diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/usb/cdc_ncm.c | 54 |
1 files changed, 42 insertions, 12 deletions
diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c index 2067743f51ca..d103a1d4fb36 100644 --- a/drivers/net/usb/cdc_ncm.c +++ b/drivers/net/usb/cdc_ncm.c @@ -89,6 +89,8 @@ static const struct cdc_ncm_stats cdc_ncm_gstrings_stats[] = { CDC_NCM_SIMPLE_STAT(rx_ntbs), }; +#define CDC_NCM_LOW_MEM_MAX_CNT 10 + static int cdc_ncm_get_sset_count(struct net_device __always_unused *netdev, int sset) { switch (sset) { @@ -1055,10 +1057,10 @@ static struct usb_cdc_ncm_ndp16 *cdc_ncm_ndp(struct cdc_ncm_ctx *ctx, struct sk_ /* align new NDP */ if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END)) - cdc_ncm_align_tail(skb, ctx->tx_ndp_modulus, 0, ctx->tx_max); + cdc_ncm_align_tail(skb, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size); /* verify that there is room for the NDP and the datagram (reserve) */ - if ((ctx->tx_max - skb->len - reserve) < ctx->max_ndp_size) + if ((ctx->tx_curr_size - skb->len - reserve) < ctx->max_ndp_size) return NULL; /* link to it */ @@ -1111,13 +1113,41 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign) /* allocate a new OUT skb */ if (!skb_out) { - skb_out = alloc_skb(ctx->tx_max, GFP_ATOMIC); + if (ctx->tx_low_mem_val == 0) { + ctx->tx_curr_size = ctx->tx_max; + skb_out = alloc_skb(ctx->tx_curr_size, GFP_ATOMIC); + /* If the memory allocation fails we will wait longer + * each time before attempting another full size + * allocation again to not overload the system + * further. + */ + if (skb_out == NULL) { + ctx->tx_low_mem_max_cnt = min(ctx->tx_low_mem_max_cnt + 1, + (unsigned)CDC_NCM_LOW_MEM_MAX_CNT); + ctx->tx_low_mem_val = ctx->tx_low_mem_max_cnt; + } + } if (skb_out == NULL) { - if (skb != NULL) { - dev_kfree_skb_any(skb); - dev->net->stats.tx_dropped++; + /* See if a very small allocation is possible. + * We will send this packet immediately and hope + * that there is more memory available later. + */ + if (skb) + ctx->tx_curr_size = max(skb->len, + (u32)USB_CDC_NCM_NTB_MIN_OUT_SIZE); + else + ctx->tx_curr_size = USB_CDC_NCM_NTB_MIN_OUT_SIZE; + skb_out = alloc_skb(ctx->tx_curr_size, GFP_ATOMIC); + + /* No allocation possible so we will abort */ + if (skb_out == NULL) { + if (skb != NULL) { + dev_kfree_skb_any(skb); + dev->net->stats.tx_dropped++; + } + goto exit_no_skb; } - goto exit_no_skb; + ctx->tx_low_mem_val--; } /* fill out the initial 16-bit NTB header */ nth16 = skb_put_zero(skb_out, sizeof(struct usb_cdc_ncm_nth16)); @@ -1148,10 +1178,10 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign) ndp16 = cdc_ncm_ndp(ctx, skb_out, sign, skb->len + ctx->tx_modulus + ctx->tx_remainder); /* align beginning of next frame */ - cdc_ncm_align_tail(skb_out, ctx->tx_modulus, ctx->tx_remainder, ctx->tx_max); + cdc_ncm_align_tail(skb_out, ctx->tx_modulus, ctx->tx_remainder, ctx->tx_curr_size); /* check if we had enough room left for both NDP and frame */ - if (!ndp16 || skb_out->len + skb->len + delayed_ndp_size > ctx->tx_max) { + if (!ndp16 || skb_out->len + skb->len + delayed_ndp_size > ctx->tx_curr_size) { if (n == 0) { /* won't fit, MTU problem? */ dev_kfree_skb_any(skb); @@ -1227,7 +1257,7 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign) /* If requested, put NDP at end of frame. */ if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) { nth16 = (struct usb_cdc_ncm_nth16 *)skb_out->data; - cdc_ncm_align_tail(skb_out, ctx->tx_ndp_modulus, 0, ctx->tx_max); + cdc_ncm_align_tail(skb_out, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size); nth16->wNdpIndex = cpu_to_le16(skb_out->len); skb_put_data(skb_out, ctx->delayed_ndp16, ctx->max_ndp_size); @@ -1246,9 +1276,9 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign) */ if (!(dev->driver_info->flags & FLAG_SEND_ZLP) && skb_out->len > ctx->min_tx_pkt) { - padding_count = ctx->tx_max - skb_out->len; + padding_count = ctx->tx_curr_size - skb_out->len; skb_put_zero(skb_out, padding_count); - } else if (skb_out->len < ctx->tx_max && + } else if (skb_out->len < ctx->tx_curr_size && (skb_out->len % dev->maxpacket) == 0) { skb_put_u8(skb_out, 0); /* force short packet */ } |