freebsd-skq/sys/netpfil/ipfw/dn_sched_fq_pie.c
Don Lewis fe4b5f6659 Cast some expressions that multiply a long long constant by a
floating point constant to int64_t.  This avoids the runtime
conversion of the the other operand in a set of comparisons from
int64_t to floating point and doing the comparisions in floating
point.

Suggested by:	lidl
Submitted by:	Rasool Al-Saadi <ralsaadi@swin.edu.au>
MFC after:	2 weeks (with r300779)
2016-05-29 07:23:56 +00:00

1263 lines
33 KiB
C

/*
* FQ_PIE - The FlowQueue-PIE scheduler/AQM
*
* $FreeBSD$
*
* Copyright (C) 2016 Centre for Advanced Internet Architectures,
* Swinburne University of Technology, Melbourne, Australia.
* Portions of this code were made possible in part by a gift from
* The Comcast Innovation Fund.
* Implemented by Rasool Al-Saadi <ralsaadi@swin.edu.au>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' 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 THE AUTHOR OR CONTRIBUTORS 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.
*/
/* Important note:
* As there is no an office document for FQ-PIE specification, we used
* FQ-CoDel algorithm with some modifications to implement FQ-PIE.
* This FQ-PIE implementation is a beta version and have not been tested
* extensively. Our FQ-PIE uses stand-alone PIE AQM per sub-queue. By
* default, timestamp is used to calculate queue delay instead of departure
* rate estimation method. Although departure rate estimation is available
* as testing option, the results could be incorrect. Moreover, turning PIE on
* and off option is available but it does not work properly in this version.
*/
#ifdef _KERNEL
#include <sys/malloc.h>
#include <sys/socket.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/lock.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <net/if.h> /* IFNAMSIZ */
#include <netinet/in.h>
#include <netinet/ip_var.h> /* ipfw_rule_ref */
#include <netinet/ip_fw.h> /* flow_id */
#include <netinet/ip_dummynet.h>
#include <sys/proc.h>
#include <sys/rwlock.h>
#include <netpfil/ipfw/ip_fw_private.h>
#include <sys/sysctl.h>
#include <netinet/ip.h>
#include <netinet/ip6.h>
#include <netinet/ip_icmp.h>
#include <netinet/tcp.h>
#include <netinet/udp.h>
#include <sys/queue.h>
#include <sys/hash.h>
#include <netpfil/ipfw/dn_heap.h>
#include <netpfil/ipfw/ip_dn_private.h>
#include <netpfil/ipfw/dn_aqm.h>
#include <netpfil/ipfw/dn_aqm_pie.h>
#include <netpfil/ipfw/dn_sched.h>
#else
#include <dn_test.h>
#endif
#define DN_SCHED_FQ_PIE 7
/* list of queues */
STAILQ_HEAD(fq_pie_list, fq_pie_flow) ;
/* FQ_PIE parameters including PIE */
struct dn_sch_fq_pie_parms {
struct dn_aqm_pie_parms pcfg; /* PIE configuration Parameters */
/* FQ_PIE Parameters */
uint32_t flows_cnt; /* number of flows */
uint32_t limit; /* hard limit of FQ_PIE queue size*/
uint32_t quantum;
};
/* flow (sub-queue) stats */
struct flow_stats {
uint64_t tot_pkts; /* statistics counters */
uint64_t tot_bytes;
uint32_t length; /* Queue length, in packets */
uint32_t len_bytes; /* Queue length, in bytes */
uint32_t drops;
};
/* A flow of packets (sub-queue)*/
struct fq_pie_flow {
struct mq mq; /* list of packets */
struct flow_stats stats; /* statistics */
int deficit;
int active; /* 1: flow is active (in a list) */
struct pie_status pst; /* pie status variables */
struct fq_pie_si *psi; /* parent scheduler instance */
STAILQ_ENTRY(fq_pie_flow) flowchain;
};
/* extra fq_pie scheduler configurations */
struct fq_pie_schk {
struct dn_sch_fq_pie_parms cfg;
};
/* fq_pie scheduler instance */
struct fq_pie_si {
struct dn_sch_inst _si; /* standard scheduler instance */
struct dn_queue main_q; /* main queue is after si directly */
uint32_t nr_active_q;
struct fq_pie_flow *flows; /* array of flows (queues) */
uint32_t perturbation; /* random value */
struct fq_pie_list newflows; /* list of new queues */
struct fq_pie_list oldflows; /* list of old queues */
};
struct mem_to_free {
void *mem_flows;
void *mem_callout;
};
static struct mtx freemem_mtx;
static struct dn_alg fq_pie_desc;
/* Default FQ-PIE parameters including PIE */
/* PIE defaults
* target=15ms, max_burst=150ms, max_ecnth=0.1,
* alpha=0.125, beta=1.25, tupdate=15ms
* FQ-
* flows=1024, limit=10240, quantum =1514
*/
struct dn_sch_fq_pie_parms
fq_pie_sysctl = {{15000 * AQM_TIME_1US, 15000 * AQM_TIME_1US,
150000 * AQM_TIME_1US, PIE_SCALE * 0.1, PIE_SCALE * 0.125,
PIE_SCALE * 1.25, PIE_CAPDROP_ENABLED | PIE_DERAND_ENABLED},
1024, 10240, 1514};
static int
fqpie_sysctl_alpha_beta_handler(SYSCTL_HANDLER_ARGS)
{
int error;
long value;
if (!strcmp(oidp->oid_name,"alpha"))
value = fq_pie_sysctl.pcfg.alpha;
else
value = fq_pie_sysctl.pcfg.beta;
value = value * 1000 / PIE_SCALE;
error = sysctl_handle_long(oidp, &value, 0, req);
if (error != 0 || req->newptr == NULL)
return (error);
if (value < 1 || value > 7 * PIE_SCALE)
return (EINVAL);
value = (value * PIE_SCALE) / 1000;
if (!strcmp(oidp->oid_name,"alpha"))
fq_pie_sysctl.pcfg.alpha = value;
else
fq_pie_sysctl.pcfg.beta = value;
return (0);
}
static int
fqpie_sysctl_target_tupdate_maxb_handler(SYSCTL_HANDLER_ARGS)
{
int error;
long value;
if (!strcmp(oidp->oid_name,"target"))
value = fq_pie_sysctl.pcfg.qdelay_ref;
else if (!strcmp(oidp->oid_name,"tupdate"))
value = fq_pie_sysctl.pcfg.tupdate;
else
value = fq_pie_sysctl.pcfg.max_burst;
value = value / AQM_TIME_1US;
error = sysctl_handle_long(oidp, &value, 0, req);
if (error != 0 || req->newptr == NULL)
return (error);
if (value < 1 || value > 10 * AQM_TIME_1S)
return (EINVAL);
value = value * AQM_TIME_1US;
if (!strcmp(oidp->oid_name,"target"))
fq_pie_sysctl.pcfg.qdelay_ref = value;
else if (!strcmp(oidp->oid_name,"tupdate"))
fq_pie_sysctl.pcfg.tupdate = value;
else
fq_pie_sysctl.pcfg.max_burst = value;
return (0);
}
static int
fqpie_sysctl_max_ecnth_handler(SYSCTL_HANDLER_ARGS)
{
int error;
long value;
value = fq_pie_sysctl.pcfg.max_ecnth;
value = value * 1000 / PIE_SCALE;
error = sysctl_handle_long(oidp, &value, 0, req);
if (error != 0 || req->newptr == NULL)
return (error);
if (value < 1 || value > PIE_SCALE)
return (EINVAL);
value = (value * PIE_SCALE) / 1000;
fq_pie_sysctl.pcfg.max_ecnth = value;
return (0);
}
/* define FQ- PIE sysctl variables */
SYSBEGIN(f4)
SYSCTL_DECL(_net_inet);
SYSCTL_DECL(_net_inet_ip);
SYSCTL_DECL(_net_inet_ip_dummynet);
static SYSCTL_NODE(_net_inet_ip_dummynet, OID_AUTO, fqpie,
CTLFLAG_RW, 0, "FQ_PIE");
#ifdef SYSCTL_NODE
SYSCTL_PROC(_net_inet_ip_dummynet_fqpie, OID_AUTO, target,
CTLTYPE_LONG | CTLFLAG_RW, NULL, 0,
fqpie_sysctl_target_tupdate_maxb_handler, "L",
"queue target in microsecond");
SYSCTL_PROC(_net_inet_ip_dummynet_fqpie, OID_AUTO, tupdate,
CTLTYPE_LONG | CTLFLAG_RW, NULL, 0,
fqpie_sysctl_target_tupdate_maxb_handler, "L",
"the frequency of drop probability calculation in microsecond");
SYSCTL_PROC(_net_inet_ip_dummynet_fqpie, OID_AUTO, max_burst,
CTLTYPE_LONG | CTLFLAG_RW, NULL, 0,
fqpie_sysctl_target_tupdate_maxb_handler, "L",
"Burst allowance interval in microsecond");
SYSCTL_PROC(_net_inet_ip_dummynet_fqpie, OID_AUTO, max_ecnth,
CTLTYPE_LONG | CTLFLAG_RW, NULL, 0,
fqpie_sysctl_max_ecnth_handler, "L",
"ECN safeguard threshold scaled by 1000");
SYSCTL_PROC(_net_inet_ip_dummynet_fqpie, OID_AUTO, alpha,
CTLTYPE_LONG | CTLFLAG_RW, NULL, 0,
fqpie_sysctl_alpha_beta_handler, "L", "PIE alpha scaled by 1000");
SYSCTL_PROC(_net_inet_ip_dummynet_fqpie, OID_AUTO, beta,
CTLTYPE_LONG | CTLFLAG_RW, NULL, 0,
fqpie_sysctl_alpha_beta_handler, "L", "beta scaled by 1000");
SYSCTL_UINT(_net_inet_ip_dummynet_fqpie, OID_AUTO, quantum,
CTLFLAG_RW, &fq_pie_sysctl.quantum, 1514, "quantum for FQ_PIE");
SYSCTL_UINT(_net_inet_ip_dummynet_fqpie, OID_AUTO, flows,
CTLFLAG_RW, &fq_pie_sysctl.flows_cnt, 1024, "Number of queues for FQ_PIE");
SYSCTL_UINT(_net_inet_ip_dummynet_fqpie, OID_AUTO, limit,
CTLFLAG_RW, &fq_pie_sysctl.limit, 10240, "limit for FQ_PIE");
#endif
/* Helper function to update queue&main-queue and scheduler statistics.
* negative len & drop -> drop
* negative len -> dequeue
* positive len -> enqueue
* positive len + drop -> drop during enqueue
*/
__inline static void
fq_update_stats(struct fq_pie_flow *q, struct fq_pie_si *si, int len,
int drop)
{
int inc = 0;
if (len < 0)
inc = -1;
else if (len > 0)
inc = 1;
if (drop) {
si->main_q.ni.drops ++;
q->stats.drops ++;
si->_si.ni.drops ++;
io_pkt_drop ++;
}
if (!drop || (drop && len < 0)) {
/* Update stats for the main queue */
si->main_q.ni.length += inc;
si->main_q.ni.len_bytes += len;
/*update sub-queue stats */
q->stats.length += inc;
q->stats.len_bytes += len;
/*update scheduler instance stats */
si->_si.ni.length += inc;
si->_si.ni.len_bytes += len;
}
if (inc > 0) {
si->main_q.ni.tot_bytes += len;
si->main_q.ni.tot_pkts ++;
q->stats.tot_bytes +=len;
q->stats.tot_pkts++;
si->_si.ni.tot_bytes +=len;
si->_si.ni.tot_pkts ++;
}
}
/*
* Extract a packet from the head of sub-queue 'q'
* Return a packet or NULL if the queue is empty.
* If getts is set, also extract packet's timestamp from mtag.
*/
__inline static struct mbuf *
fq_pie_extract_head(struct fq_pie_flow *q, aqm_time_t *pkt_ts,
struct fq_pie_si *si, int getts)
{
struct mbuf *m = q->mq.head;
if (m == NULL)
return m;
q->mq.head = m->m_nextpkt;
fq_update_stats(q, si, -m->m_pkthdr.len, 0);
if (si->main_q.ni.length == 0) /* queue is now idle */
si->main_q.q_time = dn_cfg.curr_time;
if (getts) {
/* extract packet timestamp*/
struct m_tag *mtag;
mtag = m_tag_locate(m, MTAG_ABI_COMPAT, DN_AQM_MTAG_TS, NULL);
if (mtag == NULL){
D("PIE timestamp mtag not found!");
*pkt_ts = 0;
} else {
*pkt_ts = *(aqm_time_t *)(mtag + 1);
m_tag_delete(m,mtag);
}
}
return m;
}
/*
* Callout function for drop probability calculation
* This function is called over tupdate ms and takes pointer of FQ-PIE
* flow as an argument
*/
static void
fq_calculate_drop_prob(void *x)
{
struct fq_pie_flow *q = (struct fq_pie_flow *) x;
struct pie_status *pst = &q->pst;
struct dn_aqm_pie_parms *pprms;
int64_t p, prob, oldprob;
aqm_time_t now;
/* dealing with race condition */
if (callout_pending(&pst->aqm_pie_callout)) {
/* callout was reset */
mtx_unlock(&pst->lock_mtx);
return;
}
if (!callout_active(&pst->aqm_pie_callout)) {
/* callout was stopped */
mtx_unlock(&pst->lock_mtx);
mtx_destroy(&pst->lock_mtx);
q->psi->nr_active_q--;
return;
}
callout_deactivate(&pst->aqm_pie_callout);
now = AQM_UNOW;
pprms = pst->parms;
prob = pst->drop_prob;
/* calculate current qdelay */
if (pprms->flags & PIE_DEPRATEEST_ENABLED) {
pst->current_qdelay = ((uint64_t)q->stats.len_bytes * pst->avg_dq_time)
>> PIE_DQ_THRESHOLD_BITS;
}
/* calculate drop probability */
p = (int64_t)pprms->alpha *
((int64_t)pst->current_qdelay - (int64_t)pprms->qdelay_ref);
p +=(int64_t) pprms->beta *
((int64_t)pst->current_qdelay - (int64_t)pst->qdelay_old);
/* We PIE_MAX_PROB shift by 12-bits to increase the division precision */
p *= (PIE_MAX_PROB << 12) / AQM_TIME_1S;
/* auto-tune drop probability */
if (prob < (int64_t)(PIE_MAX_PROB * 0.000001))
p >>= 11 + PIE_FIX_POINT_BITS+12;
else if (prob < (int64_t)(PIE_MAX_PROB * 0.00001))
p >>= 9 + PIE_FIX_POINT_BITS+12;
else if (prob < (int64_t)(PIE_MAX_PROB * 0.0001))
p >>= 7 + PIE_FIX_POINT_BITS+12;
else if (prob < (int64_t)(PIE_MAX_PROB * 0.001))
p >>= 5 + PIE_FIX_POINT_BITS+12;
else if (prob < (int64_t)(PIE_MAX_PROB * 0.01))
p >>= 3 + PIE_FIX_POINT_BITS+12;
else if (prob < (int64_t)(PIE_MAX_PROB * 0.1))
p >>= 1 + PIE_FIX_POINT_BITS+12;
else
p >>= PIE_FIX_POINT_BITS+12;
oldprob = prob;
/* Cap Drop adjustment */
if ((pprms->flags & PIE_CAPDROP_ENABLED) && prob >= PIE_MAX_PROB / 10
&& p > PIE_MAX_PROB / 50 )
p = PIE_MAX_PROB / 50;
prob = prob + p;
/* decay the drop probability exponentially */
if (pst->current_qdelay == 0 && pst->qdelay_old == 0)
/* 0.98 ~= 1- 1/64 */
prob = prob - (prob >> 6);
/* check for multiplication over/under flow */
if (p>0) {
if (prob<oldprob) {
D("overflow");
prob= PIE_MAX_PROB;
}
}
else
if (prob>oldprob) {
prob= 0;
D("underflow");
}
/* make drop probability between 0 and PIE_MAX_PROB*/
if (prob < 0)
prob = 0;
else if (prob > PIE_MAX_PROB)
prob = PIE_MAX_PROB;
pst->drop_prob = prob;
/* store current delay value */
pst->qdelay_old = pst->current_qdelay;
/* update burst allowance */
if ((pst->sflags & PIE_ACTIVE) && pst->burst_allowance) {
if (pst->burst_allowance > pprms->tupdate)
pst->burst_allowance -= pprms->tupdate;
else
pst->burst_allowance = 0;
}
if (pst->sflags & PIE_ACTIVE)
callout_reset_sbt(&pst->aqm_pie_callout,
(uint64_t)pprms->tupdate * SBT_1US,
0, fq_calculate_drop_prob, q, 0);
mtx_unlock(&pst->lock_mtx);
}
/*
* Reset PIE variables & activate the queue
*/
__inline static void
fq_activate_pie(struct fq_pie_flow *q)
{
struct pie_status *pst = &q->pst;
struct dn_aqm_pie_parms *pprms;
mtx_lock(&pst->lock_mtx);
pprms = pst->parms;
pprms = pst->parms;
pst->drop_prob = 0;
pst->qdelay_old = 0;
pst->burst_allowance = pprms->max_burst;
pst->accu_prob = 0;
pst->dq_count = 0;
pst->avg_dq_time = 0;
pst->sflags = PIE_INMEASUREMENT | PIE_ACTIVE;
pst->measurement_start = AQM_UNOW;
callout_reset_sbt(&pst->aqm_pie_callout,
(uint64_t)pprms->tupdate * SBT_1US,
0, fq_calculate_drop_prob, q, 0);
mtx_unlock(&pst->lock_mtx);
}
/*
* Deactivate PIE and stop probe update callout
*/
__inline static void
fq_deactivate_pie(struct pie_status *pst)
{
mtx_lock(&pst->lock_mtx);
pst->sflags &= ~(PIE_ACTIVE | PIE_INMEASUREMENT);
callout_stop(&pst->aqm_pie_callout);
//D("PIE Deactivated");
mtx_unlock(&pst->lock_mtx);
}
/*
* Initialize PIE for sub-queue 'q'
*/
static int
pie_init(struct fq_pie_flow *q)
{
struct pie_status *pst=&q->pst;
struct dn_aqm_pie_parms *pprms = pst->parms;
struct fq_pie_schk *fqpie_schk;
fqpie_schk = (struct fq_pie_schk *)(q->psi->_si.sched+1);
int err = 0;
if (!pprms){
D("AQM_PIE is not configured");
err = EINVAL;
} else {
q->psi->nr_active_q++;
/* For speed optimization, we caculate 1/3 queue size once here */
// XXX limit divided by number of queues divided by 3 ???
pst->one_third_q_size = (fqpie_schk->cfg.limit /
fqpie_schk->cfg.flows_cnt) / 3;
mtx_init(&pst->lock_mtx, "mtx_pie", NULL, MTX_DEF);
callout_init_mtx(&pst->aqm_pie_callout, &pst->lock_mtx,
CALLOUT_RETURNUNLOCKED);
}
return err;
}
/*
* Clean up PIE status for sub-queue 'q'
* Stop callout timer and destroy mtx
*/
static int
pie_cleanup(struct fq_pie_flow *q)
{
struct pie_status *pst = &q->pst;
mtx_lock(&pst->lock_mtx);
if (callout_stop(&pst->aqm_pie_callout) || !(pst->sflags & PIE_ACTIVE)) {
mtx_unlock(&pst->lock_mtx);
mtx_destroy(&pst->lock_mtx);
q->psi->nr_active_q--;
} else {
mtx_unlock(&pst->lock_mtx);
return EBUSY;
}
return 0;
}
/*
* Dequeue and return a pcaket from sub-queue 'q' or NULL if 'q' is empty.
* Also, caculate depature time or queue delay using timestamp
*/
static struct mbuf *
pie_dequeue(struct fq_pie_flow *q, struct fq_pie_si *si)
{
struct mbuf *m;
struct dn_aqm_pie_parms *pprms;
struct pie_status *pst;
aqm_time_t now;
aqm_time_t pkt_ts, dq_time;
int32_t w;
pst = &q->pst;
pprms = q->pst.parms;
/*we extarct packet ts only when Departure Rate Estimation dis not used*/
m = fq_pie_extract_head(q, &pkt_ts, si,
!(pprms->flags & PIE_DEPRATEEST_ENABLED));
if (!m || !(pst->sflags & PIE_ACTIVE))
return m;
now = AQM_UNOW;
if (pprms->flags & PIE_DEPRATEEST_ENABLED) {
/* calculate average depature time */
if(pst->sflags & PIE_INMEASUREMENT) {
pst->dq_count += m->m_pkthdr.len;
if (pst->dq_count >= PIE_DQ_THRESHOLD) {
dq_time = now - pst->measurement_start;
/*
* if we don't have old avg dq_time i.e PIE is (re)initialized,
* don't use weight to calculate new avg_dq_time
*/
if(pst->avg_dq_time == 0)
pst->avg_dq_time = dq_time;
else {
/*
* weight = PIE_DQ_THRESHOLD/2^6, but we scaled
* weight by 2^8. Thus, scaled
* weight = PIE_DQ_THRESHOLD /2^8
* */
w = PIE_DQ_THRESHOLD >> 8;
pst->avg_dq_time = (dq_time* w
+ (pst->avg_dq_time * ((1L << 8) - w))) >> 8;
pst->sflags &= ~PIE_INMEASUREMENT;
}
}
}
/*
* Start new measurment cycle when the queue has
* PIE_DQ_THRESHOLD worth of bytes.
*/
if(!(pst->sflags & PIE_INMEASUREMENT) &&
q->stats.len_bytes >= PIE_DQ_THRESHOLD) {
pst->sflags |= PIE_INMEASUREMENT;
pst->measurement_start = now;
pst->dq_count = 0;
}
}
/* Optionally, use packet timestamp to estimate queue delay */
else
pst->current_qdelay = now - pkt_ts;
return m;
}
/*
* Enqueue a packet in q, subject to space and FQ-PIE queue management policy
* (whose parameters are in q->fs).
* Update stats for the queue and the scheduler.
* Return 0 on success, 1 on drop. The packet is consumed anyways.
*/
static int
pie_enqueue(struct fq_pie_flow *q, struct mbuf* m, struct fq_pie_si *si)
{
uint64_t len;
struct pie_status *pst;
struct dn_aqm_pie_parms *pprms;
int t;
len = m->m_pkthdr.len;
pst = &q->pst;
pprms = pst->parms;
t = ENQUE;
/* drop/mark the packet when PIE is active and burst time elapsed */
if (pst->sflags & PIE_ACTIVE && pst->burst_allowance == 0
&& drop_early(pst, q->stats.len_bytes) == DROP) {
/*
* if drop_prob over ECN threshold, drop the packet
* otherwise mark and enqueue it.
*/
if (pprms->flags & PIE_ECN_ENABLED && pst->drop_prob <
(pprms->max_ecnth << (PIE_PROB_BITS - PIE_FIX_POINT_BITS))
&& ecn_mark(m))
t = ENQUE;
else
t = DROP;
}
/* Turn PIE on when 1/3 of the queue is full */
if (!(pst->sflags & PIE_ACTIVE) && q->stats.len_bytes >=
pst->one_third_q_size) {
fq_activate_pie(q);
}
/* reset burst tolerance and optinally turn PIE off*/
if (pst->drop_prob == 0 && pst->current_qdelay < (pprms->qdelay_ref >> 1)
&& pst->qdelay_old < (pprms->qdelay_ref >> 1)) {
pst->burst_allowance = pprms->max_burst;
if (pprms->flags & PIE_ON_OFF_MODE_ENABLED && q->stats.len_bytes<=0)
fq_deactivate_pie(pst);
}
/* Use timestamp if Departure Rate Estimation mode is disabled */
if (t != DROP && !(pprms->flags & PIE_DEPRATEEST_ENABLED)) {
/* Add TS to mbuf as a TAG */
struct m_tag *mtag;
mtag = m_tag_locate(m, MTAG_ABI_COMPAT, DN_AQM_MTAG_TS, NULL);
if (mtag == NULL)
mtag = m_tag_alloc(MTAG_ABI_COMPAT, DN_AQM_MTAG_TS,
sizeof(aqm_time_t), M_NOWAIT);
if (mtag == NULL) {
m_freem(m);
t = DROP;
}
*(aqm_time_t *)(mtag + 1) = AQM_UNOW;
m_tag_prepend(m, mtag);
}
if (t != DROP) {
mq_append(&q->mq, m);
fq_update_stats(q, si, len, 0);
return 0;
} else {
fq_update_stats(q, si, len, 1);
pst->accu_prob = 0;
FREE_PKT(m);
return 1;
}
return 0;
}
/* Drop a packet form the head of FQ-PIE sub-queue */
static void
pie_drop_head(struct fq_pie_flow *q, struct fq_pie_si *si)
{
struct mbuf *m = q->mq.head;
if (m == NULL)
return;
q->mq.head = m->m_nextpkt;
fq_update_stats(q, si, -m->m_pkthdr.len, 1);
if (si->main_q.ni.length == 0) /* queue is now idle */
si->main_q.q_time = dn_cfg.curr_time;
/* reset accu_prob after packet drop */
q->pst.accu_prob = 0;
FREE_PKT(m);
}
/*
* Classify a packet to queue number using Jenkins hash function.
* Return: queue number
* the input of the hash are protocol no, perturbation, src IP, dst IP,
* src port, dst port,
*/
static inline int
fq_pie_classify_flow(struct mbuf *m, uint16_t fcount, struct fq_pie_si *si)
{
struct ip *ip;
struct tcphdr *th;
struct udphdr *uh;
uint8_t tuple[41];
uint16_t hash=0;
//#ifdef INET6
struct ip6_hdr *ip6;
int isip6;
isip6 = (mtod(m, struct ip *)->ip_v == 6) ? 1 : 0;
if(isip6) {
ip6 = mtod(m, struct ip6_hdr *);
*((uint8_t *) &tuple[0]) = ip6->ip6_nxt;
*((uint32_t *) &tuple[1]) = si->perturbation;
memcpy(&tuple[5], ip6->ip6_src.s6_addr, 16);
memcpy(&tuple[21], ip6->ip6_dst.s6_addr, 16);
switch (ip6->ip6_nxt) {
case IPPROTO_TCP:
th = (struct tcphdr *)(ip6 + 1);
*((uint16_t *) &tuple[37]) = th->th_dport;
*((uint16_t *) &tuple[39]) = th->th_sport;
break;
case IPPROTO_UDP:
uh = (struct udphdr *)(ip6 + 1);
*((uint16_t *) &tuple[37]) = uh->uh_dport;
*((uint16_t *) &tuple[39]) = uh->uh_sport;
break;
default:
memset(&tuple[37], 0, 4);
}
hash = jenkins_hash(tuple, 41, HASHINIT) % fcount;
return hash;
}
//#endif
/* IPv4 */
ip = mtod(m, struct ip *);
*((uint8_t *) &tuple[0]) = ip->ip_p;
*((uint32_t *) &tuple[1]) = si->perturbation;
*((uint32_t *) &tuple[5]) = ip->ip_src.s_addr;
*((uint32_t *) &tuple[9]) = ip->ip_dst.s_addr;
switch (ip->ip_p) {
case IPPROTO_TCP:
th = (struct tcphdr *)(ip + 1);
*((uint16_t *) &tuple[13]) = th->th_dport;
*((uint16_t *) &tuple[15]) = th->th_sport;
break;
case IPPROTO_UDP:
uh = (struct udphdr *)(ip + 1);
*((uint16_t *) &tuple[13]) = uh->uh_dport;
*((uint16_t *) &tuple[15]) = uh->uh_sport;
break;
default:
memset(&tuple[13], 0, 4);
}
hash = jenkins_hash(tuple, 17, HASHINIT) % fcount;
return hash;
}
/*
* Enqueue a packet into an appropriate queue according to
* FQ-CoDe; algorithm.
*/
static int
fq_pie_enqueue(struct dn_sch_inst *_si, struct dn_queue *_q,
struct mbuf *m)
{
struct fq_pie_si *si;
struct fq_pie_schk *schk;
struct dn_sch_fq_pie_parms *param;
struct dn_queue *mainq;
int idx, drop, i, maxidx;
mainq = (struct dn_queue *)(_si + 1);
si = (struct fq_pie_si *)_si;
schk = (struct fq_pie_schk *)(si->_si.sched+1);
param = &schk->cfg;
/* classify a packet to queue number*/
idx = fq_pie_classify_flow(m, param->flows_cnt, si);
/* enqueue packet into appropriate queue using PIE AQM.
* Note: 'pie_enqueue' function returns 1 only when it unable to
* add timestamp to packet (no limit check)*/
drop = pie_enqueue(&si->flows[idx], m, si);
/* pie unable to timestamp a packet */
if (drop)
return 1;
/* If the flow (sub-queue) is not active ,then add it to tail of
* new flows list, initialize and activate it.
*/
if (!si->flows[idx].active) {
STAILQ_INSERT_TAIL(&si->newflows, &si->flows[idx], flowchain);
si->flows[idx].deficit = param->quantum;
fq_activate_pie(&si->flows[idx]);
si->flows[idx].active = 1;
}
/* check the limit for all queues and remove a packet from the
* largest one
*/
if (mainq->ni.length > schk->cfg.limit) {
/* find first active flow */
for (maxidx = 0; maxidx < schk->cfg.flows_cnt; maxidx++)
if (si->flows[maxidx].active)
break;
if (maxidx < schk->cfg.flows_cnt) {
/* find the largest sub- queue */
for (i = maxidx + 1; i < schk->cfg.flows_cnt; i++)
if (si->flows[i].active && si->flows[i].stats.length >
si->flows[maxidx].stats.length)
maxidx = i;
pie_drop_head(&si->flows[maxidx], si);
drop = 1;
}
}
return drop;
}
/*
* Dequeue a packet from an appropriate queue according to
* FQ-CoDel algorithm.
*/
static struct mbuf *
fq_pie_dequeue(struct dn_sch_inst *_si)
{
struct fq_pie_si *si;
struct fq_pie_schk *schk;
struct dn_sch_fq_pie_parms *param;
struct fq_pie_flow *f;
struct mbuf *mbuf;
struct fq_pie_list *fq_pie_flowlist;
si = (struct fq_pie_si *)_si;
schk = (struct fq_pie_schk *)(si->_si.sched+1);
param = &schk->cfg;
do {
/* select a list to start with */
if (STAILQ_EMPTY(&si->newflows))
fq_pie_flowlist = &si->oldflows;
else
fq_pie_flowlist = &si->newflows;
/* Both new and old queue lists are empty, return NULL */
if (STAILQ_EMPTY(fq_pie_flowlist))
return NULL;
f = STAILQ_FIRST(fq_pie_flowlist);
while (f != NULL) {
/* if there is no flow(sub-queue) deficit, increase deficit
* by quantum, move the flow to the tail of old flows list
* and try another flow.
* Otherwise, the flow will be used for dequeue.
*/
if (f->deficit < 0) {
f->deficit += param->quantum;
STAILQ_REMOVE_HEAD(fq_pie_flowlist, flowchain);
STAILQ_INSERT_TAIL(&si->oldflows, f, flowchain);
} else
break;
f = STAILQ_FIRST(fq_pie_flowlist);
}
/* the new flows list is empty, try old flows list */
if (STAILQ_EMPTY(fq_pie_flowlist))
continue;
/* Dequeue a packet from the selected flow */
mbuf = pie_dequeue(f, si);
/* pie did not return a packet */
if (!mbuf) {
/* If the selected flow belongs to new flows list, then move
* it to the tail of old flows list. Otherwise, deactivate it and
* remove it from the old list and
*/
if (fq_pie_flowlist == &si->newflows) {
STAILQ_REMOVE_HEAD(fq_pie_flowlist, flowchain);
STAILQ_INSERT_TAIL(&si->oldflows, f, flowchain);
} else {
f->active = 0;
fq_deactivate_pie(&f->pst);
STAILQ_REMOVE_HEAD(fq_pie_flowlist, flowchain);
}
/* start again */
continue;
}
/* we have a packet to return,
* update flow deficit and return the packet*/
f->deficit -= mbuf->m_pkthdr.len;
return mbuf;
} while (1);
/* unreachable point */
return NULL;
}
/*
* Initialize fq_pie scheduler instance.
* also, allocate memory for flows array.
*/
static int
fq_pie_new_sched(struct dn_sch_inst *_si)
{
struct fq_pie_si *si;
struct dn_queue *q;
struct fq_pie_schk *schk;
int i;
si = (struct fq_pie_si *)_si;
schk = (struct fq_pie_schk *)(_si->sched+1);
if(si->flows) {
D("si already configured!");
return 0;
}
/* init the main queue */
q = &si->main_q;
set_oid(&q->ni.oid, DN_QUEUE, sizeof(*q));
q->_si = _si;
q->fs = _si->sched->fs;
/* allocate memory for flows array */
si->flows = malloc(schk->cfg.flows_cnt * sizeof(struct fq_pie_flow),
M_DUMMYNET, M_NOWAIT | M_ZERO);
if (si->flows == NULL) {
D("cannot allocate memory for fq_pie configuration parameters");
return ENOMEM ;
}
/* init perturbation for this si */
si->perturbation = random();
si->nr_active_q = 0;
/* init the old and new flows lists */
STAILQ_INIT(&si->newflows);
STAILQ_INIT(&si->oldflows);
/* init the flows (sub-queues) */
for (i = 0; i < schk->cfg.flows_cnt; i++) {
si->flows[i].pst.parms = &schk->cfg.pcfg;
si->flows[i].psi = si;
pie_init(&si->flows[i]);
}
/* init mtx lock and callout function for free memory */
if (!fq_pie_desc.ref_count) {
mtx_init(&freemem_mtx, "mtx_pie", NULL, MTX_DEF);
}
mtx_lock(&freemem_mtx);
fq_pie_desc.ref_count++;
mtx_unlock(&freemem_mtx);
return 0;
}
/*
* Free FQ-PIE flows memory callout function.
* This function is scheduled when a flow or more still active and
* the scheduer is about to be destroyed, to prevent memory leak.
*/
static void
free_flows(void *_mem)
{
struct mem_to_free *mem = _mem;
free(mem->mem_flows, M_DUMMYNET);
free(mem->mem_callout, M_DUMMYNET);
free(_mem, M_DUMMYNET);
fq_pie_desc.ref_count--;
if (!fq_pie_desc.ref_count) {
mtx_unlock(&freemem_mtx);
mtx_destroy(&freemem_mtx);
} else
mtx_unlock(&freemem_mtx);
//D("mem freed ok!");
}
/*
* Free fq_pie scheduler instance.
*/
static int
fq_pie_free_sched(struct dn_sch_inst *_si)
{
struct fq_pie_si *si;
struct fq_pie_schk *schk;
int i;
si = (struct fq_pie_si *)_si;
schk = (struct fq_pie_schk *)(_si->sched+1);
for (i = 0; i < schk->cfg.flows_cnt; i++) {
pie_cleanup(&si->flows[i]);
}
/* if there are still some queues have a callout going to start,
* we cannot free flows memory. If we do so, a panic can happen
* as prob calculate callout function uses flows memory.
*/
if (!si->nr_active_q) {
/* free the flows array */
free(si->flows , M_DUMMYNET);
si->flows = NULL;
mtx_lock(&freemem_mtx);
fq_pie_desc.ref_count--;
if (!fq_pie_desc.ref_count) {
mtx_unlock(&freemem_mtx);
mtx_destroy(&freemem_mtx);
} else
mtx_unlock(&freemem_mtx);
//D("ok!");
return 0;
} else {
/* memory leak happens here. So, we register a callout function to free
* flows memory later.
*/
D("unable to stop all fq_pie sub-queues!");
mtx_lock(&freemem_mtx);
struct callout *mem_callout;
struct mem_to_free *mem;
mem = malloc(sizeof(*mem), M_DUMMYNET,
M_NOWAIT | M_ZERO);
mem_callout = malloc(sizeof(*mem_callout), M_DUMMYNET,
M_NOWAIT | M_ZERO);
callout_init_mtx(mem_callout, &freemem_mtx,
CALLOUT_RETURNUNLOCKED);
mem->mem_flows = si->flows;
mem->mem_callout = mem_callout;
callout_reset_sbt(mem_callout,
(uint64_t)(si->flows[0].pst.parms->tupdate + 1000) * SBT_1US,
0, free_flows, mem, 0);
si->flows = NULL;
mtx_unlock(&freemem_mtx);
return EBUSY;
}
}
/*
* Configure FQ-PIE scheduler.
* the configurations for the scheduler is passed fromipfw userland.
*/
static int
fq_pie_config(struct dn_schk *_schk)
{
struct fq_pie_schk *schk;
struct dn_extra_parms *ep;
struct dn_sch_fq_pie_parms *fqp_cfg;
schk = (struct fq_pie_schk *)(_schk+1);
ep = (struct dn_extra_parms *) _schk->cfg;
/* par array contains fq_pie configuration as follow
* PIE: 0- qdelay_ref,1- tupdate, 2- max_burst
* 3- max_ecnth, 4- alpha, 5- beta, 6- flags
* FQ_PIE: 7- quantum, 8- limit, 9- flows
*/
if (ep && ep->oid.len ==sizeof(*ep) &&
ep->oid.subtype == DN_SCH_PARAMS) {
fqp_cfg = &schk->cfg;
if (ep->par[0] < 0)
fqp_cfg->pcfg.qdelay_ref = fq_pie_sysctl.pcfg.qdelay_ref;
else
fqp_cfg->pcfg.qdelay_ref = ep->par[0];
if (ep->par[1] < 0)
fqp_cfg->pcfg.tupdate = fq_pie_sysctl.pcfg.tupdate;
else
fqp_cfg->pcfg.tupdate = ep->par[1];
if (ep->par[2] < 0)
fqp_cfg->pcfg.max_burst = fq_pie_sysctl.pcfg.max_burst;
else
fqp_cfg->pcfg.max_burst = ep->par[2];
if (ep->par[3] < 0)
fqp_cfg->pcfg.max_ecnth = fq_pie_sysctl.pcfg.max_ecnth;
else
fqp_cfg->pcfg.max_ecnth = ep->par[3];
if (ep->par[4] < 0)
fqp_cfg->pcfg.alpha = fq_pie_sysctl.pcfg.alpha;
else
fqp_cfg->pcfg.alpha = ep->par[4];
if (ep->par[5] < 0)
fqp_cfg->pcfg.beta = fq_pie_sysctl.pcfg.beta;
else
fqp_cfg->pcfg.beta = ep->par[5];
if (ep->par[6] < 0)
fqp_cfg->pcfg.flags = 0;
else
fqp_cfg->pcfg.flags = ep->par[6];
/* FQ configurations */
if (ep->par[7] < 0)
fqp_cfg->quantum = fq_pie_sysctl.quantum;
else
fqp_cfg->quantum = ep->par[7];
if (ep->par[8] < 0)
fqp_cfg->limit = fq_pie_sysctl.limit;
else
fqp_cfg->limit = ep->par[8];
if (ep->par[9] < 0)
fqp_cfg->flows_cnt = fq_pie_sysctl.flows_cnt;
else
fqp_cfg->flows_cnt = ep->par[9];
/* Bound the configurations */
fqp_cfg->pcfg.qdelay_ref = BOUND_VAR(fqp_cfg->pcfg.qdelay_ref,
1, 5 * AQM_TIME_1S);
fqp_cfg->pcfg.tupdate = BOUND_VAR(fqp_cfg->pcfg.tupdate,
1, 5 * AQM_TIME_1S);
fqp_cfg->pcfg.max_burst = BOUND_VAR(fqp_cfg->pcfg.max_burst,
0, 5 * AQM_TIME_1S);
fqp_cfg->pcfg.max_ecnth = BOUND_VAR(fqp_cfg->pcfg.max_ecnth,
0, PIE_SCALE);
fqp_cfg->pcfg.alpha = BOUND_VAR(fqp_cfg->pcfg.alpha, 0, 7 * PIE_SCALE);
fqp_cfg->pcfg.beta = BOUND_VAR(fqp_cfg->pcfg.beta, 0, 7 * PIE_SCALE);
fqp_cfg->quantum = BOUND_VAR(fqp_cfg->quantum,1,9000);
fqp_cfg->limit= BOUND_VAR(fqp_cfg->limit,1,20480);
fqp_cfg->flows_cnt= BOUND_VAR(fqp_cfg->flows_cnt,1,65536);
}
else {
D("Wrong parameters for fq_pie scheduler");
return 1;
}
return 0;
}
/*
* Return FQ-PIE scheduler configurations
* the configurations for the scheduler is passed to userland.
*/
static int
fq_pie_getconfig (struct dn_schk *_schk, struct dn_extra_parms *ep) {
struct fq_pie_schk *schk = (struct fq_pie_schk *)(_schk+1);
struct dn_sch_fq_pie_parms *fqp_cfg;
fqp_cfg = &schk->cfg;
strcpy(ep->name, fq_pie_desc.name);
ep->par[0] = fqp_cfg->pcfg.qdelay_ref;
ep->par[1] = fqp_cfg->pcfg.tupdate;
ep->par[2] = fqp_cfg->pcfg.max_burst;
ep->par[3] = fqp_cfg->pcfg.max_ecnth;
ep->par[4] = fqp_cfg->pcfg.alpha;
ep->par[5] = fqp_cfg->pcfg.beta;
ep->par[6] = fqp_cfg->pcfg.flags;
ep->par[7] = fqp_cfg->quantum;
ep->par[8] = fqp_cfg->limit;
ep->par[9] = fqp_cfg->flows_cnt;
return 0;
}
/*
* FQ-PIE scheduler descriptor
* contains the type of the scheduler, the name, the size of extra
* data structures, and function pointers.
*/
static struct dn_alg fq_pie_desc = {
_SI( .type = ) DN_SCHED_FQ_PIE,
_SI( .name = ) "FQ_PIE",
_SI( .flags = ) 0,
_SI( .schk_datalen = ) sizeof(struct fq_pie_schk),
_SI( .si_datalen = ) sizeof(struct fq_pie_si) - sizeof(struct dn_sch_inst),
_SI( .q_datalen = ) 0,
_SI( .enqueue = ) fq_pie_enqueue,
_SI( .dequeue = ) fq_pie_dequeue,
_SI( .config = ) fq_pie_config, /* new sched i.e. sched X config ...*/
_SI( .destroy = ) NULL, /*sched x delete */
_SI( .new_sched = ) fq_pie_new_sched, /* new schd instance */
_SI( .free_sched = ) fq_pie_free_sched, /* delete schd instance */
_SI( .new_fsk = ) NULL,
_SI( .free_fsk = ) NULL,
_SI( .new_queue = ) NULL,
_SI( .free_queue = ) NULL,
_SI( .getconfig = ) fq_pie_getconfig,
_SI( .ref_count = ) 0
};
DECLARE_DNSCHED_MODULE(dn_fq_pie, &fq_pie_desc);