ShuriZma
/
xenia
mirror of https://github.com/xenia-project/xenia.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Preventing (one of likely many) race condition with ringbuffer. 

This was causing acks for commands not executed if the CPU ran faster
than the GPU.
This commit is contained in:
Ben Vanik 2013-10-13 12:17:07 -07:00
parent 41a652dd03
commit e0af361d74
2 changed files with 15 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
src/xenia/gpu/ring_buffer_worker.cc
View File

@ -75,7 +75,11 @@ void RingBufferWorker::Pump() {
return;
}
}
if (read_ptr_index_ == write_ptr_index_) {
// Bring local so we don't have to worry about them changing out from under
// us.
uint32_t write_ptr_index = write_ptr_index_;
if (read_ptr_index_ == write_ptr_index) {
return;
}
@ -84,11 +88,11 @@ void RingBufferWorker::Pump() {
// TODO(benvanik): handle wrapping around
// read_ptr_index_ = (read_ptr_index_ + 1) % (primary_buffer_size_ / 4);
XEASSERT(write_ptr_index_ > read_ptr_index_);
uint32_t length = write_ptr_index_ - read_ptr_index_;
XEASSERT(write_ptr_index > read_ptr_index_);
uint32_t length = write_ptr_index - read_ptr_index_;
if (length) {
ExecuteSegment(primary_buffer_ptr_ + read_ptr_index_ * 4, length);
read_ptr_index_ = write_ptr_index_;
read_ptr_index_ = write_ptr_index;
}
// TODO(benvanik): use read_ptr_update_freq_ and only issue after moving

2
src/xenia/gpu/ring_buffer_worker.h
View File

@ -51,7 +51,7 @@ protected:
uint32_t read_ptr_writeback_ptr_;
HANDLE write_ptr_index_event_;
uint32_t write_ptr_index_;
volatile uint32_t write_ptr_index_;
};