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-rw-r--r--third_party/nix/src/libutil/thread-pool.cc163
1 files changed, 0 insertions, 163 deletions
diff --git a/third_party/nix/src/libutil/thread-pool.cc b/third_party/nix/src/libutil/thread-pool.cc
deleted file mode 100644
index 7c6b0a1b469b..000000000000
--- a/third_party/nix/src/libutil/thread-pool.cc
+++ /dev/null
@@ -1,163 +0,0 @@
-#include "libutil/thread-pool.hh"
-
-#include <glog/logging.h>
-
-#include "libutil/affinity.hh"
-
-namespace nix {
-
-ThreadPool::ThreadPool(size_t _maxThreads) : maxThreads(_maxThreads) {
-  restoreAffinity();  // FIXME
-
-  if (maxThreads == 0u) {
-    maxThreads = std::thread::hardware_concurrency();
-    if (maxThreads == 0u) {
-      maxThreads = 1;
-    }
-  }
-
-  DLOG(INFO) << "starting pool of " << maxThreads - 1 << " threads";
-}
-
-ThreadPool::~ThreadPool() { shutdown(); }
-
-void ThreadPool::shutdown() {
-  std::vector<std::thread> workers;
-  {
-    auto state(state_.lock());
-    quit = true;
-    std::swap(workers, state->workers);
-  }
-
-  if (workers.empty()) {
-    return;
-  }
-
-  DLOG(INFO) << "reaping " << workers.size() << " worker threads";
-
-  work.notify_all();
-
-  for (auto& thr : workers) {
-    thr.join();
-  }
-}
-
-void ThreadPool::enqueue(const work_t& t) {
-  auto state(state_.lock());
-  if (quit) {
-    throw ThreadPoolShutDown(
-        "cannot enqueue a work item while the thread pool is shutting down");
-  }
-  state->pending.push(t);
-  /* Note: process() also executes items, so count it as a worker. */
-  if (state->pending.size() > state->workers.size() + 1 &&
-      state->workers.size() + 1 < maxThreads) {
-    state->workers.emplace_back(&ThreadPool::doWork, this, false);
-  }
-  work.notify_one();
-}
-
-void ThreadPool::process() {
-  state_.lock()->draining = true;
-
-  /* Do work until no more work is pending or active. */
-  try {
-    doWork(true);
-
-    auto state(state_.lock());
-
-    assert(quit);
-
-    if (state->exception) {
-      std::rethrow_exception(state->exception);
-    }
-
-  } catch (...) {
-    /* In the exceptional case, some workers may still be
-       active. They may be referencing the stack frame of the
-       caller. So wait for them to finish. (~ThreadPool also does
-       this, but it might be destroyed after objects referenced by
-       the work item lambdas.) */
-    shutdown();
-    throw;
-  }
-}
-
-void ThreadPool::doWork(bool mainThread) {
-  if (!mainThread) {
-    interruptCheck = [&]() { return (bool)quit; };
-  }
-
-  bool didWork = false;
-  std::exception_ptr exc;
-
-  while (true) {
-    work_t w;
-    {
-      auto state(state_.lock());
-
-      if (didWork) {
-        assert(state->active);
-        state->active--;
-
-        if (exc) {
-          if (!state->exception) {
-            state->exception = exc;
-            // Tell the other workers to quit.
-            quit = true;
-            work.notify_all();
-          } else {
-            /* Print the exception, since we can't
-               propagate it. */
-            try {
-              std::rethrow_exception(exc);
-            } catch (std::exception& e) {
-              if ((dynamic_cast<Interrupted*>(&e) == nullptr) &&
-                  (dynamic_cast<ThreadPoolShutDown*>(&e) == nullptr)) {
-                ignoreException();
-              }
-            } catch (...) {
-            }
-          }
-        }
-      }
-
-      /* Wait until a work item is available or we're asked to
-         quit. */
-      while (true) {
-        if (quit) {
-          return;
-        }
-
-        if (!state->pending.empty()) {
-          break;
-        }
-
-        /* If there are no active or pending items, and the
-           main thread is running process(), then no new items
-           can be added. So exit. */
-        if ((state->active == 0u) && state->draining) {
-          quit = true;
-          work.notify_all();
-          return;
-        }
-
-        state.wait(work);
-      }
-
-      w = std::move(state->pending.front());
-      state->pending.pop();
-      state->active++;
-    }
-
-    try {
-      w();
-    } catch (...) {
-      exc = std::current_exception();
-    }
-
-    didWork = true;
-  }
-}
-
-}  // namespace nix