xref: /xnu-8792.61.2/bsd/net/classq/classq_fq_codel.h (revision 42e220869062b56f8d7d0726fd4c88954f87902c)
1 /*
2  * Copyright (c) 2016-2021 Apple Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23  * Please see the License for the specific language governing rights and
24  * limitations under the License.
25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 
29 #ifndef _NET_CLASSQ_CLASSQ_FQ_CODEL_H
30 #define _NET_CLASSQ_CLASSQ_FQ_CODEL_H
31 #ifdef PRIVATE
32 #ifdef BSD_KERNEL_PRIVATE
33 #include <stdbool.h>
34 #include <sys/time.h>
35 #include <net/flowadv.h>
36 #include <net/classq/if_classq.h>
37 #if SKYWALK
38 #include <skywalk/os_skywalk_private.h>
39 #endif /* SKYWALK */
40 
41 #ifdef __cplusplus
42 extern "C" {
43 #endif
44 
45 #define AQM_KTRACE_AON_FLOW_HIGH_DELAY    AQMDBG_CODE(DBG_AQM_ALWAYSON, 0x001)
46 #define AQM_KTRACE_AON_THROTTLE           AQMDBG_CODE(DBG_AQM_ALWAYSON, 0x002)
47 #define AQM_KTRACE_AON_FLOW_OVERWHELMING  AQMDBG_CODE(DBG_AQM_ALWAYSON, 0x003)
48 #define AQM_KTRACE_AON_FLOW_DQ_STALL      AQMDBG_CODE(DBG_AQM_ALWAYSON, 0x004)
49 
50 #define AQM_KTRACE_STATS_FLOW_ENQUEUE   AQMDBG_CODE(DBG_AQM_STATS, 0x001)
51 #define AQM_KTRACE_STATS_FLOW_DEQUEUE   AQMDBG_CODE(DBG_AQM_STATS, 0x002)
52 #define AQM_KTRACE_STATS_FLOW_CTL       AQMDBG_CODE(DBG_AQM_STATS, 0x003)
53 #define AQM_KTRACE_STATS_FLOW_ALLOC     AQMDBG_CODE(DBG_AQM_STATS, 0x004)
54 #define AQM_KTRACE_STATS_FLOW_DESTROY   AQMDBG_CODE(DBG_AQM_STATS, 0x005)
55 
56 #define AQM_KTRACE_FQ_GRP_SC_IDX(_fq_) \
57 	((_fq_)->fq_group->fqg_index << 4 | (_fq_)->fq_sc_index)
58 
59 #define FQ_MIN_FC_THRESHOLD_BYTES       7500
60 #define FQ_IS_DELAY_HIGH(_fq_)   ((_fq_)->fq_flags & FQF_DELAY_HIGH)
61 #define FQ_SET_DELAY_HIGH(_fq_) do {                          \
62     if (!FQ_IS_DELAY_HIGH(_fq_)) {                              \
63 	KDBG(AQM_KTRACE_AON_FLOW_HIGH_DELAY | DBG_FUNC_START, \
64 	    (_fq_)->fq_flowhash, AQM_KTRACE_FQ_GRP_SC_IDX((_fq_)),    \
65 	    (_fq_)->fq_bytes, (_fq_)->fq_min_qdelay);                 \
66     }                                                                 \
67     (_fq_)->fq_flags |= FQF_DELAY_HIGH; \
68     } while (0)
69 #define FQ_CLEAR_DELAY_HIGH(_fq_) do { \
70     if (FQ_IS_DELAY_HIGH(_fq_)) {        \
71 	    KDBG(AQM_KTRACE_AON_FLOW_HIGH_DELAY | DBG_FUNC_END, \
72 	            (_fq_)->fq_flowhash, AQM_KTRACE_FQ_GRP_SC_IDX((_fq_)),  \
73 	            (_fq_)->fq_bytes, (_fq_)->fq_min_qdelay);               \
74     }                                                       \
75     (_fq_)->fq_flags &= ~FQF_DELAY_HIGH;                    \
76 } while (0)
77 
78 #define FQ_IS_OVERWHELMING(_fq_)   ((_fq_)->fq_flags & FQF_OVERWHELMING)
79 #define FQ_SET_OVERWHELMING(_fq_) do { \
80 	if (!FQ_IS_OVERWHELMING(_fq_)) {                              \
81 	        KDBG(AQM_KTRACE_AON_FLOW_OVERWHELMING | DBG_FUNC_START, \
82 	                        (_fq_)->fq_flowhash, AQM_KTRACE_FQ_GRP_SC_IDX((_fq_)),    \
83 	                        (_fq_)->fq_bytes, (_fq_)->fq_min_qdelay);                 \
84 	}                                                                                                                                         \
85 	(_fq_)->fq_flags |= FQF_OVERWHELMING; \
86 } while (0)
87 #define FQ_CLEAR_OVERWHELMING(_fq_) do { \
88 	if (FQ_IS_OVERWHELMING(_fq_)) {                              \
89 	        KDBG(AQM_KTRACE_AON_FLOW_OVERWHELMING | DBG_FUNC_END,  \
90 	                        (_fq_)->fq_flowhash, AQM_KTRACE_FQ_GRP_SC_IDX((_fq_)),    \
91 	                        (_fq_)->fq_bytes, (_fq_)->fq_min_qdelay);                 \
92 	}                                                                                     \
93 	(_fq_)->fq_flags &= ~FQF_OVERWHELMING; \
94 } while (0)
95 
96 /*
97  * time (in ns) the flow queue can stay in empty state.
98  */
99 #define FQ_EMPTY_PURGE_DELAY    (3ULL * 1000 * 1000 * 1000)
100 
101 /*
102  * maximum number of flow queues which can be purged during a dequeue.
103  */
104 #define FQ_EMPTY_PURGE_MAX      4
105 
106 struct flowq {
107 #pragma pack(push,1)
108 	union {
109 		MBUFQ_HEAD(mbufq_head) __mbufq; /* mbuf packet queue */
110 #if SKYWALK
111 		KPKTQ_HEAD(kpktq_head) __kpktq; /* skywalk packet queue */
112 #endif /* SKYWALK */
113 	} __fq_pktq_u;
114 #pragma pack(pop)
115 	uint32_t       fq_flowhash;    /* Flow hash */
116 	uint32_t       fq_bytes;       /* Number of bytes in the queue */
117 	int32_t        fq_deficit;     /* Deficit for scheduling */
118 	fq_if_group_t  *fq_group;          /* Back pointer to the group */
119 #define FQF_FLOWCTL_CAPABLE 0x01 /* Use flow control instead of drop */
120 #define FQF_DELAY_HIGH  0x02    /* Min delay is greater than target */
121 #define FQF_NEW_FLOW    0x04    /* Currently on new flows queue */
122 #define FQF_OLD_FLOW    0x08    /* Currently on old flows queue */
123 #define FQF_FLOWCTL_ON  0x10    /* Currently flow controlled */
124 #define FQF_EMPTY_FLOW  0x20    /* Currently on empty flows queue */
125 #define FQF_OVERWHELMING  0x40  /* The largest flow when AQM hits queue limit */
126 	uint8_t        fq_flags;       /* flags */
127 	uint8_t        fq_sc_index; /* service_class index */
128 	bool           fq_in_dqlist;
129 	fq_tfc_type_t  fq_tfc_type;
130 	uint8_t        __fq_pad_uint8[4];
131 	uint64_t       fq_min_qdelay; /* min queue delay for Codel */
132 	uint64_t       fq_getqtime;    /* last dequeue time */
133 	union {
134 		uint64_t   fq_updatetime; /* next update interval */
135 		/* empty list purge time (in nanoseconds) */
136 		uint64_t   fq_empty_purge_time;
137 	};
138 	SLIST_ENTRY(flowq) fq_hashlink; /* for flow queue hash table */
139 	/*
140 	 * flow queue will only be on either one of the lists.
141 	 */
142 	union {
143 		STAILQ_ENTRY(flowq) fq_actlink; /* for new/old flow queues */
144 		/* entry on empty flow queue list */
145 		TAILQ_ENTRY(flowq) fq_empty_link;
146 	};
147 	/* entry on dequeue flow list */
148 	STAILQ_ENTRY(flowq) fq_dqlink;
149 	/* temporary packet queue for dequeued packets */
150 	classq_pkt_t   fq_dq_head;
151 	classq_pkt_t   fq_dq_tail;
152 };
153 
154 typedef struct flowq fq_t;
155 
156 #define FQF_FLOW_STATE_MASK    (FQF_DELAY_HIGH | FQF_NEW_FLOW | \
157     FQF_OLD_FLOW | FQF_FLOWCTL_ON | FQF_EMPTY_FLOW)
158 
159 #define fq_mbufq        __fq_pktq_u.__mbufq
160 #if SKYWALK
161 #define fq_kpktq        __fq_pktq_u.__kpktq
162 #endif /* SKYWALK */
163 
164 #if SKYWALK
165 #define fq_empty(_q, _ptype)    (((_ptype) == QP_MBUF) ?  \
166     MBUFQ_EMPTY(&(_q)->fq_mbufq) : KPKTQ_EMPTY(&(_q)->fq_kpktq))
167 #else /* !SKYWALK */
168 #define fq_empty(_q, _ptype)    MBUFQ_EMPTY(&(_q)->fq_mbufq)
169 #endif /* !SKYWALK */
170 
171 #if SKYWALK
172 #define fq_enqueue(_q, _h, _t, _c, _ptype) do {                         \
173 	switch (_ptype) {                                               \
174 	case QP_MBUF:                                                   \
175 	        ASSERT((_h).cp_ptype == QP_MBUF);                       \
176 	        ASSERT((_t).cp_ptype == QP_MBUF);                       \
177 	        MBUFQ_ENQUEUE_MULTI(&(_q)->fq_mbufq, (_h).cp_mbuf,      \
178 	            (_t).cp_mbuf);                                      \
179 	        MBUFQ_ADD_CRUMB_MULTI(&(_q)->fq_mbufq, (_h).cp_mbuf,    \
180 	            (_t).cp_mbuf, PKT_CRUMB_FQ_ENQUEUE);                \
181 	        break;                                                  \
182 	case QP_PACKET:                                                 \
183 	        ASSERT((_h).cp_ptype == QP_PACKET);                     \
184 	        ASSERT((_t).cp_ptype == QP_PACKET);                     \
185 	        KPKTQ_ENQUEUE_MULTI(&(_q)->fq_kpktq, (_h).cp_kpkt,      \
186 	            (_t).cp_kpkt, (_c));                                \
187 	        break;                                                  \
188 	default:                                                        \
189 	        VERIFY(0);                                              \
190 	        __builtin_unreachable();                                \
191 	        break;                                                  \
192 	}                                                               \
193 } while (0)
194 #else /* !SKYWALK */
195 #define fq_enqueue(_q, _h, _t, _c, _ptype) {                            \
196     MBUFQ_ENQUEUE_MULTI(&(_q)->fq_mbufq, (_h).cp_mbuf, (_t).cp_mbuf);   \
197     MBUFQ_ADD_CRUMB_MULTI(&(_q)->fq_mbufq, (_h).cp_mbuf,                \
198 	    (_t).cp_mbuf, PKT_CRUMB_FQ_ENQUEUE);                        \
199 } while (0)
200 #endif /* !SKYWALK */
201 
202 #if SKYWALK
203 #define fq_dequeue(_q, _p, _ptype) do {                                 \
204 	switch (_ptype) {                                               \
205 	case QP_MBUF: {                                                 \
206 	        MBUFQ_DEQUEUE(&(_q)->fq_mbufq, (_p)->cp_mbuf);          \
207 	        if (__probable((_p)->cp_mbuf != NULL)) {                \
208 	                CLASSQ_PKT_INIT_MBUF((_p), (_p)->cp_mbuf);      \
209 	                m_add_crumb((_p)->cp_mbuf,                      \
210 	                    PKT_CRUMB_FQ_DEQUEUE);                      \
211 	        }                                                       \
212 	        break;                                                  \
213 	}                                                               \
214 	case QP_PACKET: {                                               \
215 	        KPKTQ_DEQUEUE(&(_q)->fq_kpktq, (_p)->cp_kpkt);          \
216 	        if (__probable((_p)->cp_kpkt != NULL)) {                \
217 	                CLASSQ_PKT_INIT_PACKET((_p), (_p)->cp_kpkt);    \
218 	        }                                                       \
219 	        break;                                                  \
220 	}                                                               \
221 	default:                                                        \
222 	        VERIFY(0);                                              \
223 	        __builtin_unreachable();                                \
224 	        break;                                                  \
225 	}                                                               \
226 } while (0)
227 #else /* !SKYWALK */
228 #define fq_dequeue(_q, _p, _ptype) do {                                 \
229 	MBUFQ_DEQUEUE(&(_q)->fq_mbufq, (_p)->cp_mbuf);                  \
230 	if (__probable((_p)->cp_mbuf != NULL)) {                        \
231 	        CLASSQ_PKT_INIT_MBUF((_p), (_p)->cp_mbuf);              \
232 	        m_add_crumb((_p)->cp_mbuf, PKT_CRUMB_FQ_DEQUEUE);       \
233 	}                                                               \
234 } while (0)
235 #endif /* !SKYWALK */
236 
237 struct fq_codel_sched_data;
238 struct fq_if_classq;
239 
240 /* Function definitions */
241 extern void fq_codel_init(void);
242 extern void fq_codel_reap_caches(boolean_t);
243 extern fq_t *fq_alloc(classq_pkt_type_t);
244 extern void fq_destroy(fq_t *, classq_pkt_type_t);
245 extern int fq_addq(struct fq_codel_sched_data *, fq_if_group_t *,
246     pktsched_pkt_t *, struct fq_if_classq *);
247 extern void fq_getq_flow(struct fq_codel_sched_data *, fq_t *,
248     pktsched_pkt_t *, uint64_t now);
249 extern void fq_codel_dequeue(fq_if_t *fqs, fq_t *fq,
250     pktsched_pkt_t *pkt, uint64_t now);
251 extern void fq_getq_flow_internal(struct fq_codel_sched_data *,
252     fq_t *, pktsched_pkt_t *);
253 extern void fq_head_drop(struct fq_codel_sched_data *, fq_t *);
254 
255 #ifdef __cplusplus
256 }
257 #endif
258 #endif /* BSD_KERNEL_PRIVATE */
259 #endif /* PRIVATE */
260 #endif /* _NET_CLASSQ_CLASSQ_FQ_CODEL_H */
261