From dced3a053dd5415a7321e1ae153c96dea644da4e Mon Sep 17 00:00:00 2001 From: "Ed L. Cashin" Date: Wed, 20 Sep 2006 14:36:49 -0400 Subject: aoe: improve retransmission heuristics Add a dynamic minimum timer for better retransmission behavior. Signed-off-by: "Ed L. Cashin" Acked-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/block/aoe/aoecmd.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) (limited to 'drivers/block/aoe/aoecmd.c') diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c index 621fdbb..c0bdc1f 100644 --- a/drivers/block/aoe/aoecmd.c +++ b/drivers/block/aoe/aoecmd.c @@ -461,8 +461,15 @@ calc_rttavg(struct aoedev *d, int rtt) register long n; n = rtt; - if (n < MINTIMER) - n = MINTIMER; + if (n < 0) { + n = -rtt; + if (n < MINTIMER) + n = MINTIMER; + else if (n > MAXTIMER) + n = MAXTIMER; + d->mintimer += (n - d->mintimer) >> 1; + } else if (n < d->mintimer) + n = d->mintimer; else if (n > MAXTIMER) n = MAXTIMER; @@ -498,8 +505,10 @@ aoecmd_ata_rsp(struct sk_buff *skb) spin_lock_irqsave(&d->lock, flags); - f = getframe(d, be32_to_cpu(hin->tag)); + n = be32_to_cpu(hin->tag); + f = getframe(d, n); if (f == NULL) { + calc_rttavg(d, -tsince(n)); spin_unlock_irqrestore(&d->lock, flags); snprintf(ebuf, sizeof ebuf, "%15s e%d.%d tag=%08x@%08lx\n", @@ -724,6 +733,7 @@ aoecmd_cfg_rsp(struct sk_buff *skb) return; } d->flags |= DEVFL_PAUSE; /* force pause */ + d->mintimer = MINTIMER; d->fw_ver = be16_to_cpu(ch->fwver); /* check for already outstanding ataid */ -- cgit v1.1