iwl3945: better skb management in rx path
Steinar reported reallocations of skb->head with IPv6, leading to a warning in skb_try_coalesce() It turns out iwl3945 has several problems : 1) skb->truesize is underestimated. We really consume PAGE_SIZE bytes for a fragment, not the frame length. 2) 128 bytes of initial headroom is a bit low and forces reallocations. 3) We can avoid consuming a full page for small enough frames. Reported-by: Steinar H. Gunderson <sesse@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Paul Stewart <pstew@google.com> Acked-by: Stanislaw Gruszka <sgruszka@redhat.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
parent
c6c7788fe2
commit
45fe142cef
|
@ -475,6 +475,8 @@ il3945_is_network_packet(struct il_priv *il, struct ieee80211_hdr *header)
|
|||
}
|
||||
}
|
||||
|
||||
#define SMALL_PACKET_SIZE 256
|
||||
|
||||
static void
|
||||
il3945_pass_packet_to_mac80211(struct il_priv *il, struct il_rx_buf *rxb,
|
||||
struct ieee80211_rx_status *stats)
|
||||
|
@ -483,14 +485,13 @@ il3945_pass_packet_to_mac80211(struct il_priv *il, struct il_rx_buf *rxb,
|
|||
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)IL_RX_DATA(pkt);
|
||||
struct il3945_rx_frame_hdr *rx_hdr = IL_RX_HDR(pkt);
|
||||
struct il3945_rx_frame_end *rx_end = IL_RX_END(pkt);
|
||||
u16 len = le16_to_cpu(rx_hdr->len);
|
||||
u32 len = le16_to_cpu(rx_hdr->len);
|
||||
struct sk_buff *skb;
|
||||
__le16 fc = hdr->frame_control;
|
||||
u32 fraglen = PAGE_SIZE << il->hw_params.rx_page_order;
|
||||
|
||||
/* We received data from the HW, so stop the watchdog */
|
||||
if (unlikely
|
||||
(len + IL39_RX_FRAME_SIZE >
|
||||
PAGE_SIZE << il->hw_params.rx_page_order)) {
|
||||
if (unlikely(len + IL39_RX_FRAME_SIZE > fraglen)) {
|
||||
D_DROP("Corruption detected!\n");
|
||||
return;
|
||||
}
|
||||
|
@ -506,26 +507,32 @@ il3945_pass_packet_to_mac80211(struct il_priv *il, struct il_rx_buf *rxb,
|
|||
D_INFO("Woke queues - frame received on passive channel\n");
|
||||
}
|
||||
|
||||
skb = dev_alloc_skb(128);
|
||||
skb = dev_alloc_skb(SMALL_PACKET_SIZE);
|
||||
if (!skb) {
|
||||
IL_ERR("dev_alloc_skb failed\n");
|
||||
return;
|
||||
}
|
||||
|
||||
if (!il3945_mod_params.sw_crypto)
|
||||
il_set_decrypted_flag(il, (struct ieee80211_hdr *)rxb_addr(rxb),
|
||||
il_set_decrypted_flag(il, (struct ieee80211_hdr *)pkt,
|
||||
le32_to_cpu(rx_end->status), stats);
|
||||
|
||||
skb_add_rx_frag(skb, 0, rxb->page,
|
||||
(void *)rx_hdr->payload - (void *)pkt, len,
|
||||
len);
|
||||
|
||||
/* If frame is small enough to fit into skb->head, copy it
|
||||
* and do not consume a full page
|
||||
*/
|
||||
if (len <= SMALL_PACKET_SIZE) {
|
||||
memcpy(skb_put(skb, len), rx_hdr->payload, len);
|
||||
} else {
|
||||
skb_add_rx_frag(skb, 0, rxb->page,
|
||||
(void *)rx_hdr->payload - (void *)pkt, len,
|
||||
fraglen);
|
||||
il->alloc_rxb_page--;
|
||||
rxb->page = NULL;
|
||||
}
|
||||
il_update_stats(il, false, fc, len);
|
||||
memcpy(IEEE80211_SKB_RXCB(skb), stats, sizeof(*stats));
|
||||
|
||||
ieee80211_rx(il->hw, skb);
|
||||
il->alloc_rxb_page--;
|
||||
rxb->page = NULL;
|
||||
}
|
||||
|
||||
#define IL_DELAY_NEXT_SCAN_AFTER_ASSOC (HZ*6)
|
||||
|
|
Loading…
Reference in New Issue