Commit Graph

4 Commits

Author SHA1 Message Date
Shilei Tian 03ff643d2e [OpenMP] Put old APIs back and added new _async series for backward compatibility
Summary: According to comments on bi-weekly meeting, this patch put back old APIs and added new `_async` series

Reviewers: jdoerfert

Reviewed By: jdoerfert

Subscribers: yaxunl, guansong, openmp-commits

Tags: #openmp

Differential Revision: https://reviews.llvm.org/D77822
2020-04-09 22:40:58 -04:00
Shilei Tian 32ed29271f [OpenMP] Optimized stream selection by scheduling data mapping for the same target region into a same stream
Summary:
This patch introduces two things for offloading:
1. Asynchronous data transferring: those functions are suffix with `_async`. They have one more argument compared with their synchronous counterparts: `__tgt_async_info*`, which is a new struct that only has one field, `void *Identifier`. This struct is for information exchange between different asynchronous operations. It can be used for stream selection, like in this case, or operation synchronization, which is also used. We may expect more usages in the future.
2. Optimization of stream selection for data mapping. Previous implementation was using asynchronous device memory transfer but synchronizing after each memory transfer. Actually, if we say kernel A needs four memory copy to device and two memory copy back to host, then we can schedule these seven operations (four H2D, two D2H, and one kernel launch) into a same stream and just need synchronization after memory copy from device to host. In this way, we can save a huge overhead compared with synchronization after each operation.

Reviewers: jdoerfert, ye-luo

Reviewed By: jdoerfert

Subscribers: yaxunl, lildmh, guansong, openmp-commits

Tags: #openmp

Differential Revision: https://reviews.llvm.org/D77005
2020-04-07 14:55:47 -04:00
Gheorghe-Teodor Bercea c5fe030c16 [OpenMP][libomptarget] Enable usage of unified memory for declare target link variables
Summary: This patch enables the usage of a host variable on the device for declare target link variables when unified memory is available.

Reviewers: ABataev, caomhin, grokos

Reviewed By: grokos

Subscribers: Hahnfeld, guansong, jdoerfert, openmp-commits

Tags: #openmp

Differential Revision: https://reviews.llvm.org/D60884

llvm-svn: 362505
2019-06-04 15:05:53 +00:00
George Rokos 3de4cd1281 [OpenMP] Initial implementation of OpenMP offloading library - libomptarget plugins.
This is the patch upstreaming the plugins part of libomptarget (CUDA, generic-elf-64).

Differential Revision: https://reviews.llvm.org/D14253

llvm-svn: 293724
2017-02-01 00:14:41 +00:00