[PATCH 2/3 2.6.27] cxgb3 - Add page support to jumbo frame Rx queue

From: Divy Le Ray
Date: Tue May 20 2008 - 21:58:30 EST


From: Divy Le Ray <divy@xxxxxxxxxxx>

Add page support to Jumbo frame Rx queues.

Signed-off-by: Divy Le Ray <divy@xxxxxxxxxxx>
---

drivers/net/cxgb3/adapter.h | 4 +
drivers/net/cxgb3/sge.c | 118 ++++++++++++++++++++++++++++++-------------
2 files changed, 86 insertions(+), 36 deletions(-)

diff --git a/drivers/net/cxgb3/adapter.h b/drivers/net/cxgb3/adapter.h
index acebe43..263e4fa 100644
--- a/drivers/net/cxgb3/adapter.h
+++ b/drivers/net/cxgb3/adapter.h
@@ -92,6 +92,7 @@ struct sge_fl { /* SGE per free-buffer list state */
unsigned int gen; /* free list generation */
struct fl_pg_chunk pg_chunk;/* page chunk cache */
unsigned int use_pages; /* whether FL uses pages or sk_buffs */
+ unsigned int order; /* order of page allocations */
struct rx_desc *desc; /* address of HW Rx descriptor ring */
struct rx_sw_desc *sdesc; /* address of SW Rx descriptor ring */
dma_addr_t phys_addr; /* physical address of HW ring start */
@@ -116,12 +117,15 @@ struct sge_rspq { /* state for an SGE response queue */
unsigned int polling; /* is the queue serviced through NAPI? */
unsigned int holdoff_tmr; /* interrupt holdoff timer in 100ns */
unsigned int next_holdoff; /* holdoff time for next interrupt */
+ unsigned int rx_recycle_buf; /* whether recycling occurred
+ within current sop-eop */
struct rsp_desc *desc; /* address of HW response ring */
dma_addr_t phys_addr; /* physical address of the ring */
unsigned int cntxt_id; /* SGE context id for the response q */
spinlock_t lock; /* guards response processing */
struct sk_buff *rx_head; /* offload packet receive queue head */
struct sk_buff *rx_tail; /* offload packet receive queue tail */
+ struct sk_buff *pg_skb; /* used to build frag list in napi handler */

unsigned long offload_pkts;
unsigned long offload_bundles;
diff --git a/drivers/net/cxgb3/sge.c b/drivers/net/cxgb3/sge.c
index c619a32..d22ae2b 100644
--- a/drivers/net/cxgb3/sge.c
+++ b/drivers/net/cxgb3/sge.c
@@ -55,6 +55,9 @@
* directly.
*/
#define FL0_PG_CHUNK_SIZE 2048
+#define FL0_PG_ORDER 0
+#define FL1_PG_CHUNK_SIZE (PAGE_SIZE > 8192 ? 16384 : 8192)
+#define FL1_PG_ORDER (PAGE_SIZE > 8192 ? 0 : 1)

#define SGE_RX_DROP_THRES 16

@@ -359,7 +362,7 @@ static void free_rx_bufs(struct pci_dev *pdev, struct sge_fl *q)
}

if (q->pg_chunk.page) {
- __free_page(q->pg_chunk.page);
+ __free_pages(q->pg_chunk.page, q->order);
q->pg_chunk.page = NULL;
}
}
@@ -396,10 +399,11 @@ static inline int add_one_rx_buf(void *va, unsigned int len,
return 0;
}

-static int alloc_pg_chunk(struct sge_fl *q, struct rx_sw_desc *sd, gfp_t gfp)
+static int alloc_pg_chunk(struct sge_fl *q, struct rx_sw_desc *sd, gfp_t gfp,
+ unsigned int order)
{
if (!q->pg_chunk.page) {
- q->pg_chunk.page = alloc_page(gfp);
+ q->pg_chunk.page = alloc_pages(gfp, order);
if (unlikely(!q->pg_chunk.page))
return -ENOMEM;
q->pg_chunk.va = page_address(q->pg_chunk.page);
@@ -408,7 +412,7 @@ static int alloc_pg_chunk(struct sge_fl *q, struct rx_sw_desc *sd, gfp_t gfp)
sd->pg_chunk = q->pg_chunk;

q->pg_chunk.offset += q->buf_size;
- if (q->pg_chunk.offset == PAGE_SIZE)
+ if (q->pg_chunk.offset == (PAGE_SIZE << order))
q->pg_chunk.page = NULL;
else {
q->pg_chunk.va += q->buf_size;
@@ -439,7 +443,7 @@ static int refill_fl(struct adapter *adap, struct sge_fl *q, int n, gfp_t gfp)
int err;

if (q->use_pages) {
- if (unlikely(alloc_pg_chunk(q, sd, gfp))) {
+ if (unlikely(alloc_pg_chunk(q, sd, gfp, q->order))) {
nomem: q->alloc_failed++;
break;
}
@@ -460,7 +464,8 @@ nomem: q->alloc_failed++;
if (q->use_pages) {
if (q->pg_chunk.page) {
put_page(q->pg_chunk.page);
- __free_page(q->pg_chunk.page);
+ __free_pages(q->pg_chunk.page,
+ q->order);
q->pg_chunk.page =
sd->pg_chunk.page = NULL;
}
@@ -491,7 +496,8 @@ nomem: q->alloc_failed++;

static inline void __refill_fl(struct adapter *adap, struct sge_fl *fl)
{
- refill_fl(adap, fl, min(16U, fl->size - fl->credits), GFP_ATOMIC);
+ refill_fl(adap, fl, min(16U, fl->size - fl->credits),
+ GFP_ATOMIC | __GFP_COMP);
}

/**
@@ -766,19 +772,22 @@ use_orig_buf:
* that are page chunks rather than sk_buffs.
*/
static struct sk_buff *get_packet_pg(struct adapter *adap, struct sge_fl *fl,
- unsigned int len, unsigned int drop_thres)
+ struct sge_rspq *q, unsigned int len,
+ unsigned int drop_thres)
{
- struct sk_buff *skb = NULL;
+ struct sk_buff *newskb, *skb;
struct rx_sw_desc *sd = &fl->sdesc[fl->cidx];

- if (len <= SGE_RX_COPY_THRES) {
- skb = alloc_skb(len, GFP_ATOMIC);
- if (likely(skb != NULL)) {
- __skb_put(skb, len);
+ newskb = skb = q->pg_skb;
+
+ if (!skb && (len <= SGE_RX_COPY_THRES)) {
+ newskb = alloc_skb(len, GFP_ATOMIC);
+ if (likely(newskb != NULL)) {
+ __skb_put(newskb, len);
pci_dma_sync_single_for_cpu(adap->pdev,
pci_unmap_addr(sd, dma_addr), len,
PCI_DMA_FROMDEVICE);
- memcpy(skb->data, sd->pg_chunk.va, len);
+ memcpy(newskb->data, sd->pg_chunk.va, len);
pci_dma_sync_single_for_device(adap->pdev,
pci_unmap_addr(sd, dma_addr), len,
PCI_DMA_FROMDEVICE);
@@ -787,14 +796,16 @@ static struct sk_buff *get_packet_pg(struct adapter *adap, struct sge_fl *fl,
recycle:
fl->credits--;
recycle_rx_buf(adap, fl, fl->cidx);
- return skb;
+ q->rx_recycle_buf++;
+ return newskb;
}

- if (unlikely(fl->credits <= drop_thres))
+ if (unlikely(q->rx_recycle_buf || (!skb && fl->credits <= drop_thres)))
goto recycle;

- skb = alloc_skb(SGE_RX_PULL_LEN, GFP_ATOMIC);
- if (unlikely(!skb)) {
+ if (!skb)
+ newskb = alloc_skb(SGE_RX_PULL_LEN, GFP_ATOMIC);
+ if (unlikely(!newskb)) {
if (!drop_thres)
return NULL;
goto recycle;
@@ -802,21 +813,29 @@ recycle:

pci_unmap_single(adap->pdev, pci_unmap_addr(sd, dma_addr),
fl->buf_size, PCI_DMA_FROMDEVICE);
- __skb_put(skb, SGE_RX_PULL_LEN);
- memcpy(skb->data, sd->pg_chunk.va, SGE_RX_PULL_LEN);
- skb_fill_page_desc(skb, 0, sd->pg_chunk.page,
- sd->pg_chunk.offset + SGE_RX_PULL_LEN,
- len - SGE_RX_PULL_LEN);
- skb->len = len;
- skb->data_len = len - SGE_RX_PULL_LEN;
- skb->truesize += skb->data_len;
+ if (!skb) {
+ __skb_put(newskb, SGE_RX_PULL_LEN);
+ memcpy(newskb->data, sd->pg_chunk.va, SGE_RX_PULL_LEN);
+ skb_fill_page_desc(newskb, 0, sd->pg_chunk.page,
+ sd->pg_chunk.offset + SGE_RX_PULL_LEN,
+ len - SGE_RX_PULL_LEN);
+ newskb->len = len;
+ newskb->data_len = len - SGE_RX_PULL_LEN;
+ } else {
+ skb_fill_page_desc(newskb, skb_shinfo(newskb)->nr_frags,
+ sd->pg_chunk.page,
+ sd->pg_chunk.offset, len);
+ newskb->len += len;
+ newskb->data_len += len;
+ }
+ newskb->truesize += newskb->data_len;

fl->credits--;
/*
* We do not refill FLs here, we let the caller do it to overlap a
* prefetch.
*/
- return skb;
+ return newskb;
}

/**
@@ -1973,6 +1992,12 @@ static inline int is_new_response(const struct rsp_desc *r,
return (r->intr_gen & F_RSPD_GEN2) == q->gen;
}

+static inline void clear_rspq_bufstate(struct sge_rspq * const q)
+{
+ q->pg_skb = NULL;
+ q->rx_recycle_buf = 0;
+}
+
#define RSPD_GTS_MASK (F_RSPD_TXQ0_GTS | F_RSPD_TXQ1_GTS)
#define RSPD_CTRL_MASK (RSPD_GTS_MASK | \
V_RSPD_TXQ0_CR(M_RSPD_TXQ0_CR) | \
@@ -2010,10 +2035,11 @@ static int process_responses(struct adapter *adap, struct sge_qset *qs,
q->next_holdoff = q->holdoff_tmr;

while (likely(budget_left && is_new_response(r, q))) {
- int eth, ethpad = 2;
+ int packet_complete, eth, ethpad = 2;
struct sk_buff *skb = NULL;
u32 len, flags = ntohl(r->flags);
- __be32 rss_hi = *(const __be32 *)r, rss_lo = r->rss_hdr.rss_hash_val;
+ __be32 rss_hi = *(const __be32 *)r,
+ rss_lo = r->rss_hdr.rss_hash_val;

eth = r->rss_hdr.opcode == CPL_RX_PKT;

@@ -2051,8 +2077,11 @@ no_mem:
#endif
__refill_fl(adap, fl);

- skb = get_packet_pg(adap, fl, G_RSPD_LEN(len),
- eth ? SGE_RX_DROP_THRES : 0);
+ skb = get_packet_pg(adap, fl, q,
+ G_RSPD_LEN(len),
+ eth ?
+ SGE_RX_DROP_THRES : 0);
+ q->pg_skb = skb;
} else
skb = get_packet(adap, fl, G_RSPD_LEN(len),
eth ? SGE_RX_DROP_THRES : 0);
@@ -2086,7 +2115,11 @@ no_mem:
q->credits = 0;
}

- if (likely(skb != NULL)) {
+ packet_complete = flags &
+ (F_RSPD_EOP | F_RSPD_IMM_DATA_VALID |
+ F_RSPD_ASYNC_NOTIF);
+
+ if (skb != NULL && packet_complete) {
if (eth)
rx_eth(adap, q, skb, ethpad);
else {
@@ -2098,6 +2131,9 @@ no_mem:
offload_skbs,
ngathered);
}
+
+ if (flags & F_RSPD_EOP)
+ clear_rspq_bufstate(q);
}
--budget_left;
}
@@ -2713,10 +2749,18 @@ int t3_sge_alloc_qset(struct adapter *adapter, unsigned int id, int nports,
#else
q->fl[0].buf_size = SGE_RX_SM_BUF_SIZE + sizeof(struct cpl_rx_data);
#endif
- q->fl[0].use_pages = FL0_PG_CHUNK_SIZE > 0;
+#if FL1_PG_CHUNK_SIZE > 0
+ q->fl[1].buf_size = FL1_PG_CHUNK_SIZE;
+#else
q->fl[1].buf_size = is_offload(adapter) ?
(16 * 1024) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) :
MAX_FRAME_SIZE + 2 + sizeof(struct cpl_rx_pkt);
+#endif
+
+ q->fl[0].use_pages = FL0_PG_CHUNK_SIZE > 0;
+ q->fl[1].use_pages = FL1_PG_CHUNK_SIZE > 0;
+ q->fl[0].order = FL0_PG_ORDER;
+ q->fl[1].order = FL1_PG_ORDER;

spin_lock_irq(&adapter->sge.reg_lock);

@@ -2767,7 +2811,8 @@ int t3_sge_alloc_qset(struct adapter *adapter, unsigned int id, int nports,
q->adap = adapter;
q->netdev = dev;
t3_update_qset_coalesce(q, p);
- avail = refill_fl(adapter, &q->fl[0], q->fl[0].size, GFP_KERNEL);
+ avail = refill_fl(adapter, &q->fl[0], q->fl[0].size,
+ GFP_KERNEL | __GFP_COMP);
if (!avail) {
CH_ALERT(adapter, "free list queue 0 initialization failed\n");
goto err;
@@ -2776,7 +2821,8 @@ int t3_sge_alloc_qset(struct adapter *adapter, unsigned int id, int nports,
CH_WARN(adapter, "free list queue 0 enabled with %d credits\n",
avail);

- avail = refill_fl(adapter, &q->fl[1], q->fl[1].size, GFP_KERNEL);
+ avail = refill_fl(adapter, &q->fl[1], q->fl[1].size,
+ GFP_KERNEL | __GFP_COMP);
if (avail < q->fl[1].size)
CH_WARN(adapter, "free list queue 1 enabled with %d credits\n",
avail);
@@ -2912,7 +2958,7 @@ void t3_sge_prep(struct adapter *adap, struct sge_params *p)
q->coalesce_usecs = 5;
q->rspq_size = 1024;
q->fl_size = 1024;
- q->jumbo_size = 512;
+ q->jumbo_size = 512;
q->txq_size[TXQ_ETH] = 1024;
q->txq_size[TXQ_OFLD] = 1024;
q->txq_size[TXQ_CTRL] = 256;
--
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