.function = NULL; /* for t3_stop_sge_timers() */
q->rx_reclaim_timer.function = NULL;
- q->lro_frag_tbl.nr_frags = q->lro_frag_tbl.len = 0;
+ q->nomem = 0;
+ napi_free_frags(&q->napi);
}
@@ -2074,20 +2075,19 @@ static void lro_add_page(struct adapter *adap, struct sge_qset *qs,
struct sge_fl *fl, int len, int complete)
{
struct rx_sw_desc *sd = &fl->sdesc[fl->cidx];
+ struct sk_buff *skb = NULL;
struct cpl_rx_pkt *cpl;
- struct skb_frag_struct *rx_frag = qs->lro_frag_tbl.frags;
- int nr_frags = qs->lro_frag_tbl.nr_frags;
- int frag_len = qs->lro_frag_tbl.len;
+ struct skb_frag_struct *rx_frag;
+ int nr_frags;
int offset = 0;
- if (!nr_frags) {
- offset = 2 + sizeof(struct cpl_rx_pkt);
- qs->lro_va = cpl = sd->pg_chunk.va + 2;
+ if (!qs->nomem) {
+ skb = napi_get_frags(&qs->napi);
+ qs->nomem = !skb;
}
fl->credits--;
- len -= offset;
pci_dma_sync_single_for_cpu(adap->pdev,
pci_unmap_addr(sd, dma_addr),
fl->buf_size - SGE_PG_RSVD,
@@ -2100,21 +2100,38 @@ static void lro_add_page(struct adapter *adap, struct sge_qset *qs,
fl->alloc_size,
PCI_DMA_FROMDEVICE);
+ if (!skb) {
+ put_page(sd->pg_chunk.page);
+ if (complete)
+ qs->nomem = 0;
+ return;
+ }
+
+ rx_frag = skb_shinfo(skb)->frags;
+ nr_frags = skb_shinfo(skb)->nr_frags;
+
+ if (!nr_frags) {
+ offset = 2 + sizeof(struct cpl_rx_pkt);
+ qs->lro_va = sd->pg_chunk.va + 2;
+ }
+ len -= offset;
+
prefetch(qs->lro_va);
rx_frag += nr_frags;
rx_frag->page = sd->pg_chunk.page;
rx_frag->page_offset = sd->pg_chunk.offset + offset;
rx_frag->size = len;
- frag_len += len;
- qs->lro_frag_tbl.nr_frags++;
- qs->lro_frag_tbl.len = frag_len;
+ skb->len += len;
+ skb->data_len += len;
+ skb->truesize += len;
+ skb_shinfo(skb)->nr_frags++;
if (!complete)
return;
- qs->lro_frag_tbl.ip_summed = CHECKSUM_UNNECESSARY;
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
cpl = qs->lro_va;
if (unlikely(cpl->vlan_valid)) {
@@ -2123,15 +2140,11 @@ static void lro_add_page(struct adapter *adap, struct sge_qset *qs,
struct vlan_group *grp = pi->vlan_grp;
if (likely(grp != NULL)) {
- vlan_gro_frags(&qs->napi, grp, ntohs(cpl->vlan),
- &qs->lro_frag_tbl);
- goto out;
+ vlan_gro_frags(&qs->napi, grp, ntohs(cpl->vlan));
+ return;
}
}
- napi_gro_frags(&qs->napi, &qs->lro_frag_tbl);
-
-out:
- qs->lro_frag_tbl.nr_frags = qs->lro_frag_tbl.len = 0;
+ napi_gro_frags(&qs->napi);
}
/**
@@ -2300,8 +2313,6 @@ no_mem:
if (fl->use_pages) {
void *addr = fl->sdesc[fl->cidx].pg_chunk.va;
- prefetch(&qs->lro_frag_tbl);
-
prefetch(addr);
#if L1_CACHE_BYTES < 128
prefetch(addr + L1_CACHE_BYTES);
diff --git a/drivers/net/sfc/rx.c b/drivers/net/sfc/rx.c
index 66d7fe3db3e..01f9432c31e 100644
--- a/drivers/net/sfc/rx.c
+++ b/drivers/net/sfc/rx.c
@@ -450,17 +450,27 @@ static void efx_rx_packet_lro(struct efx_channel *channel,
/* Pass the skb/page into the LRO engine */
if (rx_buf->page) {
- struct napi_gro_fraginfo info;
+ struct sk_buff *skb = napi_get_frags(napi);
- info.frags[0].page = rx_buf->page;
- info.frags[0].page_offset = efx_rx_buf_offset(rx_buf);
- info.frags[0].size = rx_buf->len;
- info.nr_frags = 1;
- info.ip_summed = CHECKSUM_UNNECESSARY;
- info.len = rx_buf->len;
+ if (!skb) {
+ put_page(rx_buf->page);
+ goto out;
+ }
+
+ skb_shinfo(skb)->frags[0].page = rx_buf->page;
+ skb_shinfo(skb)->frags[0].page_offset =
+ efx_rx_buf_offset(rx_buf);
+ skb_shinfo(skb)->frags[0].size = rx_buf->len;
+ skb_shinfo(skb)->nr_frags = 1;
+
+ skb->len = rx_buf->len;
+ skb->data_len = rx_buf->len;
+ skb->truesize += rx_buf->len;
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
- napi_gro_frags(napi, &info);
+ napi_gro_frags(napi);
+out:
EFX_BUG_ON_PARANOID(rx_buf->skb);
rx_buf->page = NULL;
} else {
diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h
index e1ff5b14310..7ff9af1d0f0 100644
--- a/include/linux/if_vlan.h
+++ b/include/linux/if_vlan.h
@@ -118,8 +118,7 @@ extern int vlan_hwaccel_do_receive(struct sk_buff *skb);
extern int vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp,
unsigned int vlan_tci, struct sk_buff *skb);
extern int vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp,
- unsigned int vlan_tci,
- struct napi_gro_fraginfo *info);
+ unsigned int vlan_tci);
#else
static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev)
@@ -154,8 +153,7 @@ static inline int vlan_gro_receive(struct napi_struct *napi,
}
static inline int vlan_gro_frags(struct napi_struct *napi,
- struct vlan_group *grp, unsigned int vlan_tci,
- struct napi_gro_fraginfo *info)
+ struct vlan_group *grp, unsigned int vlan_tci)
{
return NET_RX_DROP;
}
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 2e7783f4a75..54db3ebf219 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1047,14 +1047,6 @@ struct packet_type {
struct list_head list;
};
-struct napi_gro_fraginfo {
- skb_frag_t frags[MAX_SKB_FRAGS];
- unsigned int nr_frags;
- unsigned int ip_summed;
- unsigned int len;
- __wsum csum;
-};
-
#include <linux/interrupt.h>
#include <linux/notifier.h>
@@ -1442,12 +1434,18 @@ extern int napi_gro_receive(struct napi_struct *napi,
struct sk_buff *skb);
extern void napi_reuse_skb(struct napi_struct *napi,
struct sk_buff *skb);
-extern struct sk_buff * napi_fraginfo_skb(struct napi_struct *napi,
- struct napi_gro_fraginfo *info);
+extern struct sk_buff * napi_get_frags(struct napi_struct *napi);
extern int napi_frags_finish(struct napi_struct *napi,
struct sk_buff *skb, int ret);
-extern int napi_gro_frags(struct napi_struct *napi,
- struct napi_gro_fraginfo *info);
+extern struct sk_buff * napi_frags_skb(struct napi_struct *napi);
+extern int napi_gro_frags(struct napi_struct *napi);
+
+static inline void napi_free_frags(struct napi_struct *napi)
+{
+ kfree_skb(napi->skb);
+ napi->skb = NULL;
+}
+
extern void netif_nit_deliver(struct sk_buff *skb);
extern int dev_valid_name(const char *name);
extern int dev_ioctl(struct net *net, unsigned int cmd, void __user *);
diff --git a/net/8021q/vlan_core.c b/net/8021q/vlan_core.c
index 654e45f5719..c1f51e4a01b 100644
--- a/net/8021q/vlan_core.c
+++ b/net/8021q/vlan_core.c
@@ -114,9 +114,9 @@ int vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp,
EXPORT_SYMBOL(vlan_gro_receive);
int vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp,
- unsigned int vlan_tci, struct napi_gro_fraginfo *info)
+ unsigned int vlan_tci)
{
- struct sk_buff *skb = napi_fraginfo_skb(napi, info);
+ struct sk_buff *skb = napi_frags_skb(napi);
if (!skb)
return NET_RX_DROP;
diff --git a/net/core/dev.c b/net/core/dev.c
index 91d792d17e0..619fa141b8f 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2519,16 +2519,10 @@ void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
}
EXPORT_SYMBOL(napi_reuse_skb);
-struct sk_buff *napi_fraginfo_skb(struct napi_struct *napi,
- struct napi_gro_fraginfo *info)
+struct sk_buff *napi_get_frags(struct napi_struct *napi)
{
struct net_device *dev = napi->dev;
struct sk_buff *skb = napi->skb;
- struct ethhdr *eth;
- skb_frag_t *frag;
- int i;
-
- napi->skb = NULL;
if (!skb) {
skb = netdev_alloc_skb(dev, GRO_MAX_HEAD + NET_IP_ALIGN);
@@ -2536,47 +2530,14 @@ struct sk_buff *napi_fraginfo_skb(struct napi_struct *napi,
goto out;
skb_reserve(skb, NET_IP_ALIGN);
- }
-
- BUG_ON(info->nr_frags > MAX_SKB_FRAGS);
- frag = &info->frags[info->nr_frags - 1];
- for (i = skb_shinfo(skb)->nr_frags; i < info->nr_frags; i++) {
- skb_fill_page_desc(skb, i, frag->page, frag->page_offset,
- frag->size);
- frag++;
+ napi->skb = skb;
}
- skb_shinfo(skb)->nr_frags = info->nr_frags;
-
- skb->data_len = info->len;
- skb->len += info->len;
- skb->truesize += info->len;
-
- skb_reset_mac_header(skb);
- skb_gro_reset_offset(skb);
-
- eth = skb_gro_header(skb, sizeof(*eth));
- if (!eth) {
- napi_reuse_skb(napi, skb);
- skb = NULL;
- goto out;
- }
-
- skb_gro_pull(skb, sizeof(*eth));
-
- /*
- * This works because the only protocols we care about don't require
- * special handling. We'll fix it up properly at the end.
- */
- skb->protocol = eth->h_proto;
-
- skb->ip_summed = info->ip_summed;
- skb->csum = info->csum;
out:
return skb;
}
-EXPORT_SYMBOL(napi_fraginfo_skb);
+EXPORT_SYMBOL(napi_get_frags);
int napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb, int ret)
{
@@ -2606,9 +2567,39 @@ int napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb, int ret)
}
EXPORT_SYMBOL(napi_frags_finish);
-int napi_gro_frags(struct napi_struct *napi, struct napi_gro_fraginfo *info)
+struct sk_buff *napi_frags_skb(struct napi_struct *napi)
+{
+ struct sk_buff *skb = napi->skb;
+ struct ethhdr *eth;
+
+ napi->skb = NULL;
+
+ skb_reset_mac_header(skb);
+ skb_gro_reset_offset(skb);
+
+ eth = skb_gro_header(skb, sizeof(*eth));
+ if (!eth) {
+ napi_reuse_skb(napi, skb);
+ skb = NULL;
+ goto out;
+ }
+
+ skb_gro_pull(skb, sizeof(*eth));
+
+ /*
+ * This works because the only protocols we care about don't require
+ * special handling. We'll fix it up properly at the end.
+ */
+ skb->protocol = eth->h_proto;
+
+out:
+ return skb;
+}
+EXPORT_SYMBOL(napi_frags_skb);
+
+int napi_gro_frags(struct napi_struct *napi)
{
- struct sk_buff *skb = napi_fraginfo_skb(napi, info);
+ struct sk_buff *skb = napi_frags_skb(napi);
if (!skb)
return NET_RX_DROP;
@@ -2712,7 +2703,7 @@ void netif_napi_del(struct napi_struct *napi)
struct sk_buff *skb, *next;
list_del_init(&napi->dev_list);
- kfree_skb(napi->skb);
+ napi_free_frags(napi);
for (skb = napi->gro_list; skb; skb = next) {
next = skb->next;