u8 avail; /* flag used in multilink stuff */
u8 had_frag; /* >= 1 fragments have been sent */
u32 lastseq; /* MP: last sequence # received */
+ int speed; /* speed of the corresponding ppp channel*/
#endif /* CONFIG_PPP_MULTILINK */
};
*/
static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb)
{
- int len, fragsize;
- int i, bits, hdrlen, mtu;
- int flen;
- int navail, nfree;
- int nbigger;
+ int len, totlen;
+ int i, bits, hdrlen, mtu;
+ int flen;
+ int navail, nfree, nzero;
+ int nbigger;
+ int totspeed;
+ int totfree;
unsigned char *p, *q;
struct list_head *list;
struct channel *pch;
struct sk_buff *frag;
struct ppp_channel *chan;
- nfree = 0; /* # channels which have no packet already queued */
+ totspeed = 0; /*total bitrate of the bundle*/
+ nfree = 0; /* # channels which have no packet already queued */
navail = 0; /* total # of usable channels (not deregistered) */
+ nzero = 0; /* number of channels with zero speed associated*/
+ totfree = 0; /*total # of channels available and
+ *having no queued packets before
+ *starting the fragmentation*/
+
hdrlen = (ppp->flags & SC_MP_XSHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN;
- i = 0;
- list_for_each_entry(pch, &ppp->channels, clist) {
+ i = 0;
+ list_for_each_entry(pch, &ppp->channels, clist) {
navail += pch->avail = (pch->chan != NULL);
- if (pch->avail) {
+ pch->speed = pch->chan->speed;
+ if (pch->avail) {
if (skb_queue_empty(&pch->file.xq) ||
- !pch->had_frag) {
- pch->avail = 2;
- ++nfree;
- }
- if (!pch->had_frag && i < ppp->nxchan)
- ppp->nxchan = i;
+ !pch->had_frag) {
+ if (pch->speed == 0)
+ nzero++;
+ else
+ totspeed += pch->speed;
+
+ pch->avail = 2;
+ ++nfree;
+ ++totfree;
+ }
+ if (!pch->had_frag && i < ppp->nxchan)
+ ppp->nxchan = i;
}
++i;
}
-
/*
- * Don't start sending this packet unless at least half of
- * the channels are free. This gives much better TCP
- * performance if we have a lot of channels.
+ * Don't start sending this packet unless at least half of
+ * the channels are free. This gives much better TCP
+ * performance if we have a lot of channels.
*/
- if (nfree == 0 || nfree < navail / 2)
- return 0; /* can't take now, leave it in xmit_pending */
+ if (nfree == 0 || nfree < navail / 2)
+ return 0; /* can't take now, leave it in xmit_pending */
/* Do protocol field compression (XXX this should be optional) */
- p = skb->data;
- len = skb->len;
+ p = skb->data;
+ len = skb->len;
if (*p == 0) {
++p;
--len;
}
- /*
- * Decide on fragment size.
- * We create a fragment for each free channel regardless of
- * how small they are (i.e. even 0 length) in order to minimize
- * the time that it will take to detect when a channel drops
- * a fragment.
- */
- fragsize = len;
- if (nfree > 1)
- fragsize = DIV_ROUND_UP(fragsize, nfree);
- /* nbigger channels get fragsize bytes, the rest get fragsize-1,
- except if nbigger==0, then they all get fragsize. */
- nbigger = len % nfree;
-
- /* skip to the channel after the one we last used
- and start at that one */
+ totlen = len;
+ nbigger = len % nfree;
+
+ /* skip to the channel after the one we last used
+ and start at that one */
list = &ppp->channels;
- for (i = 0; i < ppp->nxchan; ++i) {
+ for (i = 0; i < ppp->nxchan; ++i) {
list = list->next;
- if (list == &ppp->channels) {
- i = 0;
+ if (list == &ppp->channels) {
+ i = 0;
break;
}
}
- /* create a fragment for each channel */
+ /* create a fragment for each channel */
bits = B;
- while (nfree > 0 || len > 0) {
+ while (nfree > 0 && len > 0) {
list = list->next;
- if (list == &ppp->channels) {
- i = 0;
+ if (list == &ppp->channels) {
+ i = 0;
continue;
}
- pch = list_entry(list, struct channel, clist);
+ pch = list_entry(list, struct channel, clist);
++i;
if (!pch->avail)
continue;
/*
- * Skip this channel if it has a fragment pending already and
- * we haven't given a fragment to all of the free channels.
+ * Skip this channel if it has a fragment pending already and
+ * we haven't given a fragment to all of the free channels.
*/
if (pch->avail == 1) {
- if (nfree > 0)
+ if (nfree > 0)
continue;
} else {
- --nfree;
pch->avail = 1;
}
/* check the channel's mtu and whether it is still attached. */
spin_lock_bh(&pch->downl);
if (pch->chan == NULL) {
- /* can't use this channel, it's being deregistered */
+ /* can't use this channel, it's being deregistered */
+ if (pch->speed == 0)
+ nzero--;
+ else
+ totspeed -= pch->speed;
+
spin_unlock_bh(&pch->downl);
pch->avail = 0;
- if (--navail == 0)
+ totlen = len;
+ totfree--;
+ nfree--;
+ if (--navail == 0)
break;
continue;
}
/*
- * Create a fragment for this channel of
- * min(max(mtu+2-hdrlen, 4), fragsize, len) bytes.
- * If mtu+2-hdrlen < 4, that is a ridiculously small
- * MTU, so we use mtu = 2 + hdrlen.
+ *if the channel speed is not set divide
+ *the packet evenly among the free channels;
+ *otherwise divide it according to the speed
+ *of the channel we are going to transmit on
+ */
+ if (pch->speed == 0) {
+ flen = totlen/nfree ;
+ if (nbigger > 0) {
+ flen++;
+ nbigger--;
+ }
+ } else {
+ flen = (((totfree - nzero)*(totlen + hdrlen*totfree)) /
+ ((totspeed*totfree)/pch->speed)) - hdrlen;
+ if (nbigger > 0) {
+ flen += ((totfree - nzero)*pch->speed)/totspeed;
+ nbigger -= ((totfree - nzero)*pch->speed)/
+ totspeed;
+ }
+ }
+ nfree--;
+
+ /*
+ *check if we are on the last channel or
+ *we exceded the lenght of the data to
+ *fragment
+ */
+ if ((nfree == 0) || (flen > len))
+ flen = len;
+ /*
+ *it is not worth to tx on slow channels:
+ *in that case from the resulting flen according to the
+ *above formula will be equal or less than zero.
+ *Skip the channel in this case
*/
- if (fragsize > len)
- fragsize = len;
- flen = fragsize;
- mtu = pch->chan->mtu + 2 - hdrlen;
- if (mtu < 4)
- mtu = 4;
+ if (flen <= 0) {
+ pch->avail = 2;
+ spin_unlock_bh(&pch->downl);
+ continue;
+ }
+
+ mtu = pch->chan->mtu + 2 - hdrlen;
+ if (mtu < 4)
+ mtu = 4;
if (flen > mtu)
flen = mtu;
- if (flen == len && nfree == 0)
- bits |= E;
- frag = alloc_skb(flen + hdrlen + (flen == 0), GFP_ATOMIC);
+ if (flen == len)
+ bits |= E;
+ frag = alloc_skb(flen + hdrlen + (flen == 0), GFP_ATOMIC);
if (!frag)
goto noskb;
- q = skb_put(frag, flen + hdrlen);
+ q = skb_put(frag, flen + hdrlen);
- /* make the MP header */
+ /* make the MP header */
q[0] = PPP_MP >> 8;
q[1] = PPP_MP;
if (ppp->flags & SC_MP_XSHORTSEQ) {
- q[2] = bits + ((ppp->nxseq >> 8) & 0xf);
+ q[2] = bits + ((ppp->nxseq >> 8) & 0xf);
q[3] = ppp->nxseq;
} else {
q[2] = bits;
q[5] = ppp->nxseq;
}
- /*
- * Copy the data in.
- * Unfortunately there is a bug in older versions of
- * the Linux PPP multilink reconstruction code where it
- * drops 0-length fragments. Therefore we make sure the
- * fragment has at least one byte of data. Any bytes
- * we add in this situation will end up as padding on the
- * end of the reconstructed packet.
- */
- if (flen == 0)
- *skb_put(frag, 1) = 0;
- else
- memcpy(q + hdrlen, p, flen);
+ memcpy(q + hdrlen, p, flen);
/* try to send it down the channel */
chan = pch->chan;
- if (!skb_queue_empty(&pch->file.xq) ||
- !chan->ops->start_xmit(chan, frag))
+ if (!skb_queue_empty(&pch->file.xq) ||
+ !chan->ops->start_xmit(chan, frag))
skb_queue_tail(&pch->file.xq, frag);
- pch->had_frag = 1;
+ pch->had_frag = 1;
p += flen;
- len -= flen;
+ len -= flen;
++ppp->nxseq;
bits = 0;
spin_unlock_bh(&pch->downl);
-
- if (--nbigger == 0 && fragsize > 0)
- --fragsize;
}
- ppp->nxchan = i;
+ ppp->nxchan = i;
return 1;
noskb:
spin_unlock_bh(&pch->downl);
if (ppp->debug & 1)
- printk(KERN_ERR "PPP: no memory (fragment)\n");
+ printk(KERN_ERR "PPP: no memory (fragment)\n");
++ppp->dev->stats.tx_errors;
++ppp->nxseq;
return 1; /* abandon the frame */
git://bbs.cooldavid.org / net-next-2.6.git / commitdiff