2 * Copyright (c) 2016 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
17 #error do not include tw_timer_template.h directly
20 #include <vppinfra/clib.h>
21 #include <vppinfra/pool.h>
24 #define _twt(a,b) a##b##_t
25 #define __twt(a,b) _twt(a,b)
26 #define TWT(a) __twt(a,TW_SUFFIX)
29 #define __tw(a,b) _tw(a,b)
30 #define TW(a) __tw(a,TW_SUFFIX)
34 @brief TW timer template header file, do not compile directly
36 Instantiation of tw_timer_template.h generates named structures to
37 implement specific timer wheel geometries. Choices include: number of
38 timer wheels (currently, 1 or 2), number of slots per ring (a power of
39 two), and the number of timers per "object handle".
41 Internally, user object/timer handles are 32-bit integers, so if one
42 selects 16 timers/object (4 bits), the resulting timer wheel handle is
43 limited to 2**28 objects.
45 Here are the specific settings required to generate a single 2048 slot
46 wheel which supports 2 timers per object:
48 #define TW_TIMER_WHEELS 1
49 #define TW_SLOTS_PER_RING 2048
50 #define TW_RING_SHIFT 11
51 #define TW_RING_MASK (TW_SLOTS_PER_RING -1)
52 #define TW_TIMERS_PER_OBJECT 2
53 #define LOG2_TW_TIMERS_PER_OBJECT 1
54 #define TW_SUFFIX _2t_1w_2048sl
56 See tw_timer_2t_1w_2048sl.h for a complete
59 tw_timer_template.h is not intended to be #included directly. Client
60 codes can include multiple timer geometry header files, although
61 extreme caution would required to use the TW and TWT macros in such a
66 Initialize a two-timer, single 2048-slot wheel w/ a 1-second
69 tw_timer_wheel_init_2t_1w_2048sl (&tm->single_wheel,
70 expired_timer_single_callback,
71 1.0 / * timer interval * / );
75 handle = tw_timer_start_2t_1w_2048sl (&tm->single_wheel, elt_index,
76 [0 | 1] / * timer id * / ,
77 expiration_time_in_u32_ticks);
81 tw_timer_stop_2t_1w_2048sl (&tm->single_wheel, handle);
83 Expired timer callback:
86 expired_timer_single_callback (u32 * expired_timers)
89 u32 pool_index, timer_id;
90 tw_timer_test_elt_t *e;
91 tw_timer_test_main_t *tm = &tw_timer_test_main;
93 for (i = 0; i < vec_len (expired_timers);
95 pool_index = expired_timers[i] & 0x7FFFFFFF;
96 timer_id = expired_timers[i] >> 31;
98 ASSERT (timer_id == 1);
100 e = pool_elt_at_index (tm->test_elts, pool_index);
102 if (e->expected_to_expire != tm->single_wheel.current_tick)
104 fformat (stdout, "[%d] expired at %d not %d\n",
105 e - tm->test_elts, tm->single_wheel.current_tick,
106 e->expected_to_expire);
108 pool_put (tm->test_elts, e);
113 #if (TW_TIMER_WHEELS != 1 && TW_TIMER_WHEELS != 2 && TW_TIMER_WHEELS != 3)
114 #error TW_TIMER_WHEELS must be 1, 2 or 3
119 /** next, previous pool indices */
127 #if (TW_TIMER_WHEELS == 3)
128 /** fast ring offset, only valid in the slow ring */
129 u16 fast_ring_offset;
130 /** slow ring offset, only valid in the glacier ring */
131 u16 slow_ring_offset;
133 #if (TW_TIMER_WHEELS == 2)
134 /** fast ring offset, only valid in the slow ring */
135 u16 fast_ring_offset;
136 /** slow ring offset, only valid in the glacier ring */
141 #if (TW_OVERFLOW_VECTOR > 0)
146 /** user timer handle */
151 * These structures ar used by all geometries,
152 * so they need a private #include block...
154 #ifndef __defined_tw_timer_wheel_slot__
155 #define __defined_tw_timer_wheel_slot__
158 /** Listhead of timers which expire in this interval */
160 } tw_timer_wheel_slot_t;
163 /** Fast timer ring ID */
165 /** Slow timer ring ID */
167 /** Glacier ring ID */
168 TW_TIMER_RING_GLACIER,
170 #endif /* __defined_tw_timer_wheel_slot__ */
175 TWT (tw_timer) * timers;
177 /** Next time the wheel should run */
180 /** Last time the wheel ran */
183 /** Timer ticks per second */
184 f64 ticks_per_second;
186 /** Timer interval, also needed to avoid fp divide in speed path */
192 /** first expiration time */
193 u64 first_expires_tick;
195 /** current wheel indices */
196 u32 current_index[TW_TIMER_WHEELS];
199 tw_timer_wheel_slot_t w[TW_TIMER_WHEELS][TW_SLOTS_PER_RING];
201 #if TW_OVERFLOW_VECTOR > 0
202 tw_timer_wheel_slot_t overflow;
205 /** expired timer callback, receives a vector of handles */
206 void (*expired_timer_callback) (u32 * expired_timer_handles);
208 /** vector of expired timers */
209 u32 *expired_timer_handles;
211 /** maximum expirations */
213 } TWT (tw_timer_wheel);
215 u32 TW (tw_timer_start) (TWT (tw_timer_wheel) * tw,
216 u32 pool_index, u32 timer_id, u64 interval);
218 void TW (tw_timer_stop) (TWT (tw_timer_wheel) * tw, u32 handle);
220 void TW (tw_timer_wheel_init) (TWT (tw_timer_wheel) * tw,
221 void *expired_timer_callback,
222 f64 timer_interval, u32 max_expirations);
224 void TW (tw_timer_wheel_free) (TWT (tw_timer_wheel) * tw);
226 u32 *TW (tw_timer_expire_timers) (TWT (tw_timer_wheel) * tw, f64 now);
227 u32 *TW (tw_timer_expire_timers_vec) (TWT (tw_timer_wheel) * tw, f64 now,
231 * fd.io coding-style-patch-verification: ON
234 * eval: (c-set-style "gnu")