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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/sched/sch_hfsc.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'net/sched/sch_hfsc.c')
-rw-r--r--net/sched/sch_hfsc.c1822
1 files changed, 1822 insertions, 0 deletions
diff --git a/net/sched/sch_hfsc.c b/net/sched/sch_hfsc.c
new file mode 100644
index 00000000000..c26764bc410
--- /dev/null
+++ b/net/sched/sch_hfsc.c
@@ -0,0 +1,1822 @@
+/*
+ * 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/config.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) = 1000000ULL * 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 += 1000000 - 1;
+ do_div(dx, 1000000);
+ 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 * 1000000;
+ 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");
+ 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);
+ if (len > 0) {
+ update_vf(cl, 0, 0);
+ set_passive(cl);
+ sch->q.qlen -= 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;
+ }
+ cl->level = level + 1;
+ } 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 = kmalloc(sizeof(struct hfsc_class), GFP_KERNEL);
+ if (cl == NULL)
+ return -ENOBUFS;
+ memset(cl, 0, sizeof(struct hfsc_class));
+
+ 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);
+ 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);
+