xref: /aosp_15_r20/external/pigweed/pw_allocator/examples/spin_lock.cc (revision 61c4878ac05f98d0ceed94b57d316916de578985)
1 // Copyright 2024 The Pigweed Authors
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License"); you may not
4 // use this file except in compliance with the License. You may obtain a copy of
5 // the License at
6 //
7 //     https://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
11 // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
12 // License for the specific language governing permissions and limitations under
13 // the License.
14 
15 #include "examples/named_u32.h"
16 #include "pw_allocator/synchronized_allocator.h"
17 #include "pw_allocator/testing.h"
18 #include "pw_assert/check.h"
19 #include "pw_sync/interrupt_spin_lock.h"
20 #include "pw_thread/test_thread_context.h"
21 #include "pw_thread/thread.h"
22 #include "pw_thread/thread_core.h"
23 #include "pw_unit_test/framework.h"
24 
25 // TODO: https://pwbug.dev/365161669 - Express joinability as a build-system
26 // constraint.
27 #if PW_THREAD_JOINING_ENABLED
28 
29 namespace examples {
30 
31 /// Threaded task that performs several allocations.
32 class MyTask final {
33  public:
34   using Layout = pw::allocator::Layout;
35 
MyTask(pw::Allocator & allocator,const pw::thread::Options & options)36   MyTask(pw::Allocator& allocator, const pw::thread::Options& options)
37       : thread_core_(allocator) {
38     thread_ = pw::Thread(options, thread_core_);
39   }
40 
join()41   void join() { thread_.join(); }
42 
43  private:
44   class MyThreadCore : public pw::thread::ThreadCore {
45    public:
MyThreadCore(pw::Allocator & allocator)46     MyThreadCore(pw::Allocator& allocator) : allocator_(allocator) {}
47 
48    private:
Run()49     void Run() override {
50       std::array<NamedU32*, 10> values = {};
51       uint32_t counter = 0;
52       for (auto& value : values) {
53         void* ptr = allocator_.Allocate(Layout::Of<NamedU32>());
54         PW_CHECK_NOTNULL(ptr);
55         value = new (ptr) NamedU32("test", ++counter);
56       }
57       counter = 0;
58       for (auto& value : values) {
59         PW_CHECK_INT_EQ(value->value(), ++counter);
60         allocator_.Deallocate(value);
61       }
62     }
63 
64     pw::Allocator& allocator_;
65   } thread_core_;
66 
67   pw::Thread thread_;
68 };
69 
70 // DOCSTAG: [pw_allocator-examples-spin_lock]
RunTasks(pw::Allocator & allocator,const pw::thread::Options & options)71 void RunTasks(pw::Allocator& allocator, const pw::thread::Options& options) {
72   pw::allocator::SynchronizedAllocator<pw::sync::InterruptSpinLock> synced(
73       allocator);
74   MyTask task1(synced, options);
75   MyTask task2(synced, options);
76   task1.join();
77   task2.join();
78 }
79 // DOCSTAG: [pw_allocator-examples-spin_lock]
80 
81 }  // namespace examples
82 
83 namespace {
84 
85 using AllocatorForTest = ::pw::allocator::test::AllocatorForTest<2048>;
86 
TEST(SpinLockExample,RunTasks)87 TEST(SpinLockExample, RunTasks) {
88   // TODO: b/328831791 - This example did a nice job of uncovering some
89   // pathological fragmentation by `Block::AllocFirst`. Reduce the size of this
90   // allocator once that is addressed.
91   AllocatorForTest allocator;
92   pw::thread::test::TestThreadContext context;
93   examples::RunTasks(allocator, context.options());
94 }
95 
96 }  // namespace
97 
98 #endif  // PW_THREAD_JOINING_ENABLED
99