Commit Graph

20 Commits

Author SHA1 Message Date
Shilei Tian 4031bb982b [OpenMP] Refined CUDA plugin to put all CUDA operations into class
Summary: Current implementation mixed everything up so that there is almost no encapsulation. In this patch, all CUDA related operations are put into a new class DeviceRTLTy and only necessary functions are exposed. In addition, all C++ code now conforms with LLVM code standard, keeping those API functions following C style.

Reviewers: jdoerfert

Reviewed By: jdoerfert

Subscribers: jfb, yaxunl, guansong, openmp-commits

Tags: #openmp

Differential Revision: https://reviews.llvm.org/D77951
2020-04-13 13:32:46 -04:00
Shilei Tian feed674dec [OpenMP] Introduce stream pool to make sure the correctness of device synchr...
...onization

Summary: In previous patch, in order to optimize performance, we only synchronize once
for each target region. The syncrhonization is via stream synchronization.
However, in the extreme situation, the performce might be bad. Consider the
following case: There is a task that requires transferring huge amount of data
(call many times of data transferring function). It is scheduled to the first
stream. And then we have 255 very light tasks scheduled to the remaining 255
streams (by default we have 256 streams). They can be finished before we do
synchronization at the end of the first task. Next, we get another very huge
task. It will be scheduled again to the first stream. Now the first task
finishes its kernel launch and call stream synchronization. Right now, the
stream already contains two kernels, and the synchronization will wait until the
two kernels finish instead of just the first one for the first task.

In this patch, we introduce stream pool. After each synchronization, the stream
will be returned back to the pool to make sure that for each synchronization,
only expected operations are waited.

Reviewers: jdoerfert

Reviewed By: jdoerfert

Subscribers: gregrodgers, yaxunl, lildmh, guansong, openmp-commits

Tags: #openmp

Differential Revision: https://reviews.llvm.org/D77412
2020-04-11 07:08:56 -04:00
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
Johannes Doerfert a5153dbc36 [OpenMP][Offloading] Added support for multiple streams so that multiple kernels can be executed concurrently
Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D74145
2020-02-11 22:07:14 -06:00
Kazuaki Ishizaki 4c6a098ad5 [OpenMP] NFC: Fix trivial typos in comments
Reviewers: jdoerfert, Jim

Reviewed By: Jim

Subscribers: Jim, mgorny, guansong, jfb, openmp-commits

Tags: #openmp

Differential Revision: https://reviews.llvm.org/D72285
2020-01-07 14:05:03 +08:00
Ron Lieberman dc34b1c94d Test commit: adds a . to comment. NFC 2019-11-04 16:51:03 -06:00
Michael Kruse 78769ec403 [libomptarget] Harmonize emitting CUDA errors and general debug messages.
Ensures that CUDA fail reasons (such as "No CUDA-capable device detected")
are printed together with libomptarget's debug message
(e.g. "Error when setting CUDA context"). Previously, the former was
printed only in CMAKE_BUILD_TYPE=Debug builds while the latter was
enabled by LIBOMPTARGET_ENABLE_DEBUG.

With this change, also only call cuGetErrorString when the error will be
printed.

Suggested-by: Ye Luo <xw111luoye@gmail.com>

Differential Revision: https://reviews.llvm.org/D65687

llvm-svn: 367910
2019-08-05 19:12:10 +00:00
Gheorghe-Teodor Bercea aace6d285d [OpenMP][libomptarget] Add support for declare target to clause under unified memory
Summary:
This patch adds support for handling variables under the:

```
#pragma omp declare target to()
```

clause when the 

```
#pragma omp requires unified_shared_memory
```

is used.

The address of the host variable is copied into the device pointer just like for the declare target link case.

Reviewers: ABataev, caomhin, grokos, AlexEichenberger

Reviewed By: grokos

Subscribers: jcownie, guansong, jdoerfert, openmp-commits

Tags: #openmp

Differential Revision: https://reviews.llvm.org/D63106

llvm-svn: 363825
2019-06-19 15:48:10 +00:00
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
Chandler Carruth 57b08b0944 Update more file headers across all of the LLVM projects in the monorepo
to reflect the new license. These used slightly different spellings that
defeated my regular expressions.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351648
2019-01-19 10:56:40 +00:00
Jonas Hahnfeld bb51d39871 [libomptarget][CUDA] Use cuDeviceGetAttribute, NFCI.
cuDeviceGetProperties has apparently been deprecated since CUDA 5.0.
Nvidia started using annotations only in CUDA 9.2, so nobody noticed
nor cared before.
The new function returns the same values, tested with a P100.

Differential Revision: https://reviews.llvm.org/D51624

llvm-svn: 341372
2018-09-04 15:13:28 +00:00
Alexey Bataev 2622e9e5b3 [OPENMP, NVPTX] Support several images in the executable.
Summary:
Currently Cuda plugin supports loading of the single image, though we
may have the executable with the several images, if it has target
regions inside of the dynamically loaded library. Patch allows to load
multiple images.

Reviewers: grokos

Subscribers: guansong, openmp-commits, kkwli0

Differential Revision: https://reviews.llvm.org/D49036

llvm-svn: 336569
2018-07-09 17:46:55 +00:00
Guansong Zhang e1c7a46d5b [OpenMP] Use LIBOMPTARGET_DEVICE_RTL_DEBUG env var to control debug messages on the device side
Summary:
Enable the device side debug messages at compile time, use env var to control at runtime.

To achieve this, an environment data block is passed to the device lib when it is loaded.

By default, the message is off, to enable it, a user need to set LIBOMPDEVICE_DEBUG=1.

Reviewers: grokos

Reviewed By: grokos

Subscribers: openmp-commits

Tags: #openmp

Differential Revision: https://reviews.llvm.org/D46210

llvm-svn: 331550
2018-05-04 19:29:28 +00:00
Jonas Hahnfeld c189523529 [libomptarget] Only use CUDA Driver API
Use equivalents for the last calls to the Runtime API. Remove
stray assert in case of an error found during review, we should
only return OFFLOAD_FAIL.

Differential Revision: https://reviews.llvm.org/D42686

llvm-svn: 323786
2018-01-30 16:49:06 +00:00
Sergey Dmitriev b305d26b57 [OpenMP] libomptarget: move debugging dumps under control of env var LIBOMPTARGET_DEBUG
Disable default debugging dumps for libomptarget and plugins and move dumps
under control of environment variable LIBOMPTARGET_DEBUG=<integer>. Dumps
are enabled when LIBOMPTARGET_DEBUG is set to a positive integer value.

Debugging dumps are available only in debug build; release build does not
support it.

Differential Revision: https://reviews.llvm.org/D33227

llvm-svn: 310841
2017-08-14 15:09:59 +00:00
George Rokos 1546d31924 [OpenMP] Changes in the plugin interface
This patch chagnes the plugin interface so that:
1) future plugins can take advantage of systems with shared CPU/device storage
2) instead of using base addresses, target regions are launched by providing target addresseds and base offsets explicitly.

Differential revision: https://reviews.llvm.org/D33028
 

llvm-svn: 302663
2017-05-10 14:12:36 +00:00
George Rokos c13df8e5e0 [OpenMP] Optimized default kernel launch parameters in CUDA plugin
Differential Revision: https://reviews.llvm.org/D32321

llvm-svn: 301321
2017-04-25 16:34:13 +00:00
George Rokos 01954092d0 [OpenMP] CUDA plugin: More descriptive error messages
Differential Revision: https://reviews.llvm.org/D31206

llvm-svn: 298527
2017-03-22 17:36:22 +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