1204591Sluigi/* 2204591Sluigi * Copyright (c) 2010 Fabio Checconi, Luigi Rizzo, Paolo Valente 3204591Sluigi * All rights reserved 4204591Sluigi * 5204591Sluigi * Redistribution and use in source and binary forms, with or without 6204591Sluigi * modification, are permitted provided that the following conditions 7204591Sluigi * are met: 8204591Sluigi * 1. Redistributions of source code must retain the above copyright 9204591Sluigi * notice, this list of conditions and the following disclaimer. 10204591Sluigi * 2. Redistributions in binary form must reproduce the above copyright 11204591Sluigi * notice, this list of conditions and the following disclaimer in the 12204591Sluigi * documentation and/or other materials provided with the distribution. 13204591Sluigi * 14204591Sluigi * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15204591Sluigi * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16204591Sluigi * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17204591Sluigi * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18204591Sluigi * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19204591Sluigi * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20204591Sluigi * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21204591Sluigi * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22204591Sluigi * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23204591Sluigi * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24204591Sluigi * SUCH DAMAGE. 25204591Sluigi */ 26204591Sluigi 27204591Sluigi/* 28204591Sluigi * $FreeBSD$ 29204591Sluigi */ 30204591Sluigi 31204591Sluigi#ifdef _KERNEL 32204591Sluigi#include <sys/malloc.h> 33204591Sluigi#include <sys/socket.h> 34204591Sluigi#include <sys/socketvar.h> 35204591Sluigi#include <sys/kernel.h> 36204591Sluigi#include <sys/mbuf.h> 37204591Sluigi#include <sys/module.h> 38204591Sluigi#include <net/if.h> /* IFNAMSIZ */ 39204591Sluigi#include <netinet/in.h> 40204591Sluigi#include <netinet/ip_var.h> /* ipfw_rule_ref */ 41204591Sluigi#include <netinet/ip_fw.h> /* flow_id */ 42204591Sluigi#include <netinet/ip_dummynet.h> 43240494Sglebius#include <netpfil/ipfw/dn_heap.h> 44240494Sglebius#include <netpfil/ipfw/ip_dn_private.h> 45240494Sglebius#include <netpfil/ipfw/dn_sched.h> 46204591Sluigi#else 47204591Sluigi#include <dn_test.h> 48204591Sluigi#endif 49204591Sluigi 50204591Sluigi#ifdef QFQ_DEBUG 51204591Sluigistruct qfq_sched; 52204591Sluigistatic void dump_sched(struct qfq_sched *q, const char *msg); 53204591Sluigi#define NO(x) x 54204591Sluigi#else 55204591Sluigi#define NO(x) 56204591Sluigi#endif 57204591Sluigi#define DN_SCHED_QFQ 4 // XXX Where? 58204591Sluigitypedef unsigned long bitmap; 59204591Sluigi 60204591Sluigi/* 61204591Sluigi * bitmaps ops are critical. Some linux versions have __fls 62204591Sluigi * and the bitmap ops. Some machines have ffs 63204591Sluigi */ 64213253Sluigi#if defined(_WIN32) || (defined(__MIPSEL__) && defined(LINUX_24)) 65204591Sluigiint fls(unsigned int n) 66204591Sluigi{ 67204591Sluigi int i = 0; 68204591Sluigi for (i = 0; n > 0; n >>= 1, i++) 69204591Sluigi ; 70204591Sluigi return i; 71204591Sluigi} 72204591Sluigi#endif 73204591Sluigi 74213253Sluigi#if !defined(_KERNEL) || defined( __FreeBSD__ ) || defined(_WIN32) || (defined(__MIPSEL__) && defined(LINUX_24)) 75204591Sluigistatic inline unsigned long __fls(unsigned long word) 76204591Sluigi{ 77204591Sluigi return fls(word) - 1; 78204591Sluigi} 79204591Sluigi#endif 80204591Sluigi 81204591Sluigi#if !defined(_KERNEL) || !defined(__linux__) 82204591Sluigi#ifdef QFQ_DEBUG 83204591Sluigiint test_bit(int ix, bitmap *p) 84204591Sluigi{ 85204591Sluigi if (ix < 0 || ix > 31) 86204591Sluigi D("bad index %d", ix); 87204591Sluigi return *p & (1<<ix); 88204591Sluigi} 89204591Sluigivoid __set_bit(int ix, bitmap *p) 90204591Sluigi{ 91204591Sluigi if (ix < 0 || ix > 31) 92204591Sluigi D("bad index %d", ix); 93204591Sluigi *p |= (1<<ix); 94204591Sluigi} 95204591Sluigivoid __clear_bit(int ix, bitmap *p) 96204591Sluigi{ 97204591Sluigi if (ix < 0 || ix > 31) 98204591Sluigi D("bad index %d", ix); 99204591Sluigi *p &= ~(1<<ix); 100204591Sluigi} 101204591Sluigi#else /* !QFQ_DEBUG */ 102204591Sluigi/* XXX do we have fast version, or leave it to the compiler ? */ 103204591Sluigi#define test_bit(ix, pData) ((*pData) & (1<<(ix))) 104204591Sluigi#define __set_bit(ix, pData) (*pData) |= (1<<(ix)) 105204591Sluigi#define __clear_bit(ix, pData) (*pData) &= ~(1<<(ix)) 106204591Sluigi#endif /* !QFQ_DEBUG */ 107204591Sluigi#endif /* !__linux__ */ 108204591Sluigi 109204591Sluigi#ifdef __MIPSEL__ 110213253Sluigi#define __clear_bit(ix, pData) (*pData) &= ~(1<<(ix)) 111204591Sluigi#endif 112204591Sluigi 113204591Sluigi/*-------------------------------------------*/ 114204591Sluigi/* 115204591Sluigi 116204591SluigiVirtual time computations. 117204591Sluigi 118204591SluigiS, F and V are all computed in fixed point arithmetic with 119204591SluigiFRAC_BITS decimal bits. 120204591Sluigi 121204591Sluigi QFQ_MAX_INDEX is the maximum index allowed for a group. We need 122204591Sluigi one bit per index. 123204591Sluigi QFQ_MAX_WSHIFT is the maximum power of two supported as a weight. 124204591Sluigi The layout of the bits is as below: 125204591Sluigi 126204591Sluigi [ MTU_SHIFT ][ FRAC_BITS ] 127204591Sluigi [ MAX_INDEX ][ MIN_SLOT_SHIFT ] 128204591Sluigi ^.__grp->index = 0 129204591Sluigi *.__grp->slot_shift 130204591Sluigi 131204591Sluigi where MIN_SLOT_SHIFT is derived by difference from the others. 132204591Sluigi 133204591SluigiThe max group index corresponds to Lmax/w_min, where 134204591SluigiLmax=1<<MTU_SHIFT, w_min = 1 . 135204591SluigiFrom this, and knowing how many groups (MAX_INDEX) we want, 136204591Sluigiwe can derive the shift corresponding to each group. 137204591Sluigi 138204591SluigiBecause we often need to compute 139204591Sluigi F = S + len/w_i and V = V + len/wsum 140204591Sluigiinstead of storing w_i store the value 141204591Sluigi inv_w = (1<<FRAC_BITS)/w_i 142204591Sluigiso we can do F = S + len * inv_w * wsum. 143204591SluigiWe use W_TOT in the formulas so we can easily move between 144204591Sluigistatic and adaptive weight sum. 145204591Sluigi 146204591SluigiThe per-scheduler-instance data contain all the data structures 147204591Sluigifor the scheduler: bitmaps and bucket lists. 148204591Sluigi 149204591Sluigi */ 150204591Sluigi/* 151204591Sluigi * Maximum number of consecutive slots occupied by backlogged classes 152204591Sluigi * inside a group. This is approx lmax/lmin + 5. 153204591Sluigi * XXX check because it poses constraints on MAX_INDEX 154204591Sluigi */ 155204591Sluigi#define QFQ_MAX_SLOTS 32 156204591Sluigi/* 157204591Sluigi * Shifts used for class<->group mapping. Class weights are 158204591Sluigi * in the range [1, QFQ_MAX_WEIGHT], we to map each class i to the 159204591Sluigi * group with the smallest index that can support the L_i / r_i 160204591Sluigi * configured for the class. 161204591Sluigi * 162204591Sluigi * grp->index is the index of the group; and grp->slot_shift 163204591Sluigi * is the shift for the corresponding (scaled) sigma_i. 164204591Sluigi * 165204591Sluigi * When computing the group index, we do (len<<FP_SHIFT)/weight, 166204591Sluigi * then compute an FLS (which is like a log2()), and if the result 167204591Sluigi * is below the MAX_INDEX region we use 0 (which is the same as 168204591Sluigi * using a larger len). 169204591Sluigi */ 170204591Sluigi#define QFQ_MAX_INDEX 19 171204591Sluigi#define QFQ_MAX_WSHIFT 16 /* log2(max_weight) */ 172204591Sluigi 173204591Sluigi#define QFQ_MAX_WEIGHT (1<<QFQ_MAX_WSHIFT) 174204591Sluigi#define QFQ_MAX_WSUM (2*QFQ_MAX_WEIGHT) 175204591Sluigi//#define IWSUM (q->i_wsum) 176204591Sluigi#define IWSUM ((1<<FRAC_BITS)/QFQ_MAX_WSUM) 177204591Sluigi 178204591Sluigi#define FRAC_BITS 30 /* fixed point arithmetic */ 179204591Sluigi#define ONE_FP (1UL << FRAC_BITS) 180204591Sluigi 181204591Sluigi#define QFQ_MTU_SHIFT 11 /* log2(max_len) */ 182204591Sluigi#define QFQ_MIN_SLOT_SHIFT (FRAC_BITS + QFQ_MTU_SHIFT - QFQ_MAX_INDEX) 183204591Sluigi 184204591Sluigi/* 185204591Sluigi * Possible group states, also indexes for the bitmaps array in 186204591Sluigi * struct qfq_queue. We rely on ER, IR, EB, IB being numbered 0..3 187204591Sluigi */ 188204591Sluigienum qfq_state { ER, IR, EB, IB, QFQ_MAX_STATE }; 189204591Sluigi 190204591Sluigistruct qfq_group; 191204591Sluigi/* 192204591Sluigi * additional queue info. Some of this info should come from 193204591Sluigi * the flowset, we copy them here for faster processing. 194204591Sluigi * This is an overlay of the struct dn_queue 195204591Sluigi */ 196204591Sluigistruct qfq_class { 197204591Sluigi struct dn_queue _q; 198204591Sluigi uint64_t S, F; /* flow timestamps (exact) */ 199204591Sluigi struct qfq_class *next; /* Link for the slot list. */ 200204591Sluigi 201204591Sluigi /* group we belong to. In principle we would need the index, 202204591Sluigi * which is log_2(lmax/weight), but we never reference it 203204591Sluigi * directly, only the group. 204204591Sluigi */ 205204591Sluigi struct qfq_group *grp; 206204591Sluigi 207204591Sluigi /* these are copied from the flowset. */ 208204591Sluigi uint32_t inv_w; /* ONE_FP/weight */ 209204591Sluigi uint32_t lmax; /* Max packet size for this flow. */ 210204591Sluigi}; 211204591Sluigi 212204591Sluigi/* Group descriptor, see the paper for details. 213204591Sluigi * Basically this contains the bucket lists 214204591Sluigi */ 215204591Sluigistruct qfq_group { 216204591Sluigi uint64_t S, F; /* group timestamps (approx). */ 217204591Sluigi unsigned int slot_shift; /* Slot shift. */ 218204591Sluigi unsigned int index; /* Group index. */ 219204591Sluigi unsigned int front; /* Index of the front slot. */ 220204591Sluigi bitmap full_slots; /* non-empty slots */ 221204591Sluigi 222204591Sluigi /* Array of lists of active classes. */ 223204591Sluigi struct qfq_class *slots[QFQ_MAX_SLOTS]; 224204591Sluigi}; 225204591Sluigi 226204591Sluigi/* scheduler instance descriptor. */ 227204591Sluigistruct qfq_sched { 228204591Sluigi uint64_t V; /* Precise virtual time. */ 229204591Sluigi uint32_t wsum; /* weight sum */ 230204591Sluigi NO(uint32_t i_wsum; /* ONE_FP/w_sum */ 231204591Sluigi uint32_t _queued; /* debugging */ 232204591Sluigi uint32_t loops; /* debugging */) 233204591Sluigi bitmap bitmaps[QFQ_MAX_STATE]; /* Group bitmaps. */ 234204591Sluigi struct qfq_group groups[QFQ_MAX_INDEX + 1]; /* The groups. */ 235204591Sluigi}; 236204591Sluigi 237204591Sluigi/*---- support functions ----------------------------*/ 238204591Sluigi 239204591Sluigi/* Generic comparison function, handling wraparound. */ 240204591Sluigistatic inline int qfq_gt(uint64_t a, uint64_t b) 241204591Sluigi{ 242204591Sluigi return (int64_t)(a - b) > 0; 243204591Sluigi} 244204591Sluigi 245204591Sluigi/* Round a precise timestamp to its slotted value. */ 246204591Sluigistatic inline uint64_t qfq_round_down(uint64_t ts, unsigned int shift) 247204591Sluigi{ 248204591Sluigi return ts & ~((1ULL << shift) - 1); 249204591Sluigi} 250204591Sluigi 251204591Sluigi/* return the pointer to the group with lowest index in the bitmap */ 252204591Sluigistatic inline struct qfq_group *qfq_ffs(struct qfq_sched *q, 253204591Sluigi unsigned long bitmap) 254204591Sluigi{ 255204591Sluigi int index = ffs(bitmap) - 1; // zero-based 256204591Sluigi return &q->groups[index]; 257204591Sluigi} 258204591Sluigi 259204591Sluigi/* 260204591Sluigi * Calculate a flow index, given its weight and maximum packet length. 261204591Sluigi * index = log_2(maxlen/weight) but we need to apply the scaling. 262204591Sluigi * This is used only once at flow creation. 263204591Sluigi */ 264204591Sluigistatic int qfq_calc_index(uint32_t inv_w, unsigned int maxlen) 265204591Sluigi{ 266204591Sluigi uint64_t slot_size = (uint64_t)maxlen *inv_w; 267204591Sluigi unsigned long size_map; 268204591Sluigi int index = 0; 269204591Sluigi 270204591Sluigi size_map = (unsigned long)(slot_size >> QFQ_MIN_SLOT_SHIFT); 271204591Sluigi if (!size_map) 272204591Sluigi goto out; 273204591Sluigi 274204591Sluigi index = __fls(size_map) + 1; // basically a log_2() 275204591Sluigi index -= !(slot_size - (1ULL << (index + QFQ_MIN_SLOT_SHIFT - 1))); 276204591Sluigi 277204591Sluigi if (index < 0) 278204591Sluigi index = 0; 279204591Sluigi 280204591Sluigiout: 281204591Sluigi ND("W = %d, L = %d, I = %d\n", ONE_FP/inv_w, maxlen, index); 282204591Sluigi return index; 283204591Sluigi} 284204591Sluigi/*---- end support functions ----*/ 285204591Sluigi 286204591Sluigi/*-------- API calls --------------------------------*/ 287204591Sluigi/* 288204591Sluigi * Validate and copy parameters from flowset. 289204591Sluigi */ 290204591Sluigistatic int 291204591Sluigiqfq_new_queue(struct dn_queue *_q) 292204591Sluigi{ 293204591Sluigi struct qfq_sched *q = (struct qfq_sched *)(_q->_si + 1); 294204591Sluigi struct qfq_class *cl = (struct qfq_class *)_q; 295204591Sluigi int i; 296204591Sluigi uint32_t w; /* approximated weight */ 297204591Sluigi 298204591Sluigi /* import parameters from the flowset. They should be correct 299204591Sluigi * already. 300204591Sluigi */ 301204591Sluigi w = _q->fs->fs.par[0]; 302204591Sluigi cl->lmax = _q->fs->fs.par[1]; 303204591Sluigi if (!w || w > QFQ_MAX_WEIGHT) { 304204591Sluigi w = 1; 305204591Sluigi D("rounding weight to 1"); 306204591Sluigi } 307204591Sluigi cl->inv_w = ONE_FP/w; 308204591Sluigi w = ONE_FP/cl->inv_w; 309204591Sluigi if (q->wsum + w > QFQ_MAX_WSUM) 310204591Sluigi return EINVAL; 311204591Sluigi 312204591Sluigi i = qfq_calc_index(cl->inv_w, cl->lmax); 313204591Sluigi cl->grp = &q->groups[i]; 314204591Sluigi q->wsum += w; 315204591Sluigi // XXX cl->S = q->V; ? 316204591Sluigi // XXX compute q->i_wsum 317204591Sluigi return 0; 318204591Sluigi} 319204591Sluigi 320204591Sluigi/* remove an empty queue */ 321204591Sluigistatic int 322204591Sluigiqfq_free_queue(struct dn_queue *_q) 323204591Sluigi{ 324204591Sluigi struct qfq_sched *q = (struct qfq_sched *)(_q->_si + 1); 325204591Sluigi struct qfq_class *cl = (struct qfq_class *)_q; 326204591Sluigi if (cl->inv_w) { 327204591Sluigi q->wsum -= ONE_FP/cl->inv_w; 328204591Sluigi cl->inv_w = 0; /* reset weight to avoid run twice */ 329204591Sluigi } 330204591Sluigi return 0; 331204591Sluigi} 332204591Sluigi 333204591Sluigi/* Calculate a mask to mimic what would be ffs_from(). */ 334204591Sluigistatic inline unsigned long 335204591Sluigimask_from(unsigned long bitmap, int from) 336204591Sluigi{ 337204591Sluigi return bitmap & ~((1UL << from) - 1); 338204591Sluigi} 339204591Sluigi 340204591Sluigi/* 341204591Sluigi * The state computation relies on ER=0, IR=1, EB=2, IB=3 342204591Sluigi * First compute eligibility comparing grp->S, q->V, 343204591Sluigi * then check if someone is blocking us and possibly add EB 344204591Sluigi */ 345204591Sluigistatic inline unsigned int 346204591Sluigiqfq_calc_state(struct qfq_sched *q, struct qfq_group *grp) 347204591Sluigi{ 348204591Sluigi /* if S > V we are not eligible */ 349204591Sluigi unsigned int state = qfq_gt(grp->S, q->V); 350204591Sluigi unsigned long mask = mask_from(q->bitmaps[ER], grp->index); 351204591Sluigi struct qfq_group *next; 352204591Sluigi 353204591Sluigi if (mask) { 354204591Sluigi next = qfq_ffs(q, mask); 355204591Sluigi if (qfq_gt(grp->F, next->F)) 356204591Sluigi state |= EB; 357204591Sluigi } 358204591Sluigi 359204591Sluigi return state; 360204591Sluigi} 361204591Sluigi 362204591Sluigi/* 363204591Sluigi * In principle 364204591Sluigi * q->bitmaps[dst] |= q->bitmaps[src] & mask; 365204591Sluigi * q->bitmaps[src] &= ~mask; 366204591Sluigi * but we should make sure that src != dst 367204591Sluigi */ 368204591Sluigistatic inline void 369204591Sluigiqfq_move_groups(struct qfq_sched *q, unsigned long mask, int src, int dst) 370204591Sluigi{ 371204591Sluigi q->bitmaps[dst] |= q->bitmaps[src] & mask; 372204591Sluigi q->bitmaps[src] &= ~mask; 373204591Sluigi} 374204591Sluigi 375204591Sluigistatic inline void 376204591Sluigiqfq_unblock_groups(struct qfq_sched *q, int index, uint64_t old_finish) 377204591Sluigi{ 378204591Sluigi unsigned long mask = mask_from(q->bitmaps[ER], index + 1); 379204591Sluigi struct qfq_group *next; 380204591Sluigi 381204591Sluigi if (mask) { 382204591Sluigi next = qfq_ffs(q, mask); 383204591Sluigi if (!qfq_gt(next->F, old_finish)) 384204591Sluigi return; 385204591Sluigi } 386204591Sluigi 387204591Sluigi mask = (1UL << index) - 1; 388204591Sluigi qfq_move_groups(q, mask, EB, ER); 389204591Sluigi qfq_move_groups(q, mask, IB, IR); 390204591Sluigi} 391204591Sluigi 392204591Sluigi/* 393204591Sluigi * perhaps 394204591Sluigi * 395204591Sluigi old_V ^= q->V; 396204591Sluigi old_V >>= QFQ_MIN_SLOT_SHIFT; 397204591Sluigi if (old_V) { 398204591Sluigi ... 399204591Sluigi } 400204591Sluigi * 401204591Sluigi */ 402204591Sluigistatic inline void 403204591Sluigiqfq_make_eligible(struct qfq_sched *q, uint64_t old_V) 404204591Sluigi{ 405204591Sluigi unsigned long mask, vslot, old_vslot; 406204591Sluigi 407204591Sluigi vslot = q->V >> QFQ_MIN_SLOT_SHIFT; 408204591Sluigi old_vslot = old_V >> QFQ_MIN_SLOT_SHIFT; 409204591Sluigi 410204591Sluigi if (vslot != old_vslot) { 411204591Sluigi mask = (2UL << (__fls(vslot ^ old_vslot))) - 1; 412204591Sluigi qfq_move_groups(q, mask, IR, ER); 413204591Sluigi qfq_move_groups(q, mask, IB, EB); 414204591Sluigi } 415204591Sluigi} 416204591Sluigi 417204591Sluigi/* 418204591Sluigi * XXX we should make sure that slot becomes less than 32. 419204591Sluigi * This is guaranteed by the input values. 420204591Sluigi * roundedS is always cl->S rounded on grp->slot_shift bits. 421204591Sluigi */ 422204591Sluigistatic inline void 423204591Sluigiqfq_slot_insert(struct qfq_group *grp, struct qfq_class *cl, uint64_t roundedS) 424204591Sluigi{ 425204591Sluigi uint64_t slot = (roundedS - grp->S) >> grp->slot_shift; 426204591Sluigi unsigned int i = (grp->front + slot) % QFQ_MAX_SLOTS; 427204591Sluigi 428204591Sluigi cl->next = grp->slots[i]; 429204591Sluigi grp->slots[i] = cl; 430204591Sluigi __set_bit(slot, &grp->full_slots); 431204591Sluigi} 432204591Sluigi 433204591Sluigi/* 434204591Sluigi * remove the entry from the slot 435204591Sluigi */ 436204591Sluigistatic inline void 437204591Sluigiqfq_front_slot_remove(struct qfq_group *grp) 438204591Sluigi{ 439204591Sluigi struct qfq_class **h = &grp->slots[grp->front]; 440204591Sluigi 441204591Sluigi *h = (*h)->next; 442204591Sluigi if (!*h) 443204591Sluigi __clear_bit(0, &grp->full_slots); 444204591Sluigi} 445204591Sluigi 446204591Sluigi/* 447204591Sluigi * Returns the first full queue in a group. As a side effect, 448204591Sluigi * adjust the bucket list so the first non-empty bucket is at 449204591Sluigi * position 0 in full_slots. 450204591Sluigi */ 451204591Sluigistatic inline struct qfq_class * 452204591Sluigiqfq_slot_scan(struct qfq_group *grp) 453204591Sluigi{ 454204591Sluigi int i; 455204591Sluigi 456204591Sluigi ND("grp %d full %x", grp->index, grp->full_slots); 457204591Sluigi if (!grp->full_slots) 458204591Sluigi return NULL; 459204591Sluigi 460204591Sluigi i = ffs(grp->full_slots) - 1; // zero-based 461204591Sluigi if (i > 0) { 462204591Sluigi grp->front = (grp->front + i) % QFQ_MAX_SLOTS; 463204591Sluigi grp->full_slots >>= i; 464204591Sluigi } 465204591Sluigi 466204591Sluigi return grp->slots[grp->front]; 467204591Sluigi} 468204591Sluigi 469204591Sluigi/* 470204591Sluigi * adjust the bucket list. When the start time of a group decreases, 471204591Sluigi * we move the index down (modulo QFQ_MAX_SLOTS) so we don't need to 472204591Sluigi * move the objects. The mask of occupied slots must be shifted 473204591Sluigi * because we use ffs() to find the first non-empty slot. 474204591Sluigi * This covers decreases in the group's start time, but what about 475204591Sluigi * increases of the start time ? 476204591Sluigi * Here too we should make sure that i is less than 32 477204591Sluigi */ 478204591Sluigistatic inline void 479204591Sluigiqfq_slot_rotate(struct qfq_sched *q, struct qfq_group *grp, uint64_t roundedS) 480204591Sluigi{ 481204591Sluigi unsigned int i = (grp->S - roundedS) >> grp->slot_shift; 482204591Sluigi 483204591Sluigi grp->full_slots <<= i; 484204591Sluigi grp->front = (grp->front - i) % QFQ_MAX_SLOTS; 485204591Sluigi} 486204591Sluigi 487204591Sluigi 488204591Sluigistatic inline void 489204591Sluigiqfq_update_eligible(struct qfq_sched *q, uint64_t old_V) 490204591Sluigi{ 491204591Sluigi bitmap ineligible; 492204591Sluigi 493204591Sluigi ineligible = q->bitmaps[IR] | q->bitmaps[IB]; 494204591Sluigi if (ineligible) { 495204591Sluigi if (!q->bitmaps[ER]) { 496204591Sluigi struct qfq_group *grp; 497204591Sluigi grp = qfq_ffs(q, ineligible); 498204591Sluigi if (qfq_gt(grp->S, q->V)) 499204591Sluigi q->V = grp->S; 500204591Sluigi } 501204591Sluigi qfq_make_eligible(q, old_V); 502204591Sluigi } 503204591Sluigi} 504204591Sluigi 505204591Sluigi/* 506204591Sluigi * Updates the class, returns true if also the group needs to be updated. 507204591Sluigi */ 508204591Sluigistatic inline int 509204591Sluigiqfq_update_class(struct qfq_sched *q, struct qfq_group *grp, 510204591Sluigi struct qfq_class *cl) 511204591Sluigi{ 512204591Sluigi 513204591Sluigi cl->S = cl->F; 514204591Sluigi if (cl->_q.mq.head == NULL) { 515204591Sluigi qfq_front_slot_remove(grp); 516204591Sluigi } else { 517204591Sluigi unsigned int len; 518204591Sluigi uint64_t roundedS; 519204591Sluigi 520204591Sluigi len = cl->_q.mq.head->m_pkthdr.len; 521204591Sluigi cl->F = cl->S + (uint64_t)len * cl->inv_w; 522204591Sluigi roundedS = qfq_round_down(cl->S, grp->slot_shift); 523204591Sluigi if (roundedS == grp->S) 524204591Sluigi return 0; 525204591Sluigi 526204591Sluigi qfq_front_slot_remove(grp); 527204591Sluigi qfq_slot_insert(grp, cl, roundedS); 528204591Sluigi } 529204591Sluigi return 1; 530204591Sluigi} 531204591Sluigi 532204591Sluigistatic struct mbuf * 533204591Sluigiqfq_dequeue(struct dn_sch_inst *si) 534204591Sluigi{ 535204591Sluigi struct qfq_sched *q = (struct qfq_sched *)(si + 1); 536204591Sluigi struct qfq_group *grp; 537204591Sluigi struct qfq_class *cl; 538204591Sluigi struct mbuf *m; 539204591Sluigi uint64_t old_V; 540204591Sluigi 541204591Sluigi NO(q->loops++;) 542204591Sluigi if (!q->bitmaps[ER]) { 543204591Sluigi NO(if (q->queued) 544204591Sluigi dump_sched(q, "start dequeue");) 545204591Sluigi return NULL; 546204591Sluigi } 547204591Sluigi 548204591Sluigi grp = qfq_ffs(q, q->bitmaps[ER]); 549204591Sluigi 550204591Sluigi cl = grp->slots[grp->front]; 551204591Sluigi /* extract from the first bucket in the bucket list */ 552204591Sluigi m = dn_dequeue(&cl->_q); 553204591Sluigi 554204591Sluigi if (!m) { 555204591Sluigi D("BUG/* non-workconserving leaf */"); 556204591Sluigi return NULL; 557204591Sluigi } 558204591Sluigi NO(q->queued--;) 559204591Sluigi old_V = q->V; 560204591Sluigi q->V += (uint64_t)m->m_pkthdr.len * IWSUM; 561204591Sluigi ND("m is %p F 0x%llx V now 0x%llx", m, cl->F, q->V); 562204591Sluigi 563204591Sluigi if (qfq_update_class(q, grp, cl)) { 564204591Sluigi uint64_t old_F = grp->F; 565204591Sluigi cl = qfq_slot_scan(grp); 566204591Sluigi if (!cl) { /* group gone, remove from ER */ 567204591Sluigi __clear_bit(grp->index, &q->bitmaps[ER]); 568204591Sluigi // grp->S = grp->F + 1; // XXX debugging only 569204591Sluigi } else { 570204591Sluigi uint64_t roundedS = qfq_round_down(cl->S, grp->slot_shift); 571204591Sluigi unsigned int s; 572204591Sluigi 573204591Sluigi if (grp->S == roundedS) 574204591Sluigi goto skip_unblock; 575204591Sluigi grp->S = roundedS; 576204591Sluigi grp->F = roundedS + (2ULL << grp->slot_shift); 577204591Sluigi /* remove from ER and put in the new set */ 578204591Sluigi __clear_bit(grp->index, &q->bitmaps[ER]); 579204591Sluigi s = qfq_calc_state(q, grp); 580204591Sluigi __set_bit(grp->index, &q->bitmaps[s]); 581204591Sluigi } 582204591Sluigi /* we need to unblock even if the group has gone away */ 583204591Sluigi qfq_unblock_groups(q, grp->index, old_F); 584204591Sluigi } 585204591Sluigi 586204591Sluigiskip_unblock: 587204591Sluigi qfq_update_eligible(q, old_V); 588204591Sluigi NO(if (!q->bitmaps[ER] && q->queued) 589204591Sluigi dump_sched(q, "end dequeue");) 590204591Sluigi 591204591Sluigi return m; 592204591Sluigi} 593204591Sluigi 594204591Sluigi/* 595204591Sluigi * Assign a reasonable start time for a new flow k in group i. 596204591Sluigi * Admissible values for \hat(F) are multiples of \sigma_i 597204591Sluigi * no greater than V+\sigma_i . Larger values mean that 598204591Sluigi * we had a wraparound so we consider the timestamp to be stale. 599204591Sluigi * 600204591Sluigi * If F is not stale and F >= V then we set S = F. 601204591Sluigi * Otherwise we should assign S = V, but this may violate 602204591Sluigi * the ordering in ER. So, if we have groups in ER, set S to 603204591Sluigi * the F_j of the first group j which would be blocking us. 604204591Sluigi * We are guaranteed not to move S backward because 605204591Sluigi * otherwise our group i would still be blocked. 606204591Sluigi */ 607204591Sluigistatic inline void 608204591Sluigiqfq_update_start(struct qfq_sched *q, struct qfq_class *cl) 609204591Sluigi{ 610204591Sluigi unsigned long mask; 611230614Sluigi uint64_t limit, roundedF; 612204591Sluigi int slot_shift = cl->grp->slot_shift; 613204591Sluigi 614204591Sluigi roundedF = qfq_round_down(cl->F, slot_shift); 615204591Sluigi limit = qfq_round_down(q->V, slot_shift) + (1UL << slot_shift); 616204591Sluigi 617204591Sluigi if (!qfq_gt(cl->F, q->V) || qfq_gt(roundedF, limit)) { 618204591Sluigi /* timestamp was stale */ 619204591Sluigi mask = mask_from(q->bitmaps[ER], cl->grp->index); 620204591Sluigi if (mask) { 621204591Sluigi struct qfq_group *next = qfq_ffs(q, mask); 622204591Sluigi if (qfq_gt(roundedF, next->F)) { 623204591Sluigi cl->S = next->F; 624204591Sluigi return; 625204591Sluigi } 626204591Sluigi } 627204591Sluigi cl->S = q->V; 628204591Sluigi } else { /* timestamp is not stale */ 629204591Sluigi cl->S = cl->F; 630204591Sluigi } 631204591Sluigi} 632204591Sluigi 633204591Sluigistatic int 634204591Sluigiqfq_enqueue(struct dn_sch_inst *si, struct dn_queue *_q, struct mbuf *m) 635204591Sluigi{ 636204591Sluigi struct qfq_sched *q = (struct qfq_sched *)(si + 1); 637204591Sluigi struct qfq_group *grp; 638204591Sluigi struct qfq_class *cl = (struct qfq_class *)_q; 639204591Sluigi uint64_t roundedS; 640204591Sluigi int s; 641204591Sluigi 642204591Sluigi NO(q->loops++;) 643204591Sluigi DX(4, "len %d flow %p inv_w 0x%x grp %d", m->m_pkthdr.len, 644204591Sluigi _q, cl->inv_w, cl->grp->index); 645204591Sluigi /* XXX verify that the packet obeys the parameters */ 646204591Sluigi if (m != _q->mq.head) { 647204591Sluigi if (dn_enqueue(_q, m, 0)) /* packet was dropped */ 648204591Sluigi return 1; 649204591Sluigi NO(q->queued++;) 650204591Sluigi if (m != _q->mq.head) 651204591Sluigi return 0; 652204591Sluigi } 653204591Sluigi /* If reach this point, queue q was idle */ 654204591Sluigi grp = cl->grp; 655204591Sluigi qfq_update_start(q, cl); /* adjust start time */ 656204591Sluigi /* compute new finish time and rounded start. */ 657204591Sluigi cl->F = cl->S + (uint64_t)(m->m_pkthdr.len) * cl->inv_w; 658204591Sluigi roundedS = qfq_round_down(cl->S, grp->slot_shift); 659204591Sluigi 660204591Sluigi /* 661204591Sluigi * insert cl in the correct bucket. 662204591Sluigi * If cl->S >= grp->S we don't need to adjust the 663204591Sluigi * bucket list and simply go to the insertion phase. 664204591Sluigi * Otherwise grp->S is decreasing, we must make room 665204591Sluigi * in the bucket list, and also recompute the group state. 666204591Sluigi * Finally, if there were no flows in this group and nobody 667204591Sluigi * was in ER make sure to adjust V. 668204591Sluigi */ 669204591Sluigi if (grp->full_slots) { 670204591Sluigi if (!qfq_gt(grp->S, cl->S)) 671204591Sluigi goto skip_update; 672204591Sluigi /* create a slot for this cl->S */ 673204591Sluigi qfq_slot_rotate(q, grp, roundedS); 674204591Sluigi /* group was surely ineligible, remove */ 675204591Sluigi __clear_bit(grp->index, &q->bitmaps[IR]); 676204591Sluigi __clear_bit(grp->index, &q->bitmaps[IB]); 677204591Sluigi } else if (!q->bitmaps[ER] && qfq_gt(roundedS, q->V)) 678204591Sluigi q->V = roundedS; 679204591Sluigi 680204591Sluigi grp->S = roundedS; 681204591Sluigi grp->F = roundedS + (2ULL << grp->slot_shift); // i.e. 2\sigma_i 682204591Sluigi s = qfq_calc_state(q, grp); 683204591Sluigi __set_bit(grp->index, &q->bitmaps[s]); 684204591Sluigi ND("new state %d 0x%x", s, q->bitmaps[s]); 685204591Sluigi ND("S %llx F %llx V %llx", cl->S, cl->F, q->V); 686204591Sluigiskip_update: 687204591Sluigi qfq_slot_insert(grp, cl, roundedS); 688204591Sluigi 689204591Sluigi return 0; 690204591Sluigi} 691204591Sluigi 692204591Sluigi 693204591Sluigi#if 0 694204591Sluigistatic inline void 695204591Sluigiqfq_slot_remove(struct qfq_sched *q, struct qfq_group *grp, 696204591Sluigi struct qfq_class *cl, struct qfq_class **pprev) 697204591Sluigi{ 698204591Sluigi unsigned int i, offset; 699204591Sluigi uint64_t roundedS; 700204591Sluigi 701204591Sluigi roundedS = qfq_round_down(cl->S, grp->slot_shift); 702204591Sluigi offset = (roundedS - grp->S) >> grp->slot_shift; 703204591Sluigi i = (grp->front + offset) % QFQ_MAX_SLOTS; 704204591Sluigi 705204591Sluigi#ifdef notyet 706204591Sluigi if (!pprev) { 707204591Sluigi pprev = &grp->slots[i]; 708204591Sluigi while (*pprev && *pprev != cl) 709204591Sluigi pprev = &(*pprev)->next; 710204591Sluigi } 711204591Sluigi#endif 712204591Sluigi 713204591Sluigi *pprev = cl->next; 714204591Sluigi if (!grp->slots[i]) 715204591Sluigi __clear_bit(offset, &grp->full_slots); 716204591Sluigi} 717204591Sluigi 718204591Sluigi/* 719204591Sluigi * called to forcibly destroy a queue. 720204591Sluigi * If the queue is not in the front bucket, or if it has 721204591Sluigi * other queues in the front bucket, we can simply remove 722204591Sluigi * the queue with no other side effects. 723204591Sluigi * Otherwise we must propagate the event up. 724204591Sluigi * XXX description to be completed. 725204591Sluigi */ 726204591Sluigistatic void 727204591Sluigiqfq_deactivate_class(struct qfq_sched *q, struct qfq_class *cl, 728204591Sluigi struct qfq_class **pprev) 729204591Sluigi{ 730204591Sluigi struct qfq_group *grp = &q->groups[cl->index]; 731204591Sluigi unsigned long mask; 732204591Sluigi uint64_t roundedS; 733204591Sluigi int s; 734204591Sluigi 735204591Sluigi cl->F = cl->S; // not needed if the class goes away. 736204591Sluigi qfq_slot_remove(q, grp, cl, pprev); 737204591Sluigi 738204591Sluigi if (!grp->full_slots) { 739204591Sluigi /* nothing left in the group, remove from all sets. 740204591Sluigi * Do ER last because if we were blocking other groups 741204591Sluigi * we must unblock them. 742204591Sluigi */ 743204591Sluigi __clear_bit(grp->index, &q->bitmaps[IR]); 744204591Sluigi __clear_bit(grp->index, &q->bitmaps[EB]); 745204591Sluigi __clear_bit(grp->index, &q->bitmaps[IB]); 746204591Sluigi 747204591Sluigi if (test_bit(grp->index, &q->bitmaps[ER]) && 748204591Sluigi !(q->bitmaps[ER] & ~((1UL << grp->index) - 1))) { 749204591Sluigi mask = q->bitmaps[ER] & ((1UL << grp->index) - 1); 750204591Sluigi if (mask) 751204591Sluigi mask = ~((1UL << __fls(mask)) - 1); 752204591Sluigi else 753204591Sluigi mask = ~0UL; 754204591Sluigi qfq_move_groups(q, mask, EB, ER); 755204591Sluigi qfq_move_groups(q, mask, IB, IR); 756204591Sluigi } 757204591Sluigi __clear_bit(grp->index, &q->bitmaps[ER]); 758204591Sluigi } else if (!grp->slots[grp->front]) { 759204591Sluigi cl = qfq_slot_scan(grp); 760204591Sluigi roundedS = qfq_round_down(cl->S, grp->slot_shift); 761204591Sluigi if (grp->S != roundedS) { 762204591Sluigi __clear_bit(grp->index, &q->bitmaps[ER]); 763204591Sluigi __clear_bit(grp->index, &q->bitmaps[IR]); 764204591Sluigi __clear_bit(grp->index, &q->bitmaps[EB]); 765204591Sluigi __clear_bit(grp->index, &q->bitmaps[IB]); 766204591Sluigi grp->S = roundedS; 767204591Sluigi grp->F = roundedS + (2ULL << grp->slot_shift); 768204591Sluigi s = qfq_calc_state(q, grp); 769204591Sluigi __set_bit(grp->index, &q->bitmaps[s]); 770204591Sluigi } 771204591Sluigi } 772204591Sluigi qfq_update_eligible(q, q->V); 773204591Sluigi} 774204591Sluigi#endif 775204591Sluigi 776204591Sluigistatic int 777204591Sluigiqfq_new_fsk(struct dn_fsk *f) 778204591Sluigi{ 779204591Sluigi ipdn_bound_var(&f->fs.par[0], 1, 1, QFQ_MAX_WEIGHT, "qfq weight"); 780204591Sluigi ipdn_bound_var(&f->fs.par[1], 1500, 1, 2000, "qfq maxlen"); 781204591Sluigi ND("weight %d len %d\n", f->fs.par[0], f->fs.par[1]); 782204591Sluigi return 0; 783204591Sluigi} 784204591Sluigi 785204591Sluigi/* 786204591Sluigi * initialize a new scheduler instance 787204591Sluigi */ 788204591Sluigistatic int 789204591Sluigiqfq_new_sched(struct dn_sch_inst *si) 790204591Sluigi{ 791204591Sluigi struct qfq_sched *q = (struct qfq_sched *)(si + 1); 792204591Sluigi struct qfq_group *grp; 793204591Sluigi int i; 794204591Sluigi 795204591Sluigi for (i = 0; i <= QFQ_MAX_INDEX; i++) { 796204591Sluigi grp = &q->groups[i]; 797204591Sluigi grp->index = i; 798204591Sluigi grp->slot_shift = QFQ_MTU_SHIFT + FRAC_BITS - 799204591Sluigi (QFQ_MAX_INDEX - i); 800204591Sluigi } 801204591Sluigi return 0; 802204591Sluigi} 803204591Sluigi 804204591Sluigi/* 805204591Sluigi * QFQ scheduler descriptor 806204591Sluigi */ 807204591Sluigistatic struct dn_alg qfq_desc = { 808204591Sluigi _SI( .type = ) DN_SCHED_QFQ, 809204591Sluigi _SI( .name = ) "QFQ", 810204591Sluigi _SI( .flags = ) DN_MULTIQUEUE, 811204591Sluigi 812204591Sluigi _SI( .schk_datalen = ) 0, 813204591Sluigi _SI( .si_datalen = ) sizeof(struct qfq_sched), 814204591Sluigi _SI( .q_datalen = ) sizeof(struct qfq_class) - sizeof(struct dn_queue), 815204591Sluigi 816204591Sluigi _SI( .enqueue = ) qfq_enqueue, 817204591Sluigi _SI( .dequeue = ) qfq_dequeue, 818204591Sluigi 819204591Sluigi _SI( .config = ) NULL, 820204591Sluigi _SI( .destroy = ) NULL, 821204591Sluigi _SI( .new_sched = ) qfq_new_sched, 822204591Sluigi _SI( .free_sched = ) NULL, 823204591Sluigi _SI( .new_fsk = ) qfq_new_fsk, 824204591Sluigi _SI( .free_fsk = ) NULL, 825204591Sluigi _SI( .new_queue = ) qfq_new_queue, 826204591Sluigi _SI( .free_queue = ) qfq_free_queue, 827204591Sluigi}; 828204591Sluigi 829204591SluigiDECLARE_DNSCHED_MODULE(dn_qfq, &qfq_desc); 830204591Sluigi 831204591Sluigi#ifdef QFQ_DEBUG 832204591Sluigistatic void 833204591Sluigidump_groups(struct qfq_sched *q, uint32_t mask) 834204591Sluigi{ 835204591Sluigi int i, j; 836204591Sluigi 837204591Sluigi for (i = 0; i < QFQ_MAX_INDEX + 1; i++) { 838204591Sluigi struct qfq_group *g = &q->groups[i]; 839204591Sluigi 840204591Sluigi if (0 == (mask & (1<<i))) 841204591Sluigi continue; 842204591Sluigi for (j = 0; j < QFQ_MAX_SLOTS; j++) { 843204591Sluigi if (g->slots[j]) 844204591Sluigi D(" bucket %d %p", j, g->slots[j]); 845204591Sluigi } 846204591Sluigi D("full_slots 0x%x", g->full_slots); 847204591Sluigi D(" %2d S 0x%20llx F 0x%llx %c", i, 848204591Sluigi g->S, g->F, 849204591Sluigi mask & (1<<i) ? '1' : '0'); 850204591Sluigi } 851204591Sluigi} 852204591Sluigi 853204591Sluigistatic void 854204591Sluigidump_sched(struct qfq_sched *q, const char *msg) 855204591Sluigi{ 856204591Sluigi D("--- in %s: ---", msg); 857204591Sluigi ND("loops %d queued %d V 0x%llx", q->loops, q->queued, q->V); 858204591Sluigi D(" ER 0x%08x", q->bitmaps[ER]); 859204591Sluigi D(" EB 0x%08x", q->bitmaps[EB]); 860204591Sluigi D(" IR 0x%08x", q->bitmaps[IR]); 861204591Sluigi D(" IB 0x%08x", q->bitmaps[IB]); 862204591Sluigi dump_groups(q, 0xffffffff); 863204591Sluigi}; 864204591Sluigi#endif /* QFQ_DEBUG */ 865