Return to sch_red.c CVS log

Up to [Development] / linux-2.6-xfs / net / sched

Update 2.6.x-xfs to 2.6.23-rc4.

Also update fs/xfs with external mainline changes.
There were 12 such missing commits that I detected:

--------
commit ad690ef9e690f6c31f7d310b09ef1314bcec9033
Author: Al Viro <viro@ftp.linux.org.uk>
    xfs ioctl __user annotations

commit 20c2df83d25c6a95affe6157a4c9cac4cf5ffaac
Author: Paul Mundt <lethal@linux-sh.org>
    mm: Remove slab destructors from kmem_cache_create().

commit d0217ac04ca6591841e5665f518e38064f4e65bd
Author: Nick Piggin <npiggin@suse.de>
    mm: fault feedback #1

commit 54cb8821de07f2ffcd28c380ce9b93d5784b40d7
Author: Nick Piggin <npiggin@suse.de>
    mm: merge populate and nopage into fault (fixes nonlinear)

commit d00806b183152af6d24f46f0c33f14162ca1262a
Author: Nick Piggin <npiggin@suse.de>
    mm: fix fault vs invalidate race for linear mappings

commit a569425512253992cc64ebf8b6d00a62f986db3e
Author: Christoph Hellwig <hch@infradead.org>
    knfsd: exportfs: add exportfs.h header

commit 831441862956fffa17b9801db37e6ea1650b0f69
Author: Rafael J. Wysocki <rjw@sisk.pl>
    Freezer: make kernel threads nonfreezable by default

commit 8e1f936b73150f5095448a0fee6d4f30a1f9001d
Author: Rusty Russell <rusty@rustcorp.com.au>
    mm: clean up and kernelify shrinker registration

commit 5ffc4ef45b3b0a57872f631b4e4ceb8ace0d7496
Author: Jens Axboe <jens.axboe@oracle.com>
    sendfile: remove .sendfile from filesystems that use generic_file_sendfile()

commit 8bb7844286fb8c9fce6f65d8288aeb09d03a5e0d
Author: Rafael J. Wysocki <rjw@sisk.pl>
    Add suspend-related notifications for CPU hotplug

commit 59c51591a0ac7568824f541f57de967e88adaa07
Author: Michael Opdenacker <michael@free-electrons.com>
    Fix occurrences of "the the "

commit 0ceb331433e8aad9c5f441a965d7c681f8b9046f
Author: Dmitriy Monakhov <dmonakhov@openvz.org>
    mm: move common segment checks to separate helper function
--------
Merge of 2.6.x-xfs-melb:linux:29656b by kenmcd.

/*
 * net/sched/sch_red.c	Random Early Detection queue.
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 *
 * Changes:
 * J Hadi Salim 980914:	computation fixes
 * Alexey Makarenko <makar@phoenix.kharkov.ua> 990814: qave on idle link was calculated incorrectly.
 * J Hadi Salim 980816:  ECN support
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <net/pkt_sched.h>
#include <net/inet_ecn.h>
#include <net/red.h>


/*	Parameters, settable by user:
	-----------------------------

	limit		- bytes (must be > qth_max + burst)

	Hard limit on queue length, should be chosen >qth_max
	to allow packet bursts. This parameter does not
	affect the algorithms behaviour and can be chosen
	arbitrarily high (well, less than ram size)
	Really, this limit will never be reached
	if RED works correctly.
 */

struct red_sched_data
{
	u32			limit;		/* HARD maximal queue length */
	unsigned char		flags;
	struct red_parms	parms;
	struct red_stats	stats;
	struct Qdisc		*qdisc;
};

static inline int red_use_ecn(struct red_sched_data *q)
{
	return q->flags & TC_RED_ECN;
}

static inline int red_use_harddrop(struct red_sched_data *q)
{
	return q->flags & TC_RED_HARDDROP;
}

static int red_enqueue(struct sk_buff *skb, struct Qdisc* sch)
{
	struct red_sched_data *q = qdisc_priv(sch);
	struct Qdisc *child = q->qdisc;
	int ret;

	q->parms.qavg = red_calc_qavg(&q->parms, child->qstats.backlog);

	if (red_is_idling(&q->parms))
		red_end_of_idle_period(&q->parms);

	switch (red_action(&q->parms, q->parms.qavg)) {
		case RED_DONT_MARK:
			break;

		case RED_PROB_MARK:
			sch->qstats.overlimits++;
			if (!red_use_ecn(q) || !INET_ECN_set_ce(skb)) {
				q->stats.prob_drop++;
				goto congestion_drop;
			}

			q->stats.prob_mark++;
			break;

		case RED_HARD_MARK:
			sch->qstats.overlimits++;
			if (red_use_harddrop(q) || !red_use_ecn(q) ||
			    !INET_ECN_set_ce(skb)) {
				q->stats.forced_drop++;
				goto congestion_drop;
			}

			q->stats.forced_mark++;
			break;
	}

	ret = child->enqueue(skb, child);
	if (likely(ret == NET_XMIT_SUCCESS)) {
		sch->bstats.bytes += skb->len;
		sch->bstats.packets++;
		sch->q.qlen++;
	} else {
		q->stats.pdrop++;
		sch->qstats.drops++;
	}
	return ret;

congestion_drop:
	qdisc_drop(skb, sch);
	return NET_XMIT_CN;
}

static int red_requeue(struct sk_buff *skb, struct Qdisc* sch)
{
	struct red_sched_data *q = qdisc_priv(sch);
	struct Qdisc *child = q->qdisc;
	int ret;

	if (red_is_idling(&q->parms))
		red_end_of_idle_period(&q->parms);

	ret = child->ops->requeue(skb, child);
	if (likely(ret == NET_XMIT_SUCCESS)) {
		sch->qstats.requeues++;
		sch->q.qlen++;
	}
	return ret;
}

static struct sk_buff * red_dequeue(struct Qdisc* sch)
{
	struct sk_buff *skb;
	struct red_sched_data *q = qdisc_priv(sch);
	struct Qdisc *child = q->qdisc;

	skb = child->dequeue(child);
	if (skb)
		sch->q.qlen--;
	else if (!red_is_idling(&q->parms))
		red_start_of_idle_period(&q->parms);

	return skb;
}

static unsigned int red_drop(struct Qdisc* sch)
{
	struct red_sched_data *q = qdisc_priv(sch);
	struct Qdisc *child = q->qdisc;
	unsigned int len;

	if (child->ops->drop && (len = child->ops->drop(child)) > 0) {
		q->stats.other++;
		sch->qstats.drops++;
		sch->q.qlen--;
		return len;
	}

	if (!red_is_idling(&q->parms))
		red_start_of_idle_period(&q->parms);

	return 0;
}

static void red_reset(struct Qdisc* sch)
{
	struct red_sched_data *q = qdisc_priv(sch);

	qdisc_reset(q->qdisc);
	sch->q.qlen = 0;
	red_restart(&q->parms);
}

static void red_destroy(struct Qdisc *sch)
{
	struct red_sched_data *q = qdisc_priv(sch);
	qdisc_destroy(q->qdisc);
}

static struct Qdisc *red_create_dflt(struct Qdisc *sch, u32 limit)
{
	struct Qdisc *q;
	struct rtattr *rta;
	int ret;

	q = qdisc_create_dflt(sch->dev, &bfifo_qdisc_ops,
			      TC_H_MAKE(sch->handle, 1));
	if (q) {
		rta = kmalloc(RTA_LENGTH(sizeof(struct tc_fifo_qopt)),
			      GFP_KERNEL);
		if (rta) {
			rta->rta_type = RTM_NEWQDISC;
			rta->rta_len = RTA_LENGTH(sizeof(struct tc_fifo_qopt));
			((struct tc_fifo_qopt *)RTA_DATA(rta))->limit = limit;

			ret = q->ops->change(q, rta);
			kfree(rta);

			if (ret == 0)
				return q;
		}
		qdisc_destroy(q);
	}
	return NULL;
}

static int red_change(struct Qdisc *sch, struct rtattr *opt)
{
	struct red_sched_data *q = qdisc_priv(sch);
	struct rtattr *tb[TCA_RED_MAX];
	struct tc_red_qopt *ctl;
	struct Qdisc *child = NULL;

	if (opt == NULL || rtattr_parse_nested(tb, TCA_RED_MAX, opt))
		return -EINVAL;

	if (tb[TCA_RED_PARMS-1] == NULL ||
	    RTA_PAYLOAD(tb[TCA_RED_PARMS-1]) < sizeof(*ctl) ||
	    tb[TCA_RED_STAB-1] == NULL ||
	    RTA_PAYLOAD(tb[TCA_RED_STAB-1]) < RED_STAB_SIZE)
		return -EINVAL;

	ctl = RTA_DATA(tb[TCA_RED_PARMS-1]);

	if (ctl->limit > 0) {
		child = red_create_dflt(sch, ctl->limit);
		if (child == NULL)
			return -ENOMEM;
	}

	sch_tree_lock(sch);
	q->flags = ctl->flags;
	q->limit = ctl->limit;
	if (child) {
		qdisc_tree_decrease_qlen(q->qdisc, q->qdisc->q.qlen);
		qdisc_destroy(xchg(&q->qdisc, child));
	}

	red_set_parms(&q->parms, ctl->qth_min, ctl->qth_max, ctl->Wlog,
				 ctl->Plog, ctl->Scell_log,
				 RTA_DATA(tb[TCA_RED_STAB-1]));

	if (skb_queue_empty(&sch->q))
		red_end_of_idle_period(&q->parms);

	sch_tree_unlock(sch);
	return 0;
}

static int red_init(struct Qdisc* sch, struct rtattr *opt)
{
	struct red_sched_data *q = qdisc_priv(sch);

	q->qdisc = &noop_qdisc;
	return red_change(sch, opt);
}

static int red_dump(struct Qdisc *sch, struct sk_buff *skb)
{
	struct red_sched_data *q = qdisc_priv(sch);
	struct rtattr *opts = NULL;
	struct tc_red_qopt opt = {
		.limit		= q->limit,
		.flags		= q->flags,
		.qth_min	= q->parms.qth_min >> q->parms.Wlog,
		.qth_max	= q->parms.qth_max >> q->parms.Wlog,
		.Wlog		= q->parms.Wlog,
		.Plog		= q->parms.Plog,
		.Scell_log	= q->parms.Scell_log,
	};

	opts = RTA_NEST(skb, TCA_OPTIONS);
	RTA_PUT(skb, TCA_RED_PARMS, sizeof(opt), &opt);
	return RTA_NEST_END(skb, opts);

rtattr_failure:
	return RTA_NEST_CANCEL(skb, opts);
}

static int red_dump_stats(struct Qdisc *sch, struct gnet_dump *d)
{
	struct red_sched_data *q = qdisc_priv(sch);
	struct tc_red_xstats st = {
		.early	= q->stats.prob_drop + q->stats.forced_drop,
		.pdrop	= q->stats.pdrop,
		.other	= q->stats.other,
		.marked	= q->stats.prob_mark + q->stats.forced_mark,
	};

	return gnet_stats_copy_app(d, &st, sizeof(st));
}

static int red_dump_class(struct Qdisc *sch, unsigned long cl,
			  struct sk_buff *skb, struct tcmsg *tcm)
{
	struct red_sched_data *q = qdisc_priv(sch);

	if (cl != 1)
		return -ENOENT;
	tcm->tcm_handle |= TC_H_MIN(1);
	tcm->tcm_info = q->qdisc->handle;
	return 0;
}

static int red_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
		     struct Qdisc **old)
{
	struct red_sched_data *q = qdisc_priv(sch);

	if (new == NULL)
		new = &noop_qdisc;

	sch_tree_lock(sch);
	*old = xchg(&q->qdisc, new);
	qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
	qdisc_reset(*old);
	sch_tree_unlock(sch);
	return 0;
}

static struct Qdisc *red_leaf(struct Qdisc *sch, unsigned long arg)
{
	struct red_sched_data *q = qdisc_priv(sch);
	return q->qdisc;
}

static unsigned long red_get(struct Qdisc *sch, u32 classid)
{
	return 1;
}

static void red_put(struct Qdisc *sch, unsigned long arg)
{
	return;
}

static int red_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
			    struct rtattr **tca, unsigned long *arg)
{
	return -ENOSYS;
}

static int red_delete(struct Qdisc *sch, unsigned long cl)
{
	return -ENOSYS;
}

static void red_walk(struct Qdisc *sch, struct qdisc_walker *walker)
{
	if (!walker->stop) {
		if (walker->count >= walker->skip)
			if (walker->fn(sch, 1, walker) < 0) {
				walker->stop = 1;
				return;
			}
		walker->count++;
	}
}

static struct tcf_proto **red_find_tcf(struct Qdisc *sch, unsigned long cl)
{
	return NULL;
}

static struct Qdisc_class_ops red_class_ops = {
	.graft		=	red_graft,
	.leaf		=	red_leaf,
	.get		=	red_get,
	.put		=	red_put,
	.change		=	red_change_class,
	.delete		=	red_delete,
	.walk		=	red_walk,
	.tcf_chain	=	red_find_tcf,
	.dump		=	red_dump_class,
};

static struct Qdisc_ops red_qdisc_ops = {
	.id		=	"red",
	.priv_size	=	sizeof(struct red_sched_data),
	.cl_ops		=	&red_class_ops,
	.enqueue	=	red_enqueue,
	.dequeue	=	red_dequeue,
	.requeue	=	red_requeue,
	.drop		=	red_drop,
	.init		=	red_init,
	.reset		=	red_reset,
	.destroy	=	red_destroy,
	.change		=	red_change,
	.dump		=	red_dump,
	.dump_stats	=	red_dump_stats,
	.owner		=	THIS_MODULE,
};

static int __init red_module_init(void)
{
	return register_qdisc(&red_qdisc_ops);
}

static void __exit red_module_exit(void)
{
	unregister_qdisc(&red_qdisc_ops);
}

module_init(red_module_init)
module_exit(red_module_exit)

MODULE_LICENSE("GPL");