linux/net/sched/sch_hfsc.c
Patrick McHardy e488eafcc5 [NET_SCHED]: Fix endless loops (part 5): netem/tbf/hfsc ->requeue failures
When peeking at the next packet in a child qdisc by calling dequeue/requeue,
the upper qdisc qlen counter may get out of sync in case the requeue fails.
The qdisc and the child qdisc both have their counter decremented, but since
no packet is given to the upper qdisc it won't decrement its counter itself.

requeue should not fail, so this is mostly for "correctness".

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:31:46 -08:00

1831 lines
42 KiB
C

/*
* Copyright (c) 2003 Patrick McHardy, <kaber@trash.net>
*
* 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.
*
* 2003-10-17 - Ported from altq
*/
/*
* Copyright (c) 1997-1999 Carnegie Mellon University. All Rights Reserved.
*
* Permission to use, copy, modify, and distribute this software and
* its documentation is hereby granted (including for commercial or
* for-profit use), provided that both the copyright notice and this
* permission notice appear in all copies of the software, derivative
* works, or modified versions, and any portions thereof.
*
* THIS SOFTWARE IS EXPERIMENTAL AND IS KNOWN TO HAVE BUGS, SOME OF
* WHICH MAY HAVE SERIOUS CONSEQUENCES. CARNEGIE MELLON PROVIDES THIS
* SOFTWARE IN ITS ``AS IS'' CONDITION, AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* Carnegie Mellon encourages (but does not require) users of this
* software to return any improvements or extensions that they make,
* and to grant Carnegie Mellon the rights to redistribute these
* changes without encumbrance.
*/
/*
* H-FSC is described in Proceedings of SIGCOMM'97,
* "A Hierarchical Fair Service Curve Algorithm for Link-Sharing,
* Real-Time and Priority Service"
* by Ion Stoica, Hui Zhang, and T. S. Eugene Ng.
*
* Oleg Cherevko <olwi@aq.ml.com.ua> added the upperlimit for link-sharing.
* when a class has an upperlimit, the fit-time is computed from the
* upperlimit service curve. the link-sharing scheduler does not schedule
* a class whose fit-time exceeds the current time.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/jiffies.h>
#include <linux/compiler.h>
#include <linux/spinlock.h>
#include <linux/skbuff.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/timer.h>
#include <linux/list.h>
#include <linux/rbtree.h>
#include <linux/init.h>
#include <linux/netdevice.h>
#include <linux/rtnetlink.h>
#include <linux/pkt_sched.h>
#include <net/pkt_sched.h>
#include <net/pkt_cls.h>
#include <asm/system.h>
#include <asm/div64.h>
#define HFSC_DEBUG 1
/*
* kernel internal service curve representation:
* coordinates are given by 64 bit unsigned integers.
* x-axis: unit is clock count.
* y-axis: unit is byte.
*
* The service curve parameters are converted to the internal
* representation. The slope values are scaled to avoid overflow.
* the inverse slope values as well as the y-projection of the 1st
* segment are kept in order to to avoid 64-bit divide operations
* that are expensive on 32-bit architectures.
*/
struct internal_sc
{
u64 sm1; /* scaled slope of the 1st segment */
u64 ism1; /* scaled inverse-slope of the 1st segment */
u64 dx; /* the x-projection of the 1st segment */
u64 dy; /* the y-projection of the 1st segment */
u64 sm2; /* scaled slope of the 2nd segment */
u64 ism2; /* scaled inverse-slope of the 2nd segment */
};
/* runtime service curve */
struct runtime_sc
{
u64 x; /* current starting position on x-axis */
u64 y; /* current starting position on y-axis */
u64 sm1; /* scaled slope of the 1st segment */
u64 ism1; /* scaled inverse-slope of the 1st segment */
u64 dx; /* the x-projection of the 1st segment */
u64 dy; /* the y-projection of the 1st segment */
u64 sm2; /* scaled slope of the 2nd segment */
u64 ism2; /* scaled inverse-slope of the 2nd segment */
};
enum hfsc_class_flags
{
HFSC_RSC = 0x1,
HFSC_FSC = 0x2,
HFSC_USC = 0x4
};
struct hfsc_class
{
u32 classid; /* class id */
unsigned int refcnt; /* usage count */
struct gnet_stats_basic bstats;
struct gnet_stats_queue qstats;
struct gnet_stats_rate_est rate_est;
spinlock_t *stats_lock;
unsigned int level; /* class level in hierarchy */
struct tcf_proto *filter_list; /* filter list */
unsigned int filter_cnt; /* filter count */
struct hfsc_sched *sched; /* scheduler data */
struct hfsc_class *cl_parent; /* parent class */
struct list_head siblings; /* sibling classes */
struct list_head children; /* child classes */
struct Qdisc *qdisc; /* leaf qdisc */
struct rb_node el_node; /* qdisc's eligible tree member */
struct rb_root vt_tree; /* active children sorted by cl_vt */
struct rb_node vt_node; /* parent's vt_tree member */
struct rb_root cf_tree; /* active children sorted by cl_f */
struct rb_node cf_node; /* parent's cf_heap member */
struct list_head hlist; /* hash list member */
struct list_head dlist; /* drop list member */
u64 cl_total; /* total work in bytes */
u64 cl_cumul; /* cumulative work in bytes done by
real-time criteria */
u64 cl_d; /* deadline*/
u64 cl_e; /* eligible time */
u64 cl_vt; /* virtual time */
u64 cl_f; /* time when this class will fit for
link-sharing, max(myf, cfmin) */
u64 cl_myf; /* my fit-time (calculated from this
class's own upperlimit curve) */
u64 cl_myfadj; /* my fit-time adjustment (to cancel
history dependence) */
u64 cl_cfmin; /* earliest children's fit-time (used
with cl_myf to obtain cl_f) */
u64 cl_cvtmin; /* minimal virtual time among the
children fit for link-sharing
(monotonic within a period) */
u64 cl_vtadj; /* intra-period cumulative vt
adjustment */
u64 cl_vtoff; /* inter-period cumulative vt offset */
u64 cl_cvtmax; /* max child's vt in the last period */
u64 cl_cvtoff; /* cumulative cvtmax of all periods */
u64 cl_pcvtoff; /* parent's cvtoff at initalization
time */
struct internal_sc cl_rsc; /* internal real-time service curve */
struct internal_sc cl_fsc; /* internal fair service curve */
struct internal_sc cl_usc; /* internal upperlimit service curve */
struct runtime_sc cl_deadline; /* deadline curve */
struct runtime_sc cl_eligible; /* eligible curve */
struct runtime_sc cl_virtual; /* virtual curve */
struct runtime_sc cl_ulimit; /* upperlimit curve */
unsigned long cl_flags; /* which curves are valid */
unsigned long cl_vtperiod; /* vt period sequence number */
unsigned long cl_parentperiod;/* parent's vt period sequence number*/
unsigned long cl_nactive; /* number of active children */
};
#define HFSC_HSIZE 16
struct hfsc_sched
{
u16 defcls; /* default class id */
struct hfsc_class root; /* root class */
struct list_head clhash[HFSC_HSIZE]; /* class hash */
struct rb_root eligible; /* eligible tree */
struct list_head droplist; /* active leaf class list (for
dropping) */
struct sk_buff_head requeue; /* requeued packet */
struct timer_list wd_timer; /* watchdog timer */
};
/*
* macros
*/
#ifdef CONFIG_NET_SCH_CLK_GETTIMEOFDAY
#include <linux/time.h>
#undef PSCHED_GET_TIME
#define PSCHED_GET_TIME(stamp) \
do { \
struct timeval tv; \
do_gettimeofday(&tv); \
(stamp) = 1ULL * USEC_PER_SEC * tv.tv_sec + tv.tv_usec; \
} while (0)
#endif
#if HFSC_DEBUG
#define ASSERT(cond) \
do { \
if (unlikely(!(cond))) \
printk("assertion %s failed at %s:%i (%s)\n", \
#cond, __FILE__, __LINE__, __FUNCTION__); \
} while (0)
#else
#define ASSERT(cond)
#endif /* HFSC_DEBUG */
#define HT_INFINITY 0xffffffffffffffffULL /* infinite time value */
/*
* eligible tree holds backlogged classes being sorted by their eligible times.
* there is one eligible tree per hfsc instance.
*/
static void
eltree_insert(struct hfsc_class *cl)
{
struct rb_node **p = &cl->sched->eligible.rb_node;
struct rb_node *parent = NULL;
struct hfsc_class *cl1;
while (*p != NULL) {
parent = *p;
cl1 = rb_entry(parent, struct hfsc_class, el_node);
if (cl->cl_e >= cl1->cl_e)
p = &parent->rb_right;
else
p = &parent->rb_left;
}
rb_link_node(&cl->el_node, parent, p);
rb_insert_color(&cl->el_node, &cl->sched->eligible);
}
static inline void
eltree_remove(struct hfsc_class *cl)
{
rb_erase(&cl->el_node, &cl->sched->eligible);
}
static inline void
eltree_update(struct hfsc_class *cl)
{
eltree_remove(cl);
eltree_insert(cl);
}
/* find the class with the minimum deadline among the eligible classes */
static inline struct hfsc_class *
eltree_get_mindl(struct hfsc_sched *q, u64 cur_time)
{
struct hfsc_class *p, *cl = NULL;
struct rb_node *n;
for (n = rb_first(&q->eligible); n != NULL; n = rb_next(n)) {
p = rb_entry(n, struct hfsc_class, el_node);
if (p->cl_e > cur_time)
break;
if (cl == NULL || p->cl_d < cl->cl_d)
cl = p;
}
return cl;
}
/* find the class with minimum eligible time among the eligible classes */
static inline struct hfsc_class *
eltree_get_minel(struct hfsc_sched *q)
{
struct rb_node *n;
n = rb_first(&q->eligible);
if (n == NULL)
return NULL;
return rb_entry(n, struct hfsc_class, el_node);
}
/*
* vttree holds holds backlogged child classes being sorted by their virtual
* time. each intermediate class has one vttree.
*/
static void
vttree_insert(struct hfsc_class *cl)
{
struct rb_node **p = &cl->cl_parent->vt_tree.rb_node;
struct rb_node *parent = NULL;
struct hfsc_class *cl1;
while (*p != NULL) {
parent = *p;
cl1 = rb_entry(parent, struct hfsc_class, vt_node);
if (cl->cl_vt >= cl1->cl_vt)
p = &parent->rb_right;
else
p = &parent->rb_left;
}
rb_link_node(&cl->vt_node, parent, p);
rb_insert_color(&cl->vt_node, &cl->cl_parent->vt_tree);
}
static inline void
vttree_remove(struct hfsc_class *cl)
{
rb_erase(&cl->vt_node, &cl->cl_parent->vt_tree);
}
static inline void
vttree_update(struct hfsc_class *cl)
{
vttree_remove(cl);
vttree_insert(cl);
}
static inline struct hfsc_class *
vttree_firstfit(struct hfsc_class *cl, u64 cur_time)
{
struct hfsc_class *p;
struct rb_node *n;
for (n = rb_first(&cl->vt_tree); n != NULL; n = rb_next(n)) {
p = rb_entry(n, struct hfsc_class, vt_node);
if (p->cl_f <= cur_time)
return p;
}
return NULL;
}
/*
* get the leaf class with the minimum vt in the hierarchy
*/
static struct hfsc_class *
vttree_get_minvt(struct hfsc_class *cl, u64 cur_time)
{
/* if root-class's cfmin is bigger than cur_time nothing to do */
if (cl->cl_cfmin > cur_time)
return NULL;
while (cl->level > 0) {
cl = vttree_firstfit(cl, cur_time);
if (cl == NULL)
return NULL;
/*
* update parent's cl_cvtmin.
*/
if (cl->cl_parent->cl_cvtmin < cl->cl_vt)
cl->cl_parent->cl_cvtmin = cl->cl_vt;
}
return cl;
}
static void
cftree_insert(struct hfsc_class *cl)
{
struct rb_node **p = &cl->cl_parent->cf_tree.rb_node;
struct rb_node *parent = NULL;
struct hfsc_class *cl1;
while (*p != NULL) {
parent = *p;
cl1 = rb_entry(parent, struct hfsc_class, cf_node);
if (cl->cl_f >= cl1->cl_f)
p = &parent->rb_right;
else
p = &parent->rb_left;
}
rb_link_node(&cl->cf_node, parent, p);
rb_insert_color(&cl->cf_node, &cl->cl_parent->cf_tree);
}
static inline void
cftree_remove(struct hfsc_class *cl)
{
rb_erase(&cl->cf_node, &cl->cl_parent->cf_tree);
}
static inline void
cftree_update(struct hfsc_class *cl)
{
cftree_remove(cl);
cftree_insert(cl);
}
/*
* service curve support functions
*
* external service curve parameters
* m: bps
* d: us
* internal service curve parameters
* sm: (bytes/psched_us) << SM_SHIFT
* ism: (psched_us/byte) << ISM_SHIFT
* dx: psched_us
*
* Clock source resolution (CONFIG_NET_SCH_CLK_*)
* JIFFIES: for 48<=HZ<=1534 resolution is between 0.63us and 1.27us.
* CPU: resolution is between 0.5us and 1us.
* GETTIMEOFDAY: resolution is exactly 1us.
*
* sm and ism are scaled in order to keep effective digits.
* SM_SHIFT and ISM_SHIFT are selected to keep at least 4 effective
* digits in decimal using the following table.
*
* Note: We can afford the additional accuracy (altq hfsc keeps at most
* 3 effective digits) thanks to the fact that linux clock is bounded
* much more tightly.
*
* bits/sec 100Kbps 1Mbps 10Mbps 100Mbps 1Gbps
* ------------+-------------------------------------------------------
* bytes/0.5us 6.25e-3 62.5e-3 625e-3 6250e-e 62500e-3
* bytes/us 12.5e-3 125e-3 1250e-3 12500e-3 125000e-3
* bytes/1.27us 15.875e-3 158.75e-3 1587.5e-3 15875e-3 158750e-3
*
* 0.5us/byte 160 16 1.6 0.16 0.016
* us/byte 80 8 0.8 0.08 0.008
* 1.27us/byte 63 6.3 0.63 0.063 0.0063
*/
#define SM_SHIFT 20
#define ISM_SHIFT 18
#define SM_MASK ((1ULL << SM_SHIFT) - 1)
#define ISM_MASK ((1ULL << ISM_SHIFT) - 1)
static inline u64
seg_x2y(u64 x, u64 sm)
{
u64 y;
/*
* compute
* y = x * sm >> SM_SHIFT
* but divide it for the upper and lower bits to avoid overflow
*/
y = (x >> SM_SHIFT) * sm + (((x & SM_MASK) * sm) >> SM_SHIFT);
return y;
}
static inline u64
seg_y2x(u64 y, u64 ism)
{
u64 x;
if (y == 0)
x = 0;
else if (ism == HT_INFINITY)
x = HT_INFINITY;
else {
x = (y >> ISM_SHIFT) * ism
+ (((y & ISM_MASK) * ism) >> ISM_SHIFT);
}
return x;
}
/* Convert m (bps) into sm (bytes/psched us) */
static u64
m2sm(u32 m)
{
u64 sm;
sm = ((u64)m << SM_SHIFT);
sm += PSCHED_JIFFIE2US(HZ) - 1;
do_div(sm, PSCHED_JIFFIE2US(HZ));
return sm;
}
/* convert m (bps) into ism (psched us/byte) */
static u64
m2ism(u32 m)
{
u64 ism;
if (m == 0)
ism = HT_INFINITY;
else {
ism = ((u64)PSCHED_JIFFIE2US(HZ) << ISM_SHIFT);
ism += m - 1;
do_div(ism, m);
}
return ism;
}
/* convert d (us) into dx (psched us) */
static u64
d2dx(u32 d)
{
u64 dx;
dx = ((u64)d * PSCHED_JIFFIE2US(HZ));
dx += USEC_PER_SEC - 1;
do_div(dx, USEC_PER_SEC);
return dx;
}
/* convert sm (bytes/psched us) into m (bps) */
static u32
sm2m(u64 sm)
{
u64 m;
m = (sm * PSCHED_JIFFIE2US(HZ)) >> SM_SHIFT;
return (u32)m;
}
/* convert dx (psched us) into d (us) */
static u32
dx2d(u64 dx)
{
u64 d;
d = dx * USEC_PER_SEC;
do_div(d, PSCHED_JIFFIE2US(HZ));
return (u32)d;
}
static void
sc2isc(struct tc_service_curve *sc, struct internal_sc *isc)
{
isc->sm1 = m2sm(sc->m1);
isc->ism1 = m2ism(sc->m1);
isc->dx = d2dx(sc->d);
isc->dy = seg_x2y(isc->dx, isc->sm1);
isc->sm2 = m2sm(sc->m2);
isc->ism2 = m2ism(sc->m2);
}
/*
* initialize the runtime service curve with the given internal
* service curve starting at (x, y).
*/
static void
rtsc_init(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
{
rtsc->x = x;
rtsc->y = y;
rtsc->sm1 = isc->sm1;
rtsc->ism1 = isc->ism1;
rtsc->dx = isc->dx;
rtsc->dy = isc->dy;
rtsc->sm2 = isc->sm2;
rtsc->ism2 = isc->ism2;
}
/*
* calculate the y-projection of the runtime service curve by the
* given x-projection value
*/
static u64
rtsc_y2x(struct runtime_sc *rtsc, u64 y)
{
u64 x;
if (y < rtsc->y)
x = rtsc->x;
else if (y <= rtsc->y + rtsc->dy) {
/* x belongs to the 1st segment */
if (rtsc->dy == 0)
x = rtsc->x + rtsc->dx;
else
x = rtsc->x + seg_y2x(y - rtsc->y, rtsc->ism1);
} else {
/* x belongs to the 2nd segment */
x = rtsc->x + rtsc->dx
+ seg_y2x(y - rtsc->y - rtsc->dy, rtsc->ism2);
}
return x;
}
static u64
rtsc_x2y(struct runtime_sc *rtsc, u64 x)
{
u64 y;
if (x <= rtsc->x)
y = rtsc->y;
else if (x <= rtsc->x + rtsc->dx)
/* y belongs to the 1st segment */
y = rtsc->y + seg_x2y(x - rtsc->x, rtsc->sm1);
else
/* y belongs to the 2nd segment */
y = rtsc->y + rtsc->dy
+ seg_x2y(x - rtsc->x - rtsc->dx, rtsc->sm2);
return y;
}
/*
* update the runtime service curve by taking the minimum of the current
* runtime service curve and the service curve starting at (x, y).
*/
static void
rtsc_min(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
{
u64 y1, y2, dx, dy;
u32 dsm;
if (isc->sm1 <= isc->sm2) {
/* service curve is convex */
y1 = rtsc_x2y(rtsc, x);
if (y1 < y)
/* the current rtsc is smaller */
return;
rtsc->x = x;
rtsc->y = y;
return;
}
/*
* service curve is concave
* compute the two y values of the current rtsc
* y1: at x
* y2: at (x + dx)
*/
y1 = rtsc_x2y(rtsc, x);
if (y1 <= y) {
/* rtsc is below isc, no change to rtsc */
return;
}
y2 = rtsc_x2y(rtsc, x + isc->dx);
if (y2 >= y + isc->dy) {
/* rtsc is above isc, replace rtsc by isc */
rtsc->x = x;
rtsc->y = y;
rtsc->dx = isc->dx;
rtsc->dy = isc->dy;
return;
}
/*
* the two curves intersect
* compute the offsets (dx, dy) using the reverse
* function of seg_x2y()
* seg_x2y(dx, sm1) == seg_x2y(dx, sm2) + (y1 - y)
*/
dx = (y1 - y) << SM_SHIFT;
dsm = isc->sm1 - isc->sm2;
do_div(dx, dsm);
/*
* check if (x, y1) belongs to the 1st segment of rtsc.
* if so, add the offset.
*/
if (rtsc->x + rtsc->dx > x)
dx += rtsc->x + rtsc->dx - x;
dy = seg_x2y(dx, isc->sm1);
rtsc->x = x;
rtsc->y = y;
rtsc->dx = dx;
rtsc->dy = dy;
return;
}
static void
init_ed(struct hfsc_class *cl, unsigned int next_len)
{
u64 cur_time;
PSCHED_GET_TIME(cur_time);
/* update the deadline curve */
rtsc_min(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
/*
* update the eligible curve.
* for concave, it is equal to the deadline curve.
* for convex, it is a linear curve with slope m2.
*/
cl->cl_eligible = cl->cl_deadline;
if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
cl->cl_eligible.dx = 0;
cl->cl_eligible.dy = 0;
}
/* compute e and d */
cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
eltree_insert(cl);
}
static void
update_ed(struct hfsc_class *cl, unsigned int next_len)
{
cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
eltree_update(cl);
}
static inline void
update_d(struct hfsc_class *cl, unsigned int next_len)
{
cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
}
static inline void
update_cfmin(struct hfsc_class *cl)
{
struct rb_node *n = rb_first(&cl->cf_tree);
struct hfsc_class *p;
if (n == NULL) {
cl->cl_cfmin = 0;
return;
}
p = rb_entry(n, struct hfsc_class, cf_node);
cl->cl_cfmin = p->cl_f;
}
static void
init_vf(struct hfsc_class *cl, unsigned int len)
{
struct hfsc_class *max_cl;
struct rb_node *n;
u64 vt, f, cur_time;
int go_active;
cur_time = 0;
go_active = 1;
for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
if (go_active && cl->cl_nactive++ == 0)
go_active = 1;
else
go_active = 0;
if (go_active) {
n = rb_last(&cl->cl_parent->vt_tree);
if (n != NULL) {
max_cl = rb_entry(n, struct hfsc_class,vt_node);
/*
* set vt to the average of the min and max
* classes. if the parent's period didn't
* change, don't decrease vt of the class.
*/
vt = max_cl->cl_vt;
if (cl->cl_parent->cl_cvtmin != 0)
vt = (cl->cl_parent->cl_cvtmin + vt)/2;
if (cl->cl_parent->cl_vtperiod !=
cl->cl_parentperiod || vt > cl->cl_vt)
cl->cl_vt = vt;
} else {
/*
* first child for a new parent backlog period.
* add parent's cvtmax to cvtoff to make a new
* vt (vtoff + vt) larger than the vt in the
* last period for all children.
*/
vt = cl->cl_parent->cl_cvtmax;
cl->cl_parent->cl_cvtoff += vt;
cl->cl_parent->cl_cvtmax = 0;
cl->cl_parent->cl_cvtmin = 0;
cl->cl_vt = 0;
}
cl->cl_vtoff = cl->cl_parent->cl_cvtoff -
cl->cl_pcvtoff;
/* update the virtual curve */
vt = cl->cl_vt + cl->cl_vtoff;
rtsc_min(&cl->cl_virtual, &cl->cl_fsc, vt,
cl->cl_total);
if (cl->cl_virtual.x == vt) {
cl->cl_virtual.x -= cl->cl_vtoff;
cl->cl_vtoff = 0;
}
cl->cl_vtadj = 0;
cl->cl_vtperiod++; /* increment vt period */
cl->cl_parentperiod = cl->cl_parent->cl_vtperiod;
if (cl->cl_parent->cl_nactive == 0)
cl->cl_parentperiod++;
cl->cl_f = 0;
vttree_insert(cl);
cftree_insert(cl);
if (cl->cl_flags & HFSC_USC) {
/* class has upper limit curve */
if (cur_time == 0)
PSCHED_GET_TIME(cur_time);
/* update the ulimit curve */
rtsc_min(&cl->cl_ulimit, &cl->cl_usc, cur_time,
cl->cl_total);
/* compute myf */
cl->cl_myf = rtsc_y2x(&cl->cl_ulimit,
cl->cl_total);
cl->cl_myfadj = 0;
}
}
f = max(cl->cl_myf, cl->cl_cfmin);
if (f != cl->cl_f) {
cl->cl_f = f;
cftree_update(cl);
update_cfmin(cl->cl_parent);
}
}
}
static void
update_vf(struct hfsc_class *cl, unsigned int len, u64 cur_time)
{
u64 f; /* , myf_bound, delta; */
int go_passive = 0;
if (cl->qdisc->q.qlen == 0 && cl->cl_flags & HFSC_FSC)
go_passive = 1;
for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
cl->cl_total += len;
if (!(cl->cl_flags & HFSC_FSC) || cl->cl_nactive == 0)
continue;
if (go_passive && --cl->cl_nactive == 0)
go_passive = 1;
else
go_passive = 0;
if (go_passive) {
/* no more active child, going passive */
/* update cvtmax of the parent class */
if (cl->cl_vt > cl->cl_parent->cl_cvtmax)
cl->cl_parent->cl_cvtmax = cl->cl_vt;
/* remove this class from the vt tree */
vttree_remove(cl);
cftree_remove(cl);
update_cfmin(cl->cl_parent);
continue;
}
/*
* update vt and f
*/
cl->cl_vt = rtsc_y2x(&cl->cl_virtual, cl->cl_total)
- cl->cl_vtoff + cl->cl_vtadj;
/*
* if vt of the class is smaller than cvtmin,
* the class was skipped in the past due to non-fit.
* if so, we need to adjust vtadj.
*/
if (cl->cl_vt < cl->cl_parent->cl_cvtmin) {
cl->cl_vtadj += cl->cl_parent->cl_cvtmin - cl->cl_vt;
cl->cl_vt = cl->cl_parent->cl_cvtmin;
}
/* update the vt tree */
vttree_update(cl);
if (cl->cl_flags & HFSC_USC) {
cl->cl_myf = cl->cl_myfadj + rtsc_y2x(&cl->cl_ulimit,
cl->cl_total);
#if 0
/*
* This code causes classes to stay way under their
* limit when multiple classes are used at gigabit
* speed. needs investigation. -kaber
*/
/*
* if myf lags behind by more than one clock tick
* from the current time, adjust myfadj to prevent
* a rate-limited class from going greedy.
* in a steady state under rate-limiting, myf
* fluctuates within one clock tick.
*/
myf_bound = cur_time - PSCHED_JIFFIE2US(1);
if (cl->cl_myf < myf_bound) {
delta = cur_time - cl->cl_myf;
cl->cl_myfadj += delta;
cl->cl_myf += delta;
}
#endif
}
f = max(cl->cl_myf, cl->cl_cfmin);
if (f != cl->cl_f) {
cl->cl_f = f;
cftree_update(cl);
update_cfmin(cl->cl_parent);
}
}
}
static void
set_active(struct hfsc_class *cl, unsigned int len)
{
if (cl->cl_flags & HFSC_RSC)
init_ed(cl, len);
if (cl->cl_flags & HFSC_FSC)
init_vf(cl, len);
list_add_tail(&cl->dlist, &cl->sched->droplist);
}
static void
set_passive(struct hfsc_class *cl)
{
if (cl->cl_flags & HFSC_RSC)
eltree_remove(cl);
list_del(&cl->dlist);
/*
* vttree is now handled in update_vf() so that update_vf(cl, 0, 0)
* needs to be called explicitly to remove a class from vttree.
*/
}
/*
* hack to get length of first packet in queue.
*/
static unsigned int
qdisc_peek_len(struct Qdisc *sch)
{
struct sk_buff *skb;
unsigned int len;
skb = sch->dequeue(sch);
if (skb == NULL) {
if (net_ratelimit())
printk("qdisc_peek_len: non work-conserving qdisc ?\n");
return 0;
}
len = skb->len;
if (unlikely(sch->ops->requeue(skb, sch) != NET_XMIT_SUCCESS)) {
if (net_ratelimit())
printk("qdisc_peek_len: failed to requeue\n");
qdisc_tree_decrease_qlen(sch, 1);
return 0;
}
return len;
}
static void
hfsc_purge_queue(struct Qdisc *sch, struct hfsc_class *cl)
{
unsigned int len = cl->qdisc->q.qlen;
qdisc_reset(cl->qdisc);
qdisc_tree_decrease_qlen(cl->qdisc, len);
}
static void
hfsc_adjust_levels(struct hfsc_class *cl)
{
struct hfsc_class *p;
unsigned int level;
do {
level = 0;
list_for_each_entry(p, &cl->children, siblings) {
if (p->level >= level)
level = p->level + 1;
}
cl->level = level;
} while ((cl = cl->cl_parent) != NULL);
}
static inline unsigned int
hfsc_hash(u32 h)
{
h ^= h >> 8;
h ^= h >> 4;
return h & (HFSC_HSIZE - 1);
}
static inline struct hfsc_class *
hfsc_find_class(u32 classid, struct Qdisc *sch)
{
struct hfsc_sched *q = qdisc_priv(sch);
struct hfsc_class *cl;
list_for_each_entry(cl, &q->clhash[hfsc_hash(classid)], hlist) {
if (cl->classid == classid)
return cl;
}
return NULL;
}
static void
hfsc_change_rsc(struct hfsc_class *cl, struct tc_service_curve *rsc,
u64 cur_time)
{
sc2isc(rsc, &cl->cl_rsc);
rtsc_init(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
cl->cl_eligible = cl->cl_deadline;
if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
cl->cl_eligible.dx = 0;
cl->cl_eligible.dy = 0;
}
cl->cl_flags |= HFSC_RSC;
}
static void
hfsc_change_fsc(struct hfsc_class *cl, struct tc_service_curve *fsc)
{
sc2isc(fsc, &cl->cl_fsc);
rtsc_init(&cl->cl_virtual, &cl->cl_fsc, cl->cl_vt, cl->cl_total);
cl->cl_flags |= HFSC_FSC;
}
static void
hfsc_change_usc(struct hfsc_class *cl, struct tc_service_curve *usc,
u64 cur_time)
{
sc2isc(usc, &cl->cl_usc);
rtsc_init(&cl->cl_ulimit, &cl->cl_usc, cur_time, cl->cl_total);
cl->cl_flags |= HFSC_USC;
}
static int
hfsc_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
struct rtattr **tca, unsigned long *arg)
{
struct hfsc_sched *q = qdisc_priv(sch);
struct hfsc_class *cl = (struct hfsc_class *)*arg;
struct hfsc_class *parent = NULL;
struct rtattr *opt = tca[TCA_OPTIONS-1];
struct rtattr *tb[TCA_HFSC_MAX];
struct tc_service_curve *rsc = NULL, *fsc = NULL, *usc = NULL;
u64 cur_time;
if (opt == NULL || rtattr_parse_nested(tb, TCA_HFSC_MAX, opt))
return -EINVAL;
if (tb[TCA_HFSC_RSC-1]) {
if (RTA_PAYLOAD(tb[TCA_HFSC_RSC-1]) < sizeof(*rsc))
return -EINVAL;
rsc = RTA_DATA(tb[TCA_HFSC_RSC-1]);
if (rsc->m1 == 0 && rsc->m2 == 0)
rsc = NULL;
}
if (tb[TCA_HFSC_FSC-1]) {
if (RTA_PAYLOAD(tb[TCA_HFSC_FSC-1]) < sizeof(*fsc))
return -EINVAL;
fsc = RTA_DATA(tb[TCA_HFSC_FSC-1]);
if (fsc->m1 == 0 && fsc->m2 == 0)
fsc = NULL;
}
if (tb[TCA_HFSC_USC-1]) {
if (RTA_PAYLOAD(tb[TCA_HFSC_USC-1]) < sizeof(*usc))
return -EINVAL;
usc = RTA_DATA(tb[TCA_HFSC_USC-1]);
if (usc->m1 == 0 && usc->m2 == 0)
usc = NULL;
}
if (cl != NULL) {
if (parentid) {
if (cl->cl_parent && cl->cl_parent->classid != parentid)
return -EINVAL;
if (cl->cl_parent == NULL && parentid != TC_H_ROOT)
return -EINVAL;
}
PSCHED_GET_TIME(cur_time);
sch_tree_lock(sch);
if (rsc != NULL)
hfsc_change_rsc(cl, rsc, cur_time);
if (fsc != NULL)
hfsc_change_fsc(cl, fsc);
if (usc != NULL)
hfsc_change_usc(cl, usc, cur_time);
if (cl->qdisc->q.qlen != 0) {
if (cl->cl_flags & HFSC_RSC)
update_ed(cl, qdisc_peek_len(cl->qdisc));
if (cl->cl_flags & HFSC_FSC)
update_vf(cl, 0, cur_time);
}
sch_tree_unlock(sch);
#ifdef CONFIG_NET_ESTIMATOR
if (tca[TCA_RATE-1])
gen_replace_estimator(&cl->bstats, &cl->rate_est,
cl->stats_lock, tca[TCA_RATE-1]);
#endif
return 0;
}
if (parentid == TC_H_ROOT)
return -EEXIST;
parent = &q->root;
if (parentid) {
parent = hfsc_find_class(parentid, sch);
if (parent == NULL)
return -ENOENT;
}
if (classid == 0 || TC_H_MAJ(classid ^ sch->handle) != 0)
return -EINVAL;
if (hfsc_find_class(classid, sch))
return -EEXIST;
if (rsc == NULL && fsc == NULL)
return -EINVAL;
cl = kzalloc(sizeof(struct hfsc_class), GFP_KERNEL);
if (cl == NULL)
return -ENOBUFS;
if (rsc != NULL)
hfsc_change_rsc(cl, rsc, 0);
if (fsc != NULL)
hfsc_change_fsc(cl, fsc);
if (usc != NULL)
hfsc_change_usc(cl, usc, 0);
cl->refcnt = 1;
cl->classid = classid;
cl->sched = q;
cl->cl_parent = parent;
cl->qdisc = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops, classid);
if (cl->qdisc == NULL)
cl->qdisc = &noop_qdisc;
cl->stats_lock = &sch->dev->queue_lock;
INIT_LIST_HEAD(&cl->children);
cl->vt_tree = RB_ROOT;
cl->cf_tree = RB_ROOT;
sch_tree_lock(sch);
list_add_tail(&cl->hlist, &q->clhash[hfsc_hash(classid)]);
list_add_tail(&cl->siblings, &parent->children);
if (parent->level == 0)
hfsc_purge_queue(sch, parent);
hfsc_adjust_levels(parent);
cl->cl_pcvtoff = parent->cl_cvtoff;
sch_tree_unlock(sch);
#ifdef CONFIG_NET_ESTIMATOR
if (tca[TCA_RATE-1])
gen_new_estimator(&cl->bstats, &cl->rate_est,
cl->stats_lock, tca[TCA_RATE-1]);
#endif
*arg = (unsigned long)cl;
return 0;
}
static void
hfsc_destroy_filters(struct tcf_proto **fl)
{
struct tcf_proto *tp;
while ((tp = *fl) != NULL) {
*fl = tp->next;
tcf_destroy(tp);
}
}
static void
hfsc_destroy_class(struct Qdisc *sch, struct hfsc_class *cl)
{
struct hfsc_sched *q = qdisc_priv(sch);
hfsc_destroy_filters(&cl->filter_list);
qdisc_destroy(cl->qdisc);
#ifdef CONFIG_NET_ESTIMATOR
gen_kill_estimator(&cl->bstats, &cl->rate_est);
#endif
if (cl != &q->root)
kfree(cl);
}
static int
hfsc_delete_class(struct Qdisc *sch, unsigned long arg)
{
struct hfsc_sched *q = qdisc_priv(sch);
struct hfsc_class *cl = (struct hfsc_class *)arg;
if (cl->level > 0 || cl->filter_cnt > 0 || cl == &q->root)
return -EBUSY;
sch_tree_lock(sch);
list_del(&cl->hlist);
list_del(&cl->siblings);
hfsc_adjust_levels(cl->cl_parent);
hfsc_purge_queue(sch, cl);
if (--cl->refcnt == 0)
hfsc_destroy_class(sch, cl);
sch_tree_unlock(sch);
return 0;
}
static struct hfsc_class *
hfsc_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
{
struct hfsc_sched *q = qdisc_priv(sch);
struct hfsc_class *cl;
struct tcf_result res;
struct tcf_proto *tcf;
int result;
if (TC_H_MAJ(skb->priority ^ sch->handle) == 0 &&
(cl = hfsc_find_class(skb->priority, sch)) != NULL)
if (cl->level == 0)
return cl;
*qerr = NET_XMIT_BYPASS;
tcf = q->root.filter_list;
while (tcf && (result = tc_classify(skb, tcf, &res)) >= 0) {
#ifdef CONFIG_NET_CLS_ACT
switch (result) {
case TC_ACT_QUEUED:
case TC_ACT_STOLEN:
*qerr = NET_XMIT_SUCCESS;
case TC_ACT_SHOT:
return NULL;
}
#elif defined(CONFIG_NET_CLS_POLICE)
if (result == TC_POLICE_SHOT)
return NULL;
#endif
if ((cl = (struct hfsc_class *)res.class) == NULL) {
if ((cl = hfsc_find_class(res.classid, sch)) == NULL)
break; /* filter selected invalid classid */
}
if (cl->level == 0)
return cl; /* hit leaf class */
/* apply inner filter chain */
tcf = cl->filter_list;
}
/* classification failed, try default class */
cl = hfsc_find_class(TC_H_MAKE(TC_H_MAJ(sch->handle), q->defcls), sch);
if (cl == NULL || cl->level > 0)
return NULL;
return cl;
}
static int
hfsc_graft_class(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
struct Qdisc **old)
{
struct hfsc_class *cl = (struct hfsc_class *)arg;
if (cl == NULL)
return -ENOENT;
if (cl->level > 0)
return -EINVAL;
if (new == NULL) {
new = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops,
cl->classid);
if (new == NULL)
new = &noop_qdisc;
}
sch_tree_lock(sch);
hfsc_purge_queue(sch, cl);
*old = xchg(&cl->qdisc, new);
sch_tree_unlock(sch);
return 0;
}
static struct Qdisc *
hfsc_class_leaf(struct Qdisc *sch, unsigned long arg)
{
struct hfsc_class *cl = (struct hfsc_class *)arg;
if (cl != NULL && cl->level == 0)
return cl->qdisc;
return NULL;
}
static void
hfsc_qlen_notify(struct Qdisc *sch, unsigned long arg)
{
struct hfsc_class *cl = (struct hfsc_class *)arg;
if (cl->qdisc->q.qlen == 0) {
update_vf(cl, 0, 0);
set_passive(cl);
}
}
static unsigned long
hfsc_get_class(struct Qdisc *sch, u32 classid)
{
struct hfsc_class *cl = hfsc_find_class(classid, sch);
if (cl != NULL)
cl->refcnt++;
return (unsigned long)cl;
}
static void
hfsc_put_class(struct Qdisc *sch, unsigned long arg)
{
struct hfsc_class *cl = (struct hfsc_class *)arg;
if (--cl->refcnt == 0)
hfsc_destroy_class(sch, cl);
}
static unsigned long
hfsc_bind_tcf(struct Qdisc *sch, unsigned long parent, u32 classid)
{
struct hfsc_class *p = (struct hfsc_class *)parent;
struct hfsc_class *cl = hfsc_find_class(classid, sch);
if (cl != NULL) {
if (p != NULL && p->level <= cl->level)
return 0;
cl->filter_cnt++;
}
return (unsigned long)cl;
}
static void
hfsc_unbind_tcf(struct Qdisc *sch, unsigned long arg)
{
struct hfsc_class *cl = (struct hfsc_class *)arg;
cl->filter_cnt--;
}
static struct tcf_proto **
hfsc_tcf_chain(struct Qdisc *sch, unsigned long arg)
{
struct hfsc_sched *q = qdisc_priv(sch);
struct hfsc_class *cl = (struct hfsc_class *)arg;
if (cl == NULL)
cl = &q->root;
return &cl->filter_list;
}
static int
hfsc_dump_sc(struct sk_buff *skb, int attr, struct internal_sc *sc)
{
struct tc_service_curve tsc;
tsc.m1 = sm2m(sc->sm1);
tsc.d = dx2d(sc->dx);
tsc.m2 = sm2m(sc->sm2);
RTA_PUT(skb, attr, sizeof(tsc), &tsc);
return skb->len;
rtattr_failure:
return -1;
}
static inline int
hfsc_dump_curves(struct sk_buff *skb, struct hfsc_class *cl)
{
if ((cl->cl_flags & HFSC_RSC) &&
(hfsc_dump_sc(skb, TCA_HFSC_RSC, &cl->cl_rsc) < 0))
goto rtattr_failure;
if ((cl->cl_flags & HFSC_FSC) &&
(hfsc_dump_sc(skb, TCA_HFSC_FSC, &cl->cl_fsc) < 0))
goto rtattr_failure;
if ((cl->cl_flags & HFSC_USC) &&
(hfsc_dump_sc(skb, TCA_HFSC_USC, &cl->cl_usc) < 0))
goto rtattr_failure;
return skb->len;
rtattr_failure:
return -1;
}
static int
hfsc_dump_class(struct Qdisc *sch, unsigned long arg, struct sk_buff *skb,
struct tcmsg *tcm)
{
struct hfsc_class *cl = (struct hfsc_class *)arg;
unsigned char *b = skb->tail;
struct rtattr *rta = (struct rtattr *)b;
tcm->tcm_parent = cl->cl_parent ? cl->cl_parent->classid : TC_H_ROOT;
tcm->tcm_handle = cl->classid;
if (cl->level == 0)
tcm->tcm_info = cl->qdisc->handle;
RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
if (hfsc_dump_curves(skb, cl) < 0)
goto rtattr_failure;
rta->rta_len = skb->tail - b;
return skb->len;
rtattr_failure:
skb_trim(skb, b - skb->data);
return -1;
}
static int
hfsc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
struct gnet_dump *d)
{
struct hfsc_class *cl = (struct hfsc_class *)arg;
struct tc_hfsc_stats xstats;
cl->qstats.qlen = cl->qdisc->q.qlen;
xstats.level = cl->level;
xstats.period = cl->cl_vtperiod;
xstats.work = cl->cl_total;
xstats.rtwork = cl->cl_cumul;
if (gnet_stats_copy_basic(d, &cl->bstats) < 0 ||
#ifdef CONFIG_NET_ESTIMATOR
gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 ||
#endif
gnet_stats_copy_queue(d, &cl->qstats) < 0)
return -1;
return gnet_stats_copy_app(d, &xstats, sizeof(xstats));
}
static void
hfsc_walk(struct Qdisc *sch, struct qdisc_walker *arg)
{
struct hfsc_sched *q = qdisc_priv(sch);
struct hfsc_class *cl;
unsigned int i;
if (arg->stop)
return;
for (i = 0; i < HFSC_HSIZE; i++) {
list_for_each_entry(cl, &q->clhash[i], hlist) {
if (arg->count < arg->skip) {
arg->count++;
continue;
}
if (arg->fn(sch, (unsigned long)cl, arg) < 0) {
arg->stop = 1;
return;
}
arg->count++;
}
}
}
static void
hfsc_watchdog(unsigned long arg)
{
struct Qdisc *sch = (struct Qdisc *)arg;
sch->flags &= ~TCQ_F_THROTTLED;
netif_schedule(sch->dev);
}
static void
hfsc_schedule_watchdog(struct Qdisc *sch, u64 cur_time)
{
struct hfsc_sched *q = qdisc_priv(sch);
struct hfsc_class *cl;
u64 next_time = 0;
long delay;
if ((cl = eltree_get_minel(q)) != NULL)
next_time = cl->cl_e;
if (q->root.cl_cfmin != 0) {
if (next_time == 0 || next_time > q->root.cl_cfmin)
next_time = q->root.cl_cfmin;
}
ASSERT(next_time != 0);
delay = next_time - cur_time;
delay = PSCHED_US2JIFFIE(delay);
sch->flags |= TCQ_F_THROTTLED;
mod_timer(&q->wd_timer, jiffies + delay);
}
static int
hfsc_init_qdisc(struct Qdisc *sch, struct rtattr *opt)
{
struct hfsc_sched *q = qdisc_priv(sch);
struct tc_hfsc_qopt *qopt;
unsigned int i;
if (opt == NULL || RTA_PAYLOAD(opt) < sizeof(*qopt))
return -EINVAL;
qopt = RTA_DATA(opt);
sch->stats_lock = &sch->dev->queue_lock;
q->defcls = qopt->defcls;
for (i = 0; i < HFSC_HSIZE; i++)
INIT_LIST_HEAD(&q->clhash[i]);
q->eligible = RB_ROOT;
INIT_LIST_HEAD(&q->droplist);
skb_queue_head_init(&q->requeue);
q->root.refcnt = 1;
q->root.classid = sch->handle;
q->root.sched = q;
q->root.qdisc = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops,
sch->handle);
if (q->root.qdisc == NULL)
q->root.qdisc = &noop_qdisc;
q->root.stats_lock = &sch->dev->queue_lock;
INIT_LIST_HEAD(&q->root.children);
q->root.vt_tree = RB_ROOT;
q->root.cf_tree = RB_ROOT;
list_add(&q->root.hlist, &q->clhash[hfsc_hash(q->root.classid)]);
init_timer(&q->wd_timer);
q->wd_timer.function = hfsc_watchdog;
q->wd_timer.data = (unsigned long)sch;
return 0;
}
static int
hfsc_change_qdisc(struct Qdisc *sch, struct rtattr *opt)
{
struct hfsc_sched *q = qdisc_priv(sch);
struct tc_hfsc_qopt *qopt;
if (opt == NULL || RTA_PAYLOAD(opt) < sizeof(*qopt))
return -EINVAL;
qopt = RTA_DATA(opt);
sch_tree_lock(sch);
q->defcls = qopt->defcls;
sch_tree_unlock(sch);
return 0;
}
static void
hfsc_reset_class(struct hfsc_class *cl)
{
cl->cl_total = 0;
cl->cl_cumul = 0;
cl->cl_d = 0;
cl->cl_e = 0;
cl->cl_vt = 0;
cl->cl_vtadj = 0;
cl->cl_vtoff = 0;
cl->cl_cvtmin = 0;
cl->cl_cvtmax = 0;
cl->cl_cvtoff = 0;
cl->cl_pcvtoff = 0;
cl->cl_vtperiod = 0;
cl->cl_parentperiod = 0;
cl->cl_f = 0;
cl->cl_myf = 0;
cl->cl_myfadj = 0;
cl->cl_cfmin = 0;
cl->cl_nactive = 0;
cl->vt_tree = RB_ROOT;
cl->cf_tree = RB_ROOT;
qdisc_reset(cl->qdisc);
if (cl->cl_flags & HFSC_RSC)
rtsc_init(&cl->cl_deadline, &cl->cl_rsc, 0, 0);
if (cl->cl_flags & HFSC_FSC)
rtsc_init(&cl->cl_virtual, &cl->cl_fsc, 0, 0);
if (cl->cl_flags & HFSC_USC)
rtsc_init(&cl->cl_ulimit, &cl->cl_usc, 0, 0);
}
static void
hfsc_reset_qdisc(struct Qdisc *sch)
{
struct hfsc_sched *q = qdisc_priv(sch);
struct hfsc_class *cl;
unsigned int i;
for (i = 0; i < HFSC_HSIZE; i++) {
list_for_each_entry(cl, &q->clhash[i], hlist)
hfsc_reset_class(cl);
}
__skb_queue_purge(&q->requeue);
q->eligible = RB_ROOT;
INIT_LIST_HEAD(&q->droplist);
del_timer(&q->wd_timer);
sch->flags &= ~TCQ_F_THROTTLED;
sch->q.qlen = 0;
}
static void
hfsc_destroy_qdisc(struct Qdisc *sch)
{
struct hfsc_sched *q = qdisc_priv(sch);
struct hfsc_class *cl, *next;
unsigned int i;
for (i = 0; i < HFSC_HSIZE; i++) {
list_for_each_entry_safe(cl, next, &q->clhash[i], hlist)
hfsc_destroy_class(sch, cl);
}
__skb_queue_purge(&q->requeue);
del_timer(&q->wd_timer);
}
static int
hfsc_dump_qdisc(struct Qdisc *sch, struct sk_buff *skb)
{
struct hfsc_sched *q = qdisc_priv(sch);
unsigned char *b = skb->tail;
struct tc_hfsc_qopt qopt;
qopt.defcls = q->defcls;
RTA_PUT(skb, TCA_OPTIONS, sizeof(qopt), &qopt);
return skb->len;
rtattr_failure:
skb_trim(skb, b - skb->data);
return -1;
}
static int
hfsc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
{
struct hfsc_class *cl;
unsigned int len;
int err;
cl = hfsc_classify(skb, sch, &err);
if (cl == NULL) {
if (err == NET_XMIT_BYPASS)
sch->qstats.drops++;
kfree_skb(skb);
return err;
}
len = skb->len;
err = cl->qdisc->enqueue(skb, cl->qdisc);
if (unlikely(err != NET_XMIT_SUCCESS)) {
cl->qstats.drops++;
sch->qstats.drops++;
return err;
}
if (cl->qdisc->q.qlen == 1)
set_active(cl, len);
cl->bstats.packets++;
cl->bstats.bytes += len;
sch->bstats.packets++;
sch->bstats.bytes += len;
sch->q.qlen++;
return NET_XMIT_SUCCESS;
}
static struct sk_buff *
hfsc_dequeue(struct Qdisc *sch)
{
struct hfsc_sched *q = qdisc_priv(sch);
struct hfsc_class *cl;
struct sk_buff *skb;
u64 cur_time;
unsigned int next_len;
int realtime = 0;
if (sch->q.qlen == 0)
return NULL;
if ((skb = __skb_dequeue(&q->requeue)))
goto out;
PSCHED_GET_TIME(cur_time);
/*
* if there are eligible classes, use real-time criteria.
* find the class with the minimum deadline among
* the eligible classes.
*/
if ((cl = eltree_get_mindl(q, cur_time)) != NULL) {
realtime = 1;
} else {
/*
* use link-sharing criteria
* get the class with the minimum vt in the hierarchy
*/
cl = vttree_get_minvt(&q->root, cur_time);
if (cl == NULL) {
sch->qstats.overlimits++;
hfsc_schedule_watchdog(sch, cur_time);
return NULL;
}
}
skb = cl->qdisc->dequeue(cl->qdisc);
if (skb == NULL) {
if (net_ratelimit())
printk("HFSC: Non-work-conserving qdisc ?\n");
return NULL;
}
update_vf(cl, skb->len, cur_time);
if (realtime)
cl->cl_cumul += skb->len;
if (cl->qdisc->q.qlen != 0) {
if (cl->cl_flags & HFSC_RSC) {
/* update ed */
next_len = qdisc_peek_len(cl->qdisc);
if (realtime)
update_ed(cl, next_len);
else
update_d(cl, next_len);
}
} else {
/* the class becomes passive */
set_passive(cl);
}
out:
sch->flags &= ~TCQ_F_THROTTLED;
sch->q.qlen--;
return skb;
}
static int
hfsc_requeue(struct sk_buff *skb, struct Qdisc *sch)
{
struct hfsc_sched *q = qdisc_priv(sch);
__skb_queue_head(&q->requeue, skb);
sch->q.qlen++;
sch->qstats.requeues++;
return NET_XMIT_SUCCESS;
}
static unsigned int
hfsc_drop(struct Qdisc *sch)
{
struct hfsc_sched *q = qdisc_priv(sch);
struct hfsc_class *cl;
unsigned int len;
list_for_each_entry(cl, &q->droplist, dlist) {
if (cl->qdisc->ops->drop != NULL &&
(len = cl->qdisc->ops->drop(cl->qdisc)) > 0) {
if (cl->qdisc->q.qlen == 0) {
update_vf(cl, 0, 0);
set_passive(cl);
} else {
list_move_tail(&cl->dlist, &q->droplist);
}
cl->qstats.drops++;
sch->qstats.drops++;
sch->q.qlen--;
return len;
}
}
return 0;
}
static struct Qdisc_class_ops hfsc_class_ops = {
.change = hfsc_change_class,
.delete = hfsc_delete_class,
.graft = hfsc_graft_class,
.leaf = hfsc_class_leaf,
.qlen_notify = hfsc_qlen_notify,
.get = hfsc_get_class,
.put = hfsc_put_class,
.bind_tcf = hfsc_bind_tcf,
.unbind_tcf = hfsc_unbind_tcf,
.tcf_chain = hfsc_tcf_chain,
.dump = hfsc_dump_class,
.dump_stats = hfsc_dump_class_stats,
.walk = hfsc_walk
};
static struct Qdisc_ops hfsc_qdisc_ops = {
.id = "hfsc",
.init = hfsc_init_qdisc,
.change = hfsc_change_qdisc,
.reset = hfsc_reset_qdisc,
.destroy = hfsc_destroy_qdisc,
.dump = hfsc_dump_qdisc,
.enqueue = hfsc_enqueue,
.dequeue = hfsc_dequeue,
.requeue = hfsc_requeue,
.drop = hfsc_drop,
.cl_ops = &hfsc_class_ops,
.priv_size = sizeof(struct hfsc_sched),
.owner = THIS_MODULE
};
static int __init
hfsc_init(void)
{
return register_qdisc(&hfsc_qdisc_ops);
}
static void __exit
hfsc_cleanup(void)
{
unregister_qdisc(&hfsc_qdisc_ops);
}
MODULE_LICENSE("GPL");
module_init(hfsc_init);
module_exit(hfsc_cleanup);