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bnx2x: avoid atomic allocations during initialization 

During initialization bnx2x allocates significant amounts of memory
(for rx data, rx SGEs, TPA pool) using atomic allocations.

I received a report where bnx2x failed to allocate SGEs and it had
to fall back to TPA-less operation.

Let's use GFP_KERNEL allocations during initialization, which runs
in process context. Add gfp_t parameters to functions that are used
both in initialization and in the receive path.

Use an unlikely branch in bnx2x_frag_alloc() to avoid atomic allocation
by netdev_alloc_frag(). The branch is taken several thousands of times
during initialization, but then never more. Note that fp->rx_frag_size
is never greater than PAGE_SIZE, so __get_free_page() can be used here.

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Michal Schmidt 2013-09-05 22:13:09 +02:00 committed by David S. Miller
parent c19d65c95c
commit 996dedbafe
1 changed files with 24 additions and 16 deletions
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40
drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
View File

@ -490,10 +490,10 @@ static void bnx2x_set_gro_params(struct sk_buff *skb, u16 parsing_flags,
NAPI_GRO_CB(skb)->count = num_of_coalesced_segs;
}
static int bnx2x_alloc_rx_sge(struct bnx2x *bp,
struct bnx2x_fastpath *fp, u16 index)
static int bnx2x_alloc_rx_sge(struct bnx2x *bp, struct bnx2x_fastpath *fp,
u16 index, gfp_t gfp_mask)
{
struct page *page = alloc_pages(GFP_ATOMIC, PAGES_PER_SGE_SHIFT);
struct page *page = alloc_pages(gfp_mask, PAGES_PER_SGE_SHIFT);
struct sw_rx_page *sw_buf = &fp->rx_page_ring[index];
struct eth_rx_sge *sge = &fp->rx_sge_ring[index];
dma_addr_t mapping;
@ -572,7 +572,7 @@ static int bnx2x_fill_frag_skb(struct bnx2x *bp, struct bnx2x_fastpath *fp,
/* If we fail to allocate a substitute page, we simply stop
where we are and drop the whole packet */
err = bnx2x_alloc_rx_sge(bp, fp, sge_idx);
err = bnx2x_alloc_rx_sge(bp, fp, sge_idx, GFP_ATOMIC);
if (unlikely(err)) {
bnx2x_fp_qstats(bp, fp)->rx_skb_alloc_failed++;
return err;
@ -616,12 +616,17 @@ static void bnx2x_frag_free(const struct bnx2x_fastpath *fp, void *data)
kfree(data);
}
static void *bnx2x_frag_alloc(const struct bnx2x_fastpath *fp)
static void *bnx2x_frag_alloc(const struct bnx2x_fastpath *fp, gfp_t gfp_mask)
{
if (fp->rx_frag_size)
return netdev_alloc_frag(fp->rx_frag_size);
if (fp->rx_frag_size) {
/* GFP_KERNEL allocations are used only during initialization */
if (unlikely(gfp_mask & __GFP_WAIT))
return (void *)__get_free_page(gfp_mask);
return kmalloc(fp->rx_buf_size + NET_SKB_PAD, GFP_ATOMIC);
return netdev_alloc_frag(fp->rx_frag_size);
}
return kmalloc(fp->rx_buf_size + NET_SKB_PAD, gfp_mask);
}
#ifdef CONFIG_INET
@ -701,7 +706,7 @@ static void bnx2x_tpa_stop(struct bnx2x *bp, struct bnx2x_fastpath *fp,
goto drop;
/* Try to allocate the new data */
new_data = bnx2x_frag_alloc(fp);
new_data = bnx2x_frag_alloc(fp, GFP_ATOMIC);
/* Unmap skb in the pool anyway, as we are going to change
pool entry status to BNX2X_TPA_STOP even if new skb allocation
fails. */
@ -752,15 +757,15 @@ drop:
bnx2x_fp_stats(bp, fp)->eth_q_stats.rx_skb_alloc_failed++;
}
static int bnx2x_alloc_rx_data(struct bnx2x *bp,
struct bnx2x_fastpath *fp, u16 index)
static int bnx2x_alloc_rx_data(struct bnx2x *bp, struct bnx2x_fastpath *fp,
u16 index, gfp_t gfp_mask)
{
u8 *data;
struct sw_rx_bd *rx_buf = &fp->rx_buf_ring[index];
struct eth_rx_bd *rx_bd = &fp->rx_desc_ring[index];
dma_addr_t mapping;
data = bnx2x_frag_alloc(fp);
data = bnx2x_frag_alloc(fp, gfp_mask);
if (unlikely(data == NULL))
return -ENOMEM;
@ -953,7 +958,8 @@ int bnx2x_rx_int(struct bnx2x_fastpath *fp, int budget)
memcpy(skb->data, data + pad, len);
bnx2x_reuse_rx_data(fp, bd_cons, bd_prod);
} else {
if (likely(bnx2x_alloc_rx_data(bp, fp, bd_prod) == 0)) {
if (likely(bnx2x_alloc_rx_data(bp, fp, bd_prod,
GFP_ATOMIC) == 0)) {
dma_unmap_single(&bp->pdev->dev,
dma_unmap_addr(rx_buf, mapping),
fp->rx_buf_size,
@ -1313,7 +1319,8 @@ void bnx2x_init_rx_rings(struct bnx2x *bp)
struct sw_rx_bd *first_buf =
&tpa_info->first_buf;
first_buf->data = bnx2x_frag_alloc(fp);
first_buf->data =
bnx2x_frag_alloc(fp, GFP_KERNEL);
if (!first_buf->data) {
BNX2X_ERR("Failed to allocate TPA skb pool for queue[%d] - disabling TPA on this queue!\n",
j);
@ -1335,7 +1342,8 @@ void bnx2x_init_rx_rings(struct bnx2x *bp)
for (i = 0, ring_prod = 0;
i < MAX_RX_SGE_CNT*NUM_RX_SGE_PAGES; i++) {
if (bnx2x_alloc_rx_sge(bp, fp, ring_prod) < 0) {
if (bnx2x_alloc_rx_sge(bp, fp, ring_prod,
GFP_KERNEL) < 0) {
BNX2X_ERR("was only able to allocate %d rx sges\n",
i);
BNX2X_ERR("disabling TPA for queue[%d]\n",
@ -4221,7 +4229,7 @@ static int bnx2x_alloc_rx_bds(struct bnx2x_fastpath *fp,
* fp->eth_q_stats.rx_skb_alloc_failed = 0
*/
for (i = 0; i < rx_ring_size; i++) {
if (bnx2x_alloc_rx_data(bp, fp, ring_prod) < 0) {
if (bnx2x_alloc_rx_data(bp, fp, ring_prod, GFP_KERNEL) < 0) {
failure_cnt++;
continue;
}