On Thu, Nov 1, 2018 at 8:08 PM Wright Feng <Wright.Feng@xxxxxxxxxxx> wrote: > > > > On 2018/10/30 上午 02:50, Franky Lin wrote: > > On Mon, Oct 29, 2018 at 3:27 AM Wright Feng <Wright.Feng@xxxxxxxxxxx> wrote: > >> > >> Linux 3.6 introduces TSQ which has a per socket threshold for TCP Tx > >> packets to reduce latency. In fcmode 1 and fcmode 2, host driver enqueues > >> skb in hanger and TCP doesn't push new skb until host frees the skb when > >> receiving fwstatus event. So using skb_orphan before sending skb to bus > >> will make the skb removing the ownership of socket. With this patch, we > >> are able to get better throughput in fcmode 1 and fcmode 2. > >> > >> Tested 43455 TCP throughput in 20 MHz bandwidth with / without this patch. > >> fcmode 0: 59.5 / 59.6 (mbps) > >> fcmode 1: 59.3 / 23.4 (mbps) > >> fcmode 2: 59.6 / 21.5 (mbps) > >> > >> Signed-off-by: Wright Feng <wright.feng@xxxxxxxxxxx> > >> --- > >> drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c | 1 + > >> 1 file changed, 1 insertion(+) > >> > >> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c > >> index b2e1ab5..519b25d 100644 > >> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c > >> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c > >> @@ -2298,6 +2298,7 @@ static uint brcmf_sdio_sendfromq(struct brcmf_sdio *bus, uint maxframes) > >> &prec_out); > >> if (pkt == NULL) > >> break; > >> + skb_orphan(pkt); > > > > TSQ allows device driver to tweak for a deeper queue now. [1]. We > > should use that instead of orphaning the packet before handing over to > > firmware which would remove the bufferbloat protection by TSQ. > > > > Thanks, > > -Franky > > > Since the aggregation problem has been fixed by setting sk_pacing_shift, > I will submit v2 without this one. > Thanks for the information. No the problem is not fixed. The patch just provides an interface sk_pacing_shift_update so the device driver can tweak the scale to allow more packets being queued. You need to call sk_pacing_shift_update somewhere in brcmfmac. Thanks, -Franky > > -Wright > > [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=3a9b76fd0db9f > > > >> __skb_queue_tail(&pktq, pkt); > >> } > >> spin_unlock_bh(&bus->txq_lock); > >> -- > >> 1.9.1 > >>
