1 /*
2 Copyright (c) 2005-2023 Intel Corporation
3
4 Licensed under the Apache License, Version 2.0 (the "License");
5 you may not use this file except in compliance with the License.
6 You may obtain a copy of the License at
7
8 http://www.apache.org/licenses/LICENSE-2.0
9
10 Unless required by applicable law or agreed to in writing, software
11 distributed under the License is distributed on an "AS IS" BASIS,
12 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 See the License for the specific language governing permissions and
14 limitations under the License.
15 */
16
17 #include "arena.h"
18 #include "market.h"
19
20 #include <algorithm> // std::find
21
22 namespace tbb {
23 namespace detail {
24 namespace r1 {
25
26
27 class tbb_permit_manager_client : public pm_client {
28 public:
tbb_permit_manager_client(arena & a)29 tbb_permit_manager_client(arena& a) : pm_client(a) {}
30
register_thread()31 void register_thread() override {}
32
unregister_thread()33 void unregister_thread() override {}
34
set_allotment(unsigned allotment)35 void set_allotment(unsigned allotment) {
36 my_arena.set_allotment(allotment);
37 }
38 };
39
40 //------------------------------------------------------------------------
41 // market
42 //------------------------------------------------------------------------
43
market(unsigned workers_soft_limit)44 market::market(unsigned workers_soft_limit)
45 : my_num_workers_soft_limit(workers_soft_limit)
46 {}
47
create_client(arena & a)48 pm_client* market::create_client(arena& a) {
49 return new (cache_aligned_allocate(sizeof(tbb_permit_manager_client))) tbb_permit_manager_client(a);
50 }
51
register_client(pm_client * c,d1::constraints &)52 void market::register_client(pm_client* c, d1::constraints&) {
53 mutex_type::scoped_lock lock(my_mutex);
54 my_clients[c->priority_level()].push_back(c);
55 }
56
unregister_and_destroy_client(pm_client & c)57 void market::unregister_and_destroy_client(pm_client& c) {
58 {
59 mutex_type::scoped_lock lock(my_mutex);
60 auto& clients = my_clients[c.priority_level()];
61 auto it = std::find(clients.begin(), clients.end(), &c);
62 __TBB_ASSERT(it != clients.end(), "Destroying of an unregistered client");
63 clients.erase(it);
64 }
65
66 auto client = static_cast<tbb_permit_manager_client*>(&c);
67 client->~tbb_permit_manager_client();
68 cache_aligned_deallocate(client);
69 }
70
update_allotment()71 void market::update_allotment() {
72 int effective_soft_limit = my_mandatory_num_requested > 0 && my_num_workers_soft_limit == 0 ? 1 : my_num_workers_soft_limit;
73 int max_workers = min(my_total_demand, effective_soft_limit);
74 __TBB_ASSERT(max_workers >= 0, nullptr);
75
76 int unassigned_workers = max_workers;
77 int assigned = 0;
78 int carry = 0;
79 unsigned max_priority_level = num_priority_levels;
80 for (unsigned list_idx = 0; list_idx < num_priority_levels; ++list_idx ) {
81 int assigned_per_priority = min(my_priority_level_demand[list_idx], unassigned_workers);
82 unassigned_workers -= assigned_per_priority;
83 // We use reverse iterator there to serve last added clients first
84 for (auto it = my_clients[list_idx].rbegin(); it != my_clients[list_idx].rend(); ++it) {
85 tbb_permit_manager_client& client = static_cast<tbb_permit_manager_client&>(**it);
86 if (client.max_workers() == 0) {
87 client.set_allotment(0);
88 continue;
89 }
90
91 if (max_priority_level == num_priority_levels) {
92 max_priority_level = list_idx;
93 }
94
95 int allotted = 0;
96 if (my_num_workers_soft_limit == 0) {
97 __TBB_ASSERT(max_workers == 0 || max_workers == 1, nullptr);
98 allotted = client.min_workers() > 0 && assigned < max_workers ? 1 : 0;
99 } else {
100 int tmp = client.max_workers() * assigned_per_priority + carry;
101 allotted = tmp / my_priority_level_demand[list_idx];
102 carry = tmp % my_priority_level_demand[list_idx];
103 __TBB_ASSERT(allotted <= client.max_workers(), nullptr);
104 }
105 client.set_allotment(allotted);
106 client.set_top_priority(list_idx == max_priority_level);
107 assigned += allotted;
108 }
109 }
110 __TBB_ASSERT(assigned == max_workers, nullptr);
111 }
112
set_active_num_workers(int soft_limit)113 void market::set_active_num_workers(int soft_limit) {
114 mutex_type::scoped_lock lock(my_mutex);
115 if (my_num_workers_soft_limit != soft_limit) {
116 my_num_workers_soft_limit = soft_limit;
117 update_allotment();
118 }
119 }
120
adjust_demand(pm_client & c,int mandatory_delta,int workers_delta)121 void market::adjust_demand(pm_client& c, int mandatory_delta, int workers_delta) {
122 __TBB_ASSERT(-1 <= mandatory_delta && mandatory_delta <= 1, nullptr);
123
124 int delta{};
125 {
126 mutex_type::scoped_lock lock(my_mutex);
127 // Update client's state
128 delta = c.update_request(mandatory_delta, workers_delta);
129
130 // Update market's state
131 my_total_demand += delta;
132 my_priority_level_demand[c.priority_level()] += delta;
133 my_mandatory_num_requested += mandatory_delta;
134
135 update_allotment();
136 }
137
138 notify_thread_request(delta);
139 }
140
141 } // namespace r1
142 } // namespace detail
143 } // namespace tbb
144