878 lines
23 KiB
C
878 lines
23 KiB
C
/*
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* Copyright (c) 2010 Fabio Checconi, Luigi Rizzo, Paolo Valente
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* All rights reserved
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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/*
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* $FreeBSD$
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*/
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#ifdef _KERNEL
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#include <sys/malloc.h>
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#include <sys/socket.h>
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#include <sys/socketvar.h>
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#include <sys/kernel.h>
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#include <sys/mbuf.h>
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#include <sys/module.h>
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#include <net/if.h> /* IFNAMSIZ */
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#include <netinet/in.h>
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#include <netinet/ip_var.h> /* ipfw_rule_ref */
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#include <netinet/ip_fw.h> /* flow_id */
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#include <netinet/ip_dummynet.h>
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#include <netpfil/ipfw/dn_heap.h>
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#include <netpfil/ipfw/ip_dn_private.h>
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#include <netpfil/ipfw/dn_sched.h>
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#else
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#include <dn_test.h>
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#endif
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#ifdef QFQ_DEBUG
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#define _P64 unsigned long long /* cast for printing uint64_t */
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struct qfq_sched;
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static void dump_sched(struct qfq_sched *q, const char *msg);
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#define NO(x) x
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#else
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#define NO(x)
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#endif
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#define DN_SCHED_QFQ 4 // XXX Where?
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typedef unsigned long bitmap;
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/*
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* bitmaps ops are critical. Some linux versions have __fls
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* and the bitmap ops. Some machines have ffs
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* NOTE: fls() returns 1 for the least significant bit,
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* __fls() returns 0 for the same case.
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* We use the base-0 version __fls() to match the description in
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* the ToN QFQ paper
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*/
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#if defined(_WIN32) || (defined(__MIPSEL__) && defined(LINUX_24))
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int fls(unsigned int n)
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{
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int i = 0;
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for (i = 0; n > 0; n >>= 1, i++)
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;
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return i;
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}
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#endif
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#if !defined(_KERNEL) || defined( __FreeBSD__ ) || defined(_WIN32) || (defined(__MIPSEL__) && defined(LINUX_24))
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static inline unsigned long __fls(unsigned long word)
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{
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return fls(word) - 1;
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}
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#endif
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#if !defined(_KERNEL) || !defined(__linux__)
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#ifdef QFQ_DEBUG
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static int test_bit(int ix, bitmap *p)
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{
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if (ix < 0 || ix > 31)
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D("bad index %d", ix);
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return *p & (1<<ix);
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}
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static void __set_bit(int ix, bitmap *p)
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{
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if (ix < 0 || ix > 31)
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D("bad index %d", ix);
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*p |= (1<<ix);
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}
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static void __clear_bit(int ix, bitmap *p)
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{
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if (ix < 0 || ix > 31)
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D("bad index %d", ix);
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*p &= ~(1<<ix);
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}
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#else /* !QFQ_DEBUG */
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/* XXX do we have fast version, or leave it to the compiler ? */
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#define test_bit(ix, pData) ((*pData) & (1<<(ix)))
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#define __set_bit(ix, pData) (*pData) |= (1<<(ix))
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#define __clear_bit(ix, pData) (*pData) &= ~(1<<(ix))
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#endif /* !QFQ_DEBUG */
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#endif /* !__linux__ */
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#ifdef __MIPSEL__
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#define __clear_bit(ix, pData) (*pData) &= ~(1<<(ix))
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#endif
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/*-------------------------------------------*/
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/*
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Virtual time computations.
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S, F and V are all computed in fixed point arithmetic with
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FRAC_BITS decimal bits.
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QFQ_MAX_INDEX is the maximum index allowed for a group. We need
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one bit per index.
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QFQ_MAX_WSHIFT is the maximum power of two supported as a weight.
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The layout of the bits is as below:
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[ MTU_SHIFT ][ FRAC_BITS ]
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[ MAX_INDEX ][ MIN_SLOT_SHIFT ]
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^.__grp->index = 0
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*.__grp->slot_shift
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where MIN_SLOT_SHIFT is derived by difference from the others.
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The max group index corresponds to Lmax/w_min, where
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Lmax=1<<MTU_SHIFT, w_min = 1 .
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From this, and knowing how many groups (MAX_INDEX) we want,
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we can derive the shift corresponding to each group.
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Because we often need to compute
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F = S + len/w_i and V = V + len/wsum
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instead of storing w_i store the value
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inv_w = (1<<FRAC_BITS)/w_i
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so we can do F = S + len * inv_w * wsum.
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We use W_TOT in the formulas so we can easily move between
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static and adaptive weight sum.
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The per-scheduler-instance data contain all the data structures
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for the scheduler: bitmaps and bucket lists.
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*/
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/*
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* Maximum number of consecutive slots occupied by backlogged classes
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* inside a group. This is approx lmax/lmin + 5.
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* XXX check because it poses constraints on MAX_INDEX
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*/
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#define QFQ_MAX_SLOTS 32
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/*
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* Shifts used for class<->group mapping. Class weights are
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* in the range [1, QFQ_MAX_WEIGHT], we to map each class i to the
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* group with the smallest index that can support the L_i / r_i
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* configured for the class.
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*
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* grp->index is the index of the group; and grp->slot_shift
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* is the shift for the corresponding (scaled) sigma_i.
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*
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* When computing the group index, we do (len<<FP_SHIFT)/weight,
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* then compute an FLS (which is like a log2()), and if the result
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* is below the MAX_INDEX region we use 0 (which is the same as
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* using a larger len).
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*/
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#define QFQ_MAX_INDEX 19
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#define QFQ_MAX_WSHIFT 16 /* log2(max_weight) */
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#define QFQ_MAX_WEIGHT (1<<QFQ_MAX_WSHIFT)
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#define QFQ_MAX_WSUM (2*QFQ_MAX_WEIGHT)
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#define FRAC_BITS 30 /* fixed point arithmetic */
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#define ONE_FP (1UL << FRAC_BITS)
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#define QFQ_MTU_SHIFT 11 /* log2(max_len) */
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#define QFQ_MIN_SLOT_SHIFT (FRAC_BITS + QFQ_MTU_SHIFT - QFQ_MAX_INDEX)
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/*
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* Possible group states, also indexes for the bitmaps array in
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* struct qfq_queue. We rely on ER, IR, EB, IB being numbered 0..3
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*/
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enum qfq_state { ER, IR, EB, IB, QFQ_MAX_STATE };
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struct qfq_group;
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/*
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* additional queue info. Some of this info should come from
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* the flowset, we copy them here for faster processing.
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* This is an overlay of the struct dn_queue
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*/
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struct qfq_class {
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struct dn_queue _q;
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uint64_t S, F; /* flow timestamps (exact) */
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struct qfq_class *next; /* Link for the slot list. */
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/* group we belong to. In principle we would need the index,
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* which is log_2(lmax/weight), but we never reference it
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* directly, only the group.
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*/
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struct qfq_group *grp;
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/* these are copied from the flowset. */
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uint32_t inv_w; /* ONE_FP/weight */
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uint32_t lmax; /* Max packet size for this flow. */
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};
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/* Group descriptor, see the paper for details.
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* Basically this contains the bucket lists
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*/
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struct qfq_group {
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uint64_t S, F; /* group timestamps (approx). */
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unsigned int slot_shift; /* Slot shift. */
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unsigned int index; /* Group index. */
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unsigned int front; /* Index of the front slot. */
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bitmap full_slots; /* non-empty slots */
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/* Array of lists of active classes. */
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struct qfq_class *slots[QFQ_MAX_SLOTS];
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};
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/* scheduler instance descriptor. */
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struct qfq_sched {
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uint64_t V; /* Precise virtual time. */
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uint32_t wsum; /* weight sum */
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uint32_t iwsum; /* inverse weight sum */
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NO(uint32_t i_wsum;) /* ONE_FP/w_sum */
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NO(uint32_t queued;) /* debugging */
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NO(uint32_t loops;) /* debugging */
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bitmap bitmaps[QFQ_MAX_STATE]; /* Group bitmaps. */
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struct qfq_group groups[QFQ_MAX_INDEX + 1]; /* The groups. */
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};
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/*---- support functions ----------------------------*/
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/* Generic comparison function, handling wraparound. */
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static inline int qfq_gt(uint64_t a, uint64_t b)
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{
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return (int64_t)(a - b) > 0;
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}
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/* Round a precise timestamp to its slotted value. */
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static inline uint64_t qfq_round_down(uint64_t ts, unsigned int shift)
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{
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return ts & ~((1ULL << shift) - 1);
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}
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/* return the pointer to the group with lowest index in the bitmap */
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static inline struct qfq_group *qfq_ffs(struct qfq_sched *q,
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unsigned long bitmap)
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{
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int index = ffs(bitmap) - 1; // zero-based
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return &q->groups[index];
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}
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/*
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* Calculate a flow index, given its weight and maximum packet length.
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* index = log_2(maxlen/weight) but we need to apply the scaling.
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* This is used only once at flow creation.
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*/
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static int qfq_calc_index(uint32_t inv_w, unsigned int maxlen)
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{
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uint64_t slot_size = (uint64_t)maxlen *inv_w;
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unsigned long size_map;
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int index = 0;
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size_map = (unsigned long)(slot_size >> QFQ_MIN_SLOT_SHIFT);
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if (!size_map)
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goto out;
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index = __fls(size_map) + 1; // basically a log_2()
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index -= !(slot_size - (1ULL << (index + QFQ_MIN_SLOT_SHIFT - 1)));
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if (index < 0)
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index = 0;
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out:
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ND("W = %d, L = %d, I = %d\n", ONE_FP/inv_w, maxlen, index);
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return index;
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}
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/*---- end support functions ----*/
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/*-------- API calls --------------------------------*/
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/*
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* Validate and copy parameters from flowset.
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*/
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static int
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qfq_new_queue(struct dn_queue *_q)
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{
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struct qfq_sched *q = (struct qfq_sched *)(_q->_si + 1);
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struct qfq_class *cl = (struct qfq_class *)_q;
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int i;
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uint32_t w; /* approximated weight */
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/* import parameters from the flowset. They should be correct
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* already.
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*/
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w = _q->fs->fs.par[0];
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cl->lmax = _q->fs->fs.par[1];
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if (!w || w > QFQ_MAX_WEIGHT) {
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w = 1;
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D("rounding weight to 1");
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}
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cl->inv_w = ONE_FP/w;
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w = ONE_FP/cl->inv_w;
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if (q->wsum + w > QFQ_MAX_WSUM)
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return EINVAL;
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i = qfq_calc_index(cl->inv_w, cl->lmax);
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cl->grp = &q->groups[i];
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q->wsum += w;
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q->iwsum = ONE_FP / q->wsum; /* XXX note theory */
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// XXX cl->S = q->V; ?
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return 0;
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}
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/* remove an empty queue */
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static int
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qfq_free_queue(struct dn_queue *_q)
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{
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struct qfq_sched *q = (struct qfq_sched *)(_q->_si + 1);
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struct qfq_class *cl = (struct qfq_class *)_q;
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if (cl->inv_w) {
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q->wsum -= ONE_FP/cl->inv_w;
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if (q->wsum != 0)
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q->iwsum = ONE_FP / q->wsum;
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cl->inv_w = 0; /* reset weight to avoid run twice */
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}
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return 0;
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}
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/* Calculate a mask to mimic what would be ffs_from(). */
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static inline unsigned long
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mask_from(unsigned long bitmap, int from)
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{
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return bitmap & ~((1UL << from) - 1);
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}
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/*
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* The state computation relies on ER=0, IR=1, EB=2, IB=3
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* First compute eligibility comparing grp->S, q->V,
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* then check if someone is blocking us and possibly add EB
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*/
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static inline unsigned int
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qfq_calc_state(struct qfq_sched *q, struct qfq_group *grp)
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{
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/* if S > V we are not eligible */
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unsigned int state = qfq_gt(grp->S, q->V);
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unsigned long mask = mask_from(q->bitmaps[ER], grp->index);
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struct qfq_group *next;
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if (mask) {
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next = qfq_ffs(q, mask);
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if (qfq_gt(grp->F, next->F))
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state |= EB;
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}
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return state;
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}
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/*
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* In principle
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* q->bitmaps[dst] |= q->bitmaps[src] & mask;
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* q->bitmaps[src] &= ~mask;
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* but we should make sure that src != dst
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*/
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static inline void
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qfq_move_groups(struct qfq_sched *q, unsigned long mask, int src, int dst)
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{
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q->bitmaps[dst] |= q->bitmaps[src] & mask;
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q->bitmaps[src] &= ~mask;
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}
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static inline void
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qfq_unblock_groups(struct qfq_sched *q, int index, uint64_t old_finish)
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{
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unsigned long mask = mask_from(q->bitmaps[ER], index + 1);
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struct qfq_group *next;
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if (mask) {
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next = qfq_ffs(q, mask);
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if (!qfq_gt(next->F, old_finish))
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return;
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}
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mask = (1UL << index) - 1;
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qfq_move_groups(q, mask, EB, ER);
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qfq_move_groups(q, mask, IB, IR);
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}
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/*
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* perhaps
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*
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old_V ^= q->V;
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old_V >>= QFQ_MIN_SLOT_SHIFT;
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if (old_V) {
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...
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}
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*
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*/
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static inline void
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qfq_make_eligible(struct qfq_sched *q, uint64_t old_V)
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{
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unsigned long mask, vslot, old_vslot;
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vslot = q->V >> QFQ_MIN_SLOT_SHIFT;
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old_vslot = old_V >> QFQ_MIN_SLOT_SHIFT;
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if (vslot != old_vslot) {
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/* must be 2ULL, see ToN QFQ article fig.5, we use base-0 fls */
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mask = (2ULL << (__fls(vslot ^ old_vslot))) - 1;
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qfq_move_groups(q, mask, IR, ER);
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qfq_move_groups(q, mask, IB, EB);
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}
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}
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/*
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* XXX we should make sure that slot becomes less than 32.
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* This is guaranteed by the input values.
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* roundedS is always cl->S rounded on grp->slot_shift bits.
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*/
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static inline void
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qfq_slot_insert(struct qfq_group *grp, struct qfq_class *cl, uint64_t roundedS)
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{
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uint64_t slot = (roundedS - grp->S) >> grp->slot_shift;
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unsigned int i = (grp->front + slot) % QFQ_MAX_SLOTS;
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cl->next = grp->slots[i];
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grp->slots[i] = cl;
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__set_bit(slot, &grp->full_slots);
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}
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/*
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* remove the entry from the slot
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*/
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static inline void
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qfq_front_slot_remove(struct qfq_group *grp)
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{
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struct qfq_class **h = &grp->slots[grp->front];
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*h = (*h)->next;
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if (!*h)
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__clear_bit(0, &grp->full_slots);
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}
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/*
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* Returns the first full queue in a group. As a side effect,
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* adjust the bucket list so the first non-empty bucket is at
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* position 0 in full_slots.
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*/
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static inline struct qfq_class *
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qfq_slot_scan(struct qfq_group *grp)
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{
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int i;
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ND("grp %d full %x", grp->index, grp->full_slots);
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if (!grp->full_slots)
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return NULL;
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i = ffs(grp->full_slots) - 1; // zero-based
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if (i > 0) {
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grp->front = (grp->front + i) % QFQ_MAX_SLOTS;
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grp->full_slots >>= i;
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}
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return grp->slots[grp->front];
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}
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/*
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* adjust the bucket list. When the start time of a group decreases,
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* we move the index down (modulo QFQ_MAX_SLOTS) so we don't need to
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* move the objects. The mask of occupied slots must be shifted
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* because we use ffs() to find the first non-empty slot.
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* This covers decreases in the group's start time, but what about
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* increases of the start time ?
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* Here too we should make sure that i is less than 32
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*/
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static inline void
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qfq_slot_rotate(struct qfq_sched *q, struct qfq_group *grp, uint64_t roundedS)
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{
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unsigned int i = (grp->S - roundedS) >> grp->slot_shift;
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|
|
(void)q;
|
|
grp->full_slots <<= i;
|
|
grp->front = (grp->front - i) % QFQ_MAX_SLOTS;
|
|
}
|
|
|
|
|
|
static inline void
|
|
qfq_update_eligible(struct qfq_sched *q, uint64_t old_V)
|
|
{
|
|
bitmap ineligible;
|
|
|
|
ineligible = q->bitmaps[IR] | q->bitmaps[IB];
|
|
if (ineligible) {
|
|
if (!q->bitmaps[ER]) {
|
|
struct qfq_group *grp;
|
|
grp = qfq_ffs(q, ineligible);
|
|
if (qfq_gt(grp->S, q->V))
|
|
q->V = grp->S;
|
|
}
|
|
qfq_make_eligible(q, old_V);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Updates the class, returns true if also the group needs to be updated.
|
|
*/
|
|
static inline int
|
|
qfq_update_class(struct qfq_sched *q, struct qfq_group *grp,
|
|
struct qfq_class *cl)
|
|
{
|
|
|
|
(void)q;
|
|
cl->S = cl->F;
|
|
if (cl->_q.mq.head == NULL) {
|
|
qfq_front_slot_remove(grp);
|
|
} else {
|
|
unsigned int len;
|
|
uint64_t roundedS;
|
|
|
|
len = cl->_q.mq.head->m_pkthdr.len;
|
|
cl->F = cl->S + (uint64_t)len * cl->inv_w;
|
|
roundedS = qfq_round_down(cl->S, grp->slot_shift);
|
|
if (roundedS == grp->S)
|
|
return 0;
|
|
|
|
qfq_front_slot_remove(grp);
|
|
qfq_slot_insert(grp, cl, roundedS);
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static struct mbuf *
|
|
qfq_dequeue(struct dn_sch_inst *si)
|
|
{
|
|
struct qfq_sched *q = (struct qfq_sched *)(si + 1);
|
|
struct qfq_group *grp;
|
|
struct qfq_class *cl;
|
|
struct mbuf *m;
|
|
uint64_t old_V;
|
|
|
|
NO(q->loops++;)
|
|
if (!q->bitmaps[ER]) {
|
|
NO(if (q->queued)
|
|
dump_sched(q, "start dequeue");)
|
|
return NULL;
|
|
}
|
|
|
|
grp = qfq_ffs(q, q->bitmaps[ER]);
|
|
|
|
cl = grp->slots[grp->front];
|
|
/* extract from the first bucket in the bucket list */
|
|
m = dn_dequeue(&cl->_q);
|
|
|
|
if (!m) {
|
|
D("BUG/* non-workconserving leaf */");
|
|
return NULL;
|
|
}
|
|
NO(q->queued--;)
|
|
old_V = q->V;
|
|
q->V += (uint64_t)m->m_pkthdr.len * q->iwsum;
|
|
ND("m is %p F 0x%llx V now 0x%llx", m, cl->F, q->V);
|
|
|
|
if (qfq_update_class(q, grp, cl)) {
|
|
uint64_t old_F = grp->F;
|
|
cl = qfq_slot_scan(grp);
|
|
if (!cl) { /* group gone, remove from ER */
|
|
__clear_bit(grp->index, &q->bitmaps[ER]);
|
|
// grp->S = grp->F + 1; // XXX debugging only
|
|
} else {
|
|
uint64_t roundedS = qfq_round_down(cl->S, grp->slot_shift);
|
|
unsigned int s;
|
|
|
|
if (grp->S == roundedS)
|
|
goto skip_unblock;
|
|
grp->S = roundedS;
|
|
grp->F = roundedS + (2ULL << grp->slot_shift);
|
|
/* remove from ER and put in the new set */
|
|
__clear_bit(grp->index, &q->bitmaps[ER]);
|
|
s = qfq_calc_state(q, grp);
|
|
__set_bit(grp->index, &q->bitmaps[s]);
|
|
}
|
|
/* we need to unblock even if the group has gone away */
|
|
qfq_unblock_groups(q, grp->index, old_F);
|
|
}
|
|
|
|
skip_unblock:
|
|
qfq_update_eligible(q, old_V);
|
|
NO(if (!q->bitmaps[ER] && q->queued)
|
|
dump_sched(q, "end dequeue");)
|
|
|
|
return m;
|
|
}
|
|
|
|
/*
|
|
* Assign a reasonable start time for a new flow k in group i.
|
|
* Admissible values for \hat(F) are multiples of \sigma_i
|
|
* no greater than V+\sigma_i . Larger values mean that
|
|
* we had a wraparound so we consider the timestamp to be stale.
|
|
*
|
|
* If F is not stale and F >= V then we set S = F.
|
|
* Otherwise we should assign S = V, but this may violate
|
|
* the ordering in ER. So, if we have groups in ER, set S to
|
|
* the F_j of the first group j which would be blocking us.
|
|
* We are guaranteed not to move S backward because
|
|
* otherwise our group i would still be blocked.
|
|
*/
|
|
static inline void
|
|
qfq_update_start(struct qfq_sched *q, struct qfq_class *cl)
|
|
{
|
|
unsigned long mask;
|
|
uint64_t limit, roundedF;
|
|
int slot_shift = cl->grp->slot_shift;
|
|
|
|
roundedF = qfq_round_down(cl->F, slot_shift);
|
|
limit = qfq_round_down(q->V, slot_shift) + (1ULL << slot_shift);
|
|
|
|
if (!qfq_gt(cl->F, q->V) || qfq_gt(roundedF, limit)) {
|
|
/* timestamp was stale */
|
|
mask = mask_from(q->bitmaps[ER], cl->grp->index);
|
|
if (mask) {
|
|
struct qfq_group *next = qfq_ffs(q, mask);
|
|
if (qfq_gt(roundedF, next->F)) {
|
|
/* from pv 71261956973ba9e0637848a5adb4a5819b4bae83 */
|
|
if (qfq_gt(limit, next->F))
|
|
cl->S = next->F;
|
|
else /* preserve timestamp correctness */
|
|
cl->S = limit;
|
|
return;
|
|
}
|
|
}
|
|
cl->S = q->V;
|
|
} else { /* timestamp is not stale */
|
|
cl->S = cl->F;
|
|
}
|
|
}
|
|
|
|
static int
|
|
qfq_enqueue(struct dn_sch_inst *si, struct dn_queue *_q, struct mbuf *m)
|
|
{
|
|
struct qfq_sched *q = (struct qfq_sched *)(si + 1);
|
|
struct qfq_group *grp;
|
|
struct qfq_class *cl = (struct qfq_class *)_q;
|
|
uint64_t roundedS;
|
|
int s;
|
|
|
|
NO(q->loops++;)
|
|
DX(4, "len %d flow %p inv_w 0x%x grp %d", m->m_pkthdr.len,
|
|
_q, cl->inv_w, cl->grp->index);
|
|
/* XXX verify that the packet obeys the parameters */
|
|
if (m != _q->mq.head) {
|
|
if (dn_enqueue(_q, m, 0)) /* packet was dropped */
|
|
return 1;
|
|
NO(q->queued++;)
|
|
if (m != _q->mq.head)
|
|
return 0;
|
|
}
|
|
/* If reach this point, queue q was idle */
|
|
grp = cl->grp;
|
|
qfq_update_start(q, cl); /* adjust start time */
|
|
/* compute new finish time and rounded start. */
|
|
cl->F = cl->S + (uint64_t)(m->m_pkthdr.len) * cl->inv_w;
|
|
roundedS = qfq_round_down(cl->S, grp->slot_shift);
|
|
|
|
/*
|
|
* insert cl in the correct bucket.
|
|
* If cl->S >= grp->S we don't need to adjust the
|
|
* bucket list and simply go to the insertion phase.
|
|
* Otherwise grp->S is decreasing, we must make room
|
|
* in the bucket list, and also recompute the group state.
|
|
* Finally, if there were no flows in this group and nobody
|
|
* was in ER make sure to adjust V.
|
|
*/
|
|
if (grp->full_slots) {
|
|
if (!qfq_gt(grp->S, cl->S))
|
|
goto skip_update;
|
|
/* create a slot for this cl->S */
|
|
qfq_slot_rotate(q, grp, roundedS);
|
|
/* group was surely ineligible, remove */
|
|
__clear_bit(grp->index, &q->bitmaps[IR]);
|
|
__clear_bit(grp->index, &q->bitmaps[IB]);
|
|
} else if (!q->bitmaps[ER] && qfq_gt(roundedS, q->V))
|
|
q->V = roundedS;
|
|
|
|
grp->S = roundedS;
|
|
grp->F = roundedS + (2ULL << grp->slot_shift); // i.e. 2\sigma_i
|
|
s = qfq_calc_state(q, grp);
|
|
__set_bit(grp->index, &q->bitmaps[s]);
|
|
ND("new state %d 0x%x", s, q->bitmaps[s]);
|
|
ND("S %llx F %llx V %llx", cl->S, cl->F, q->V);
|
|
skip_update:
|
|
qfq_slot_insert(grp, cl, roundedS);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
#if 0
|
|
static inline void
|
|
qfq_slot_remove(struct qfq_sched *q, struct qfq_group *grp,
|
|
struct qfq_class *cl, struct qfq_class **pprev)
|
|
{
|
|
unsigned int i, offset;
|
|
uint64_t roundedS;
|
|
|
|
roundedS = qfq_round_down(cl->S, grp->slot_shift);
|
|
offset = (roundedS - grp->S) >> grp->slot_shift;
|
|
i = (grp->front + offset) % QFQ_MAX_SLOTS;
|
|
|
|
#ifdef notyet
|
|
if (!pprev) {
|
|
pprev = &grp->slots[i];
|
|
while (*pprev && *pprev != cl)
|
|
pprev = &(*pprev)->next;
|
|
}
|
|
#endif
|
|
|
|
*pprev = cl->next;
|
|
if (!grp->slots[i])
|
|
__clear_bit(offset, &grp->full_slots);
|
|
}
|
|
|
|
/*
|
|
* called to forcibly destroy a queue.
|
|
* If the queue is not in the front bucket, or if it has
|
|
* other queues in the front bucket, we can simply remove
|
|
* the queue with no other side effects.
|
|
* Otherwise we must propagate the event up.
|
|
* XXX description to be completed.
|
|
*/
|
|
static void
|
|
qfq_deactivate_class(struct qfq_sched *q, struct qfq_class *cl,
|
|
struct qfq_class **pprev)
|
|
{
|
|
struct qfq_group *grp = &q->groups[cl->index];
|
|
unsigned long mask;
|
|
uint64_t roundedS;
|
|
int s;
|
|
|
|
cl->F = cl->S; // not needed if the class goes away.
|
|
qfq_slot_remove(q, grp, cl, pprev);
|
|
|
|
if (!grp->full_slots) {
|
|
/* nothing left in the group, remove from all sets.
|
|
* Do ER last because if we were blocking other groups
|
|
* we must unblock them.
|
|
*/
|
|
__clear_bit(grp->index, &q->bitmaps[IR]);
|
|
__clear_bit(grp->index, &q->bitmaps[EB]);
|
|
__clear_bit(grp->index, &q->bitmaps[IB]);
|
|
|
|
if (test_bit(grp->index, &q->bitmaps[ER]) &&
|
|
!(q->bitmaps[ER] & ~((1UL << grp->index) - 1))) {
|
|
mask = q->bitmaps[ER] & ((1UL << grp->index) - 1);
|
|
if (mask)
|
|
mask = ~((1UL << __fls(mask)) - 1);
|
|
else
|
|
mask = ~0UL;
|
|
qfq_move_groups(q, mask, EB, ER);
|
|
qfq_move_groups(q, mask, IB, IR);
|
|
}
|
|
__clear_bit(grp->index, &q->bitmaps[ER]);
|
|
} else if (!grp->slots[grp->front]) {
|
|
cl = qfq_slot_scan(grp);
|
|
roundedS = qfq_round_down(cl->S, grp->slot_shift);
|
|
if (grp->S != roundedS) {
|
|
__clear_bit(grp->index, &q->bitmaps[ER]);
|
|
__clear_bit(grp->index, &q->bitmaps[IR]);
|
|
__clear_bit(grp->index, &q->bitmaps[EB]);
|
|
__clear_bit(grp->index, &q->bitmaps[IB]);
|
|
grp->S = roundedS;
|
|
grp->F = roundedS + (2ULL << grp->slot_shift);
|
|
s = qfq_calc_state(q, grp);
|
|
__set_bit(grp->index, &q->bitmaps[s]);
|
|
}
|
|
}
|
|
qfq_update_eligible(q, q->V);
|
|
}
|
|
#endif
|
|
|
|
static int
|
|
qfq_new_fsk(struct dn_fsk *f)
|
|
{
|
|
ipdn_bound_var(&f->fs.par[0], 1, 1, QFQ_MAX_WEIGHT, "qfq weight");
|
|
ipdn_bound_var(&f->fs.par[1], 1500, 1, 2000, "qfq maxlen");
|
|
ND("weight %d len %d\n", f->fs.par[0], f->fs.par[1]);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* initialize a new scheduler instance
|
|
*/
|
|
static int
|
|
qfq_new_sched(struct dn_sch_inst *si)
|
|
{
|
|
struct qfq_sched *q = (struct qfq_sched *)(si + 1);
|
|
struct qfq_group *grp;
|
|
int i;
|
|
|
|
for (i = 0; i <= QFQ_MAX_INDEX; i++) {
|
|
grp = &q->groups[i];
|
|
grp->index = i;
|
|
grp->slot_shift = QFQ_MTU_SHIFT + FRAC_BITS -
|
|
(QFQ_MAX_INDEX - i);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* QFQ scheduler descriptor
|
|
*/
|
|
static struct dn_alg qfq_desc = {
|
|
_SI( .type = ) DN_SCHED_QFQ,
|
|
_SI( .name = ) "QFQ",
|
|
_SI( .flags = ) DN_MULTIQUEUE,
|
|
|
|
_SI( .schk_datalen = ) 0,
|
|
_SI( .si_datalen = ) sizeof(struct qfq_sched),
|
|
_SI( .q_datalen = ) sizeof(struct qfq_class) - sizeof(struct dn_queue),
|
|
|
|
_SI( .enqueue = ) qfq_enqueue,
|
|
_SI( .dequeue = ) qfq_dequeue,
|
|
|
|
_SI( .config = ) NULL,
|
|
_SI( .destroy = ) NULL,
|
|
_SI( .new_sched = ) qfq_new_sched,
|
|
_SI( .free_sched = ) NULL,
|
|
_SI( .new_fsk = ) qfq_new_fsk,
|
|
_SI( .free_fsk = ) NULL,
|
|
_SI( .new_queue = ) qfq_new_queue,
|
|
_SI( .free_queue = ) qfq_free_queue,
|
|
};
|
|
|
|
DECLARE_DNSCHED_MODULE(dn_qfq, &qfq_desc);
|
|
|
|
#ifdef QFQ_DEBUG
|
|
static void
|
|
dump_groups(struct qfq_sched *q, uint32_t mask)
|
|
{
|
|
int i, j;
|
|
|
|
for (i = 0; i < QFQ_MAX_INDEX + 1; i++) {
|
|
struct qfq_group *g = &q->groups[i];
|
|
|
|
if (0 == (mask & (1<<i)))
|
|
continue;
|
|
for (j = 0; j < QFQ_MAX_SLOTS; j++) {
|
|
if (g->slots[j])
|
|
D(" bucket %d %p", j, g->slots[j]);
|
|
}
|
|
D("full_slots 0x%llx", (_P64)g->full_slots);
|
|
D(" %2d S 0x%20llx F 0x%llx %c", i,
|
|
(_P64)g->S, (_P64)g->F,
|
|
mask & (1<<i) ? '1' : '0');
|
|
}
|
|
}
|
|
|
|
static void
|
|
dump_sched(struct qfq_sched *q, const char *msg)
|
|
{
|
|
D("--- in %s: ---", msg);
|
|
D("loops %d queued %d V 0x%llx", q->loops, q->queued, (_P64)q->V);
|
|
D(" ER 0x%08x", (unsigned)q->bitmaps[ER]);
|
|
D(" EB 0x%08x", (unsigned)q->bitmaps[EB]);
|
|
D(" IR 0x%08x", (unsigned)q->bitmaps[IR]);
|
|
D(" IB 0x%08x", (unsigned)q->bitmaps[IB]);
|
|
dump_groups(q, 0xffffffff);
|
|
};
|
|
#endif /* QFQ_DEBUG */
|