diff options
Diffstat (limited to 'package/kernel/mac80211/patches/606-rt2x00_no_realign.patch')
| -rw-r--r-- | package/kernel/mac80211/patches/606-rt2x00_no_realign.patch | 67 |
1 files changed, 0 insertions, 67 deletions
diff --git a/package/kernel/mac80211/patches/606-rt2x00_no_realign.patch b/package/kernel/mac80211/patches/606-rt2x00_no_realign.patch deleted file mode 100644 index 7e321922f1..0000000000 --- a/package/kernel/mac80211/patches/606-rt2x00_no_realign.patch +++ /dev/null @@ -1,67 +0,0 @@ -[RFC] rt2x00: For drivers that only need L2 padding don't realign frames - -Signed-off-by: Helmut Schaa <helmut.schaa@...> ---- - -Ivo, Gertjan, do you remeber by any chance why this alignment stuff was added -in the first place? Was it because of DMA restrictions? - -While doing some profiling on the rt3052 SoC I noticed that 30-40% time was -spent in memmove calls. And the culprit is the memmove aligning the payload -to a 4byte boundary since that has to move a whole bunch of data. - -Interesstingly the legacy drivers insert an l2pad between the header and the -payload but doesn't realign the payload itself to a 4-byte boundary. Hence, -I came up with this patch and indeed CPU usage improves impressively. - -Only tested on rt2800pci! - -Thanks, -Helmut - - drivers/net/wireless/rt2x00/rt2x00queue.c | 30 +++------------------------- - 1 files changed, 4 insertions(+), 26 deletions(-) - ---- a/drivers/net/wireless/rt2x00/rt2x00queue.c -+++ b/drivers/net/wireless/rt2x00/rt2x00queue.c -@@ -161,36 +161,14 @@ void rt2x00queue_align_frame(struct sk_b - void rt2x00queue_insert_l2pad(struct sk_buff *skb, unsigned int header_length) - { - unsigned int payload_length = skb->len - header_length; -- unsigned int header_align = ALIGN_SIZE(skb, 0); -- unsigned int payload_align = ALIGN_SIZE(skb, header_length); - unsigned int l2pad = payload_length ? L2PAD_SIZE(header_length) : 0; - -- /* -- * Adjust the header alignment if the payload needs to be moved more -- * than the header. -- */ -- if (payload_align > header_align) -- header_align += 4; -- -- /* There is nothing to do if no alignment is needed */ -- if (!header_align) -+ if (!l2pad) - return; - -- /* Reserve the amount of space needed in front of the frame */ -- skb_push(skb, header_align); -- -- /* -- * Move the header. -- */ -- memmove(skb->data, skb->data + header_align, header_length); -- -- /* Move the payload, if present and if required */ -- if (payload_length && payload_align) -- memmove(skb->data + header_length + l2pad, -- skb->data + header_length + l2pad + payload_align, -- payload_length); -- -- /* Trim the skb to the correct size */ -+ /* insert l2pad -> Move header */ -+ skb_push(skb, l2pad); -+ memmove(skb->data, skb->data + l2pad, header_length); - skb_trim(skb, header_length + l2pad + payload_length); - } - |