diff options
Diffstat (limited to 'libbuild2/scheduler.cxx')
| -rw-r--r-- | libbuild2/scheduler.cxx | 29 |
1 files changed, 18 insertions, 11 deletions
diff --git a/libbuild2/scheduler.cxx b/libbuild2/scheduler.cxx index 437f904..bb56810 100644 --- a/libbuild2/scheduler.cxx +++ b/libbuild2/scheduler.cxx @@ -97,7 +97,7 @@ namespace build2 } void scheduler:: - deactivate () + deactivate (bool external) { if (max_active_ == 1) // Serial execution. return; @@ -106,6 +106,8 @@ namespace build2 active_--; waiting_++; + if (external) + external_++; progress_.fetch_add (1, memory_order_relaxed); if (waiting_ > stat_max_waiters_) @@ -122,7 +124,7 @@ namespace build2 { activate_helper (l); } - else if (active_ == 0) + else if (active_ == 0 && external_ == 0) { // Note that we tried to handle this directly in this thread but that // wouldn't work for the phase lock case where we cal; deactivate and @@ -135,7 +137,7 @@ namespace build2 } void scheduler:: - activate (bool collision) + activate (bool external, bool collision) { if (max_active_ == 1) // Serial execution. return; @@ -148,6 +150,8 @@ namespace build2 // If we have spare active threads, then become active. Otherwise it // enters the ready queue. // + if (external) + external_--; waiting_--; ready_++; progress_.fetch_add (1, memory_order_relaxed); @@ -166,7 +170,7 @@ namespace build2 void scheduler:: sleep (const duration& d) { - deactivate (); + deactivate (true /* external */); // MINGW GCC 4.9 doesn't implement this_thread so use Win32 Sleep(). // @@ -178,7 +182,7 @@ namespace build2 Sleep (static_cast<DWORD> (duration_cast<milliseconds> (d).count ())); #endif - activate (); + activate (true /* external */); } size_t scheduler:: @@ -190,7 +194,7 @@ namespace build2 // This thread is no longer active. // - deactivate (); + deactivate (false /* external */); // Note that the task count is checked while holding the lock. We also // have to notify while holding the lock (see resume()). The aim here @@ -227,7 +231,7 @@ namespace build2 // This thread is no longer waiting. // - activate (collision); + activate (false /* external */, collision); return tc; } @@ -465,6 +469,8 @@ namespace build2 l.lock (); } + assert (external_ == 0); + // Wait for the deadlock monitor (the only remaining thread). // if (orig_max_active_ != 1) // See tune() for why not max_active_. @@ -759,7 +765,7 @@ namespace build2 // if (s.ready_ != 0) s.ready_condv_.notify_one (); - else if (s.active_ == 0) + else if (s.active_ == 0 && s.external_ == 0) s.dead_condv_.notify_one (); } @@ -802,7 +808,7 @@ namespace build2 { s.dead_condv_.wait (l); - while (s.active_ == 0 && !s.shutdown_) + while (s.active_ == 0 && s.external_ == 0 && !s.shutdown_) { // We may have a deadlock which can happen because of dependency // cycles. @@ -829,9 +835,10 @@ namespace build2 } l.lock (); - // Re-check active count for good measure (maybe spinning too fast). + // Re-check active/external counts for good measure (maybe we are + // spinning too fast). // - if (np == op && s.active_ == 0 && !s.shutdown_) + if (np == op && s.active_ == 0 && s.external_ == 0 && !s.shutdown_) { // Shutting things down cleanly is tricky: we could have handled it // in the scheduler (e.g., by setting a flag and then waking |