Android mainline 11.0.0 release 20
Add OWNERS am: 412dbb6a44 am: ae9ca1488e am: ef0a4791fc

Change-Id: I4539af9b177b2015f9e82858e3c75718e19c48ec
tree: 2f0410d095e95822edec068f49766b74d0374ee9
  1. bench/
  2. cmake/
  3. examples/
  4. include/
  5. src/
  6. test/
  7. .gitignore
  8. .travis.yml
  9. Android.bp
  10. CMakeLists.txt
  11. configure.py
  12. confu.yaml
  13. LICENSE
  14. METADATA
  15. MODULE_LICENSE_BSD
  16. OWNERS
  17. README.md
  18. TEST_MAPPING
README.md

pthreadpool

BSD (2 clause) License Build Status

pthreadpool is a portable and efficient thread pool implementation. It provides similar functionality to #pragma omp parallel for, but with additional features.

Features:

  • C interface (C++-compatible).
  • 1D-6D loops with step parameters.
  • Run on user-specified or auto-detected number of threads.
  • Work-stealing scheduling for efficient work balancing.
  • Wait-free synchronization of work items.
  • Compatible with Linux (including Android), macOS, iOS, Emscripten, Native Client environments.
  • 100% unit tests coverage.
  • Throughput and latency microbenchmarks.

Example

The following example demonstates using the thread pool for parallel addition of two arrays:

static void add_arrays(struct array_addition_context* context, size_t i) {
  context->sum[i] = context->augend[i] + context->addend[i];
}

#define ARRAY_SIZE 4

int main() {
  double augend[ARRAY_SIZE] = { 1.0, 2.0, 4.0, -5.0 };
  double addend[ARRAY_SIZE] = { 0.25, -1.75, 0.0, 0.5 };
  double sum[ARRAY_SIZE];

  pthreadpool_t threadpool = pthreadpool_create(0);
  assert(threadpool != NULL);
  
  const size_t threads_count = pthreadpool_get_threads_count(threadpool);
  printf("Created thread pool with %zu threads\n", threads_count);

  struct array_addition_context context = { augend, addend, sum };
  pthreadpool_parallelize_1d(threadpool,
    (pthreadpool_task_1d_t) add_arrays,
    (void**) &context,
    ARRAY_SIZE,
    PTHREADPOOL_FLAG_DISABLE_DENORMALS /* flags */);
  
  pthreadpool_destroy(threadpool);
  threadpool = NULL;

  printf("%8s\t%.2lf\t%.2lf\t%.2lf\t%.2lf\n", "Augend",
    augend[0], augend[1], augend[2], augend[3]);
  printf("%8s\t%.2lf\t%.2lf\t%.2lf\t%.2lf\n", "Addend",
    addend[0], addend[1], addend[2], addend[3]);
  printf("%8s\t%.2lf\t%.2lf\t%.2lf\t%.2lf\n", "Sum",
    sum[0], sum[1], sum[2], sum[3]);

  return 0;
}