Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/36606
This PR refactor the continuation logic of the async mode on autograd
engine, to avoid launch spinning works. To achieve that:
1. remove the continuation logic in
execute_graph_task_with_continuiation
2. separate the usage of execute_graph_task between dist_engine and
local engine, now dist_engine universally use
`execute_graph_task_until_ready_queue_empty` (a better name appreciated
here).
3. remove enqueue_blocked_task_on_cpu
4. remove the async mode in `execute_with_graph_task` as we don't need
to use it in dist_engine
Test Plan: Imported from OSS
Differential Revision: D21032731
Pulled By: wanchaol
fbshipit-source-id: 708ea3bc14815bdc151b56afa15eb85b4ac0f4b1
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/37061
This PR refactors:
1. `set_device` to make it out of Engine
2. put `graph_task_completed` into GraphTask
3. put `mark_graph_task_completed` into GraphTask
This also make the distributed engine easy to call those functions.
Test Plan: Imported from OSS
Differential Revision: D21188688
Pulled By: wanchaol
fbshipit-source-id: f56106e6ed7d966cfa4d962781c7865cc3c5321d
Summary:
# Goals
Do the following things during a distributed backward pass.
1. Accumulate the gradient of a variable to RPC context once the gradient is ready instead of at the very end of the backward pass.
2. Run post/pre hooks installed in`AccumulateGrad` nodes once the gradient is ready for the variable. Currently, the hooks in `AccumulateGrad` are not executed just because the function `AccumulateGrad` itself is not even evaluated by the local engine.
3. Make it extensible to support post hooks installed by DDP's reducer.
# Introduce GradCapturePreHook
## Why do we need this?
### Root issue:
* dist engine uses the autograd.grad-like API on the vanilla engine and then in the Future callback populates the context with the gradients. This is a bad emulation of the .backward() call on the vanilla engine.
### Practical issue:
* The leaf’s hook are not called (because associated with the AccumulateGrad that is not call in the autograd.grad-like API). Modules like DDP rely on these hooks.
* The Future is marked as completed before the context is actually populated with the grads leading to unexpected behavior on the user side.
* The Future callback is only called at the complete end of the backward and so too late for DDP if they want to overlap compute/transfert.
### Proposed solution:
* Provide hooks in the autograd.grad-like API that will allow the distributed engine to populate the context and call the hooks to better emulate the .backward call.
## Who can install a grad capture pre-hook?
This will be an internal hook at C++ level and it won’t be exposed to PyThon code. Only call-sites directly interacting with the local engine can install such hooks.
## Signature
The returned `grad` will be captured.
```
virtual const torch::Tensor& grad operator()(const torch::Tensor& grads) = 0;
```
## Where are hooks installed?
Grad capture pre-hooks are install in GraphTask::ExecInfo::Capture. ExecInfo is per node. Every backward run will have its own GraphTask instance.
## When/How will hooks be called?
When the local engine captures the grads for a node, all grad capture pre hooks are called one by one in the order they are added. The output grads of the hooks will replace the original grads.
The output of the last hook will be used for grad capturing.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/34501
Test Plan:
All existing tests should pass.
```
python setup.py develop
python test/distributed/rpc/test_dist_autograd_spawn.py DistAutogradTestWithSpawn.test_post_hooks
```
Differential Revision: D20953673
Pulled By: hczhu
fbshipit-source-id: 543b3844823330ea9f9856bab7c5cb2679290a53
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/36745
As we hold a mutex for our custom C++ Node, when calling reentrant
backward from custom C++ function, we will cocurrently holding many
mutexes up to MAX_DEPTH. TSAN only allow 65 mutexes at once, otherwise
it will complain. This PR lower the limit according to TSAN.
TSAN Reference: https://github.com/google/sanitizers/issues/950
Test Plan: Imported from OSS
Differential Revision: D21072604
Pulled By: wanchaol
fbshipit-source-id: 99cd1acab41a203d834fa4947f4e6f0ffd2e70f2
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/35101
TSAN is noting lock-order-inversion in context of dist autograd because
we're holding lock when GraphTask calls markCompleted() on the relevant futureResult_.
Add an atomic bool to make it possible to protect this without holding the mutex,
and also fix alignment of a few struct vars.
ghstack-source-id: 101805283
Test Plan: buck test mode/opt-tsan //caffe2/test/distributed/rpc:dist_autograd_spawn_thrift
Differential Revision: D20553517
fbshipit-source-id: 446e3718dd68876bd312166ecceed1d92868ce4e
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/35523
In this PR we extend ThreadLocalState to cover dispatch keys and
ThreadLocalDebugInfo and move it from JIT interpreter down to
thread management (at::launch) and autograd (backward threads) code
Test Plan: unit tests (CI)
Reviewed By: dzhulgakov
Differential Revision: D20615714
fbshipit-source-id: 16a9fc96a25cb6c2629230b1187fbf78786ac565
Summary: This diff fixes the issues with current handling of debug information passed along the execution of the model. (For example, it is possible that multiple calls to the debug guard may override each other)
Test Plan: CI test/cpp/jit
Reviewed By: dzhulgakov
Differential Revision: D20602775
fbshipit-source-id: 4683957954028af81a1a0f1f12b243650230c9bb
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/33157
This PR enables graph level thread parallelism on CPU for the Autograd
Engine. It replace https://github.com/pytorch/pytorch/pull/29574 for the
reason of task level parallelism drawbacks with the existing autograd
system.
Fixes https://github.com/pytorch/pytorch/issues/18333
The graph level parallelism on CPU design:
1. Remove the single CPU thread that init in the Engine itself and allow
the owning thread (which calls Engine::execute) to drive the Engine
execution so that we could let outer threading to enable thread
parallelism.
2. Maintain a separate ReadyQueue per CPU thread, and stash the
ReadyQueue for different devices/threads into the thread local
shared_ptr, the Engine itself will memorize the shared_ptr of the
ReadyQueue to different devices (other than CPU)
3. The CPU thread local ReadyQueue is initialized per CPU thread
Engine::execute call (or `backward()`, `grad()` call), and memorized
the shared_ptr into the GraphTask since every `backward()` call have
its own GraphTask
4. Cross device NodeTask push is accomplished by 2 and 3. we can refer
to device's ReadyQueue from Engine, and CPU's ReadyQueue from
GraphTask, which means if we can push to a different ReadyQueue
according to the device
5. Termination of the CPU thread: if we mark the graph_task as
completed, we will exit the while loop and terminate the current
backward execution, because it's guranteed that all other NodeTasks
is finished before we mark a GraphTask as complete
6. re-entrant thread logic keeps the same, reentrant thread detection is
similar as before, we set the worker_device to NO_DEVICE initially
and set to CPU afterward to detect if this is a reentrant call or not.
7. we still have the reentrant thread pool that create new threads if it's
a deep reentrant case, and reuse the ReadyQueue with the parent thread
for performance.
Since we introduce the thread parallelism on CPU, we have to ensure the
thread safety of the GraphTask. This is not a problem if we execute all
forward in different threads since we will build separate GraphTask in
different threads, and each GraphTask is a separate instance that share
nothing, i.e. Hogwild training on CPU should be fine on this case.
But there might be case that user would like to do some part of the task in
a single thread, and do the rest of work in several threads
concurrently, so thread safety is crucial in those cases. The thread
safety strategy for the multithread autograd is as follows:
1. Add a mutex to protect thread safety in Autograd Node/Function, and
hold the lock for different data racing cases
2. Lock the mutex during Node::apply(), this is to ensure Node that
writing to the shared variable are not racing across threads (i.e.
AccumulateGrad and custom C++ Autograd Node if writing to shared
variables )
3. Lock the mutex during Node::release_variables(), this serve the
purpose that when we release saved_variables from one thread, no
other threads can call the Node::apply(), this ensures the variable
references from other threads aren't dangling.
4. If we don't release any variables and no shared data read/write in
the Node i.e. purely functional, we don't lock the mutex
This way we could protect the thread safety on Autograd Node, but we
could still not protect the thread safety on Node pre/post C++ hooks
(python hooks are automatically thread safe), we rely on the user to
write thread safe C++ hooks if they want the hook to be correctly
applied in multithreading environment.
**User visiable changes**:
There're not too much user visiable changes, since we use the owning
thread to drive the autograd execution, user could write their own
threading code and does not block on the Autograd engine, some behaviors
that user should be aware of:
**Non-determinism**:
if we are calling backward() on multiple thread concurrently but with
shared inputs (i.e. Hogwild CPU training). Since parameters are automatically shared across threads, gradient accumulation might become non-deterministic on backward calls across threads, because two backward calls might access and try to accumulate the same .grad attribute. This is technically not safe, and it might result in racing condition and the result might be invalid to use.
But this is expected pattern if user are using the multithreading
approach to drive the whole training process but using shared
parameters, user who use multithreading should have the threading model
in mind and should expect this to happen. User should use the functional
interface `torch.autograd.grad()` to calculate the gradients instead of
`backward()` on loss.
**Graph retaining**:
If part of the autograd graph is shared between threads, i.e. run first
part of forward single thread, then run second part in multiple threads,
then the first part of graph is shared. In this case different threads execute grad() or backward() on the same graph might
have issue of destroying the graph on the fly of one thread, and the
other thread will crash in this case. We will error out to the user
similar to what call `backward()` twice with out `retain_graph=True`, and let the user know they should use `retain_graph=True`.
**TODOs**:
[ ] benchmark the PR with example models and datasets to demonstrate
the performance gain in CPU training
[ ] ensure that we don't regress the single thread autograd performance
**Follow ups**:
[ ] a correct and tight integration with distributed autograd
[ ] try to unify the thread pool between JIT and Autograd, and see if
there's unifying pattern that we could apply universally
Test Plan: Imported from OSS
Differential Revision: D20236771
Pulled By: wanchaol
fbshipit-source-id: 1e0bd4eec14ffebeffdb60b763b8d6f0e427eb64
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/35066Closes#24965
Prior to this commit, final_callbacks_ are cleared on exit of ANY
backward. When using reentrant backward, the last backward would
remove all callbacks from the engine. However, this might lead to
unexpected behavior. For example, the application could install
a final callback after forward, and expecting this callback to fire
when all gradients are ready. If there is a renentrant backward on
a subgraph, it would fire the callback and delete it on exit,
meaning that when fired, not all gradients are ready.
**Failed Attempt**
The 1st attempt was trying to move the callback to the GraphTask
in engine::execute(). However, this failed because more callbacks
could be installed during backward pass.
**Current Solution**
Final callbacks are stored as a member variable in the GraphTask.
* Insertion: use the thread_local current_graph_task to find the
target GraphTask, and append final callback.
* Deletion: final callbacks have the same lifetime as a GraphTask
* Execution: Use the GraphTask provided in the argument to find
final callbacks.
Test Plan: Imported from OSS
Differential Revision: D20546474
Pulled By: mrshenli
fbshipit-source-id: d3f3449bb5af9f8703bcae63e6b52056cd535f11
Summary:
Because `this` must be valid while `Engine::main_thread` is running, at least for non-reentrant worker threads
Pull Request resolved: https://github.com/pytorch/pytorch/pull/34529
Test Plan: Run `test_api --gtest-filter=ModulesTest.InstanceNorm1d` in a loop
Differential Revision: D20552717
Pulled By: malfet
fbshipit-source-id: a0197671db1b7b1499dda675e43e0826f368bf0d
Summary:
Make sure that there could not be more than one instance of either `torch::autograd::Engine` or `torch::autograd::python::PythonEngine`
Pull Request resolved: https://github.com/pytorch/pytorch/pull/34567
Test Plan: CI
Differential Revision: D20390622
Pulled By: malfet
fbshipit-source-id: c90595032afc88f552dee52901361b58b282dc1a
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/33214
Distributed autograd had some custom logic in terms of how we
accumulated gradients. This was mostly done early on to enable basic
functionality. Although, in the long term we should merge this logic with what
we have in the local autograd engine. A lot of work has gone into ensuring we
accumulate grads correctly and efficiently and we should reuse that as a
starting point.
We can investigate if we need further custom logic for distributed autograd
later on if we need additional optimizations.
In this PR I've merged the gradient accumulation logic and also the gradient
hooks. As a result, now gradient hooks are called in distributed autograd as
well.
ghstack-source-id: 99838019
Test Plan: waitforbuildbot
Differential Revision: D19843284
fbshipit-source-id: 7923d7e871fb6afd3e98dba7de96606264dcb5f3
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/33885Fixes: #32835Fixes: #5834
Can not combine with CUDA's implementation as each of them requires individual `std::once_flag` as well as different `forked_autograd_child` functions. CUDA version relays to python module, autograd uses TORCH_CHECK to report error to python and cpp.
Test Plan: Imported from OSS
Differential Revision: D20144024
Pulled By: VitalyFedyunin
fbshipit-source-id: e7cf30568fff5110e9df7fe5b23f18ed992fa17f
Summary:
Just update the comment to make it accurate.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/32222
Differential Revision: D19410428
Pulled By: albanD
fbshipit-source-id: ad13596382613c2728e674a47049ea4f563964b9
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/31230
A major issue with distributed autograd currently is that we block an
RPC thread when we call Engine::execute_with_graph_task.
To resolve this issue, I've made modifications to the local autograd engine
such that `execute_with_graph_task` returns a Future instead. The `execute()`
methods for Engine::execute() and DistEngine::execute() still wait() on this
Future which ensures there is no change in behavior yet.
In follow up PRs we can modify the distributed autograd engine to take
advantage of this Future.
Closes#26359
ghstack-source-id: 96298057
Test Plan: waitforbuildbot
Differential Revision: D18999709
fbshipit-source-id: 388f54467fd2415a0acb7df17bd063aedc105229
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/30642
Adding a couple of basic metrics for distributed autograd which would
help in determining stuckness.
ghstack-source-id: 95156189
Test Plan: waitforbuildbot
Differential Revision: D18776478
fbshipit-source-id: a0556ad6fe2b7c3cd0082ee2350c1c78cafaaec5
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/29041
1) Enhanced autograd unit tests to test the
torch.distributed.autograd.backward() API more thoroughly on Python UDFs.
2) Enhanced `python_error` to override `what` such that it returns an
appropriate error string if we call `what()` on this error. This ensures we can
propagate exceptions over the wire during RPCs (since we get the error string
by calling what() on the exception)
ghstack-source-id: 93098679
ghstack-source-id: 93098679
Test Plan: waitforbuildbot
Reviewed By: mrshenli
Differential Revision: D18273041
fbshipit-source-id: 85d3932fed6337668a812367fdfce233c1b3ff8e
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/28824
1) Enhanced autograd unit tests to test the
torch.distributed.autograd.backward() API more thoroughly on Python UDFs.
2) Enhanced `python_error` to override `what` such that it returns an
appropriate error string if we call `what()` on this error. This ensures we can
propagate exceptions over the wire during RPCs (since we get the error string
by calling what() on the exception)
ghstack-source-id: 92972494
Test Plan: waitforbuildbot
Differential Revision: D18195584
fbshipit-source-id: b795daf644ba1816fdec484545192ab55a2f71e7
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/27940
1) If we receive an error for outstanding rpcs, we enqueue an appropriate error
on the local autograd engine.
2) Add an `exit_on_error` mode for the local autograd engine, where the
computation stops if we see an error.
ghstack-source-id: 92603377
Test Plan: Added unit tests to test failures.
Differential Revision: D17916844
fbshipit-source-id: 199a7832f1033c36a9bbcc1e80d86576c04965d0
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/27022
This change implements the "FAST" mode distributed autograd backward
pass as described in https://github.com/pytorch/pytorch/issues/23110.
At a high level the backward pass works as follows:
1. We start by computing dependencies on the node that calls
`torch.distributed.backward`.
2. This node computes the dependencies starting from the root nodes provided in
the backward call and all the 'send' functions present in the current autograd
context. The "FAST" mode assumes all 'send' functions are part of the autograd
computation.
3. Once the dependency computation is done, the distributed autograd engine
calls the local autograd engine to execute the autograd graph. Note that the
autograd graph on a single node is not necessarily connected because of
inter-node communication. As a result, we have special handling to ensure the
local autograd engine ensures we execute the entire graph starting from the
provided roots and all 'send' functions on the node.
4. When the local autograd engine hits a 'recv' function, it performs an async
RPC to send the gradients over to the appropriate node and stores a future in
the autograd context to keep track of this RPC.
5. On the destination node, the appropriate 'send' function is looked up and
enqueued on the local autograd engine. If this is the first time the node is
hearing about this autograd context id on the backward pass, then the node
computes dependencies for the local autograd engine.
6. As part of compute dependencies, the distributed autograd engine discovers
all leaf nodes and ensures those are passed as 'outputs' to the local autograd
engine. This avoids running the 'AccumulateGrad' function.
7. The gradients computed for the leaf nodes are then actually accumulated in
`DistAutogradContext` for the appropriate autograd context id.
8. The distributed autograd engine waits for the local autograd engine
to complete and also waits for all the 'Futures' (stored in 4.) for respective
RPCs to finish.
We have made the following changes to the local autograd engine for this
purpose:
1. Expose GraphTask and NodeTask so that the distributed autograd engine can
use them.
2. Expose a `execute_with_graph_task` API which gives the distributed engine
to build a GraphTask and pass it to the local autograd engine.
3. Expose a `enqueue_on_cpu` API, which allows the distributed engine to build
a `NodeTask` for a 'send' function and enqueue it on the local autograd engine.
In addition to this a few general improvements:
1. Added a `PropagateGradients` RPC call for the 'recv' function to pass
gradients to the appropriate node during the backward pass.
2. Use IValues as much as possible in serialization for RpcWithAutograd.
3. If Future.wait(), contains a message type EXCEPTION, we throw an appropriate
exception instead of just returning the message. This is inline with what most
Future.wait() APIs do.
4. Added a `get_gradients(context_id)` API which allows users to retrieve a map
from Tensor to respective gradient for the provided context_id on the local
node.
ghstack-source-id: 91794926
Test Plan: unit tests.
Differential Revision: D17652615
fbshipit-source-id: 96f65c52adb2706ee29f4b49e1655afaa0a3bec3
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/22397
Test Plan:
Added test for reentrant backwards with checkpoint and a test for a recursive backwards function (which should fail if we run all the reentrant tasks recursively in the same thread) and for testing priority of reentrant tasks.
~~Will add a test for priority of reentrant tasks in future pr.~~
Imported from OSS
Differential Revision: D16131955
fbshipit-source-id: 18301d45c1ec9fbeb566b1016dbaf7a84a09c7ac
Summary:
Anywhere we used #include "foo.h", we now say #include <foo.h>
Paths are adjusted to be rooted out of aten/src, torch/lib, or
the root level directory.
I modified CMakeLists.txt by hand to remove TH and THC from
the include paths.
I used the following script to do the canonicalization:
```
import subprocess
import re
import os.path
files = subprocess.check_output(['git', 'ls-files']).decode('utf-8').rstrip().split('\n')
for fn in files:
if not any(fn.endswith(suff) for suff in ['.cu', '.cpp', '.in', '.h', '.hpp', '.cu', '.cuh', '.cc']):
continue
if not any(fn.startswith(pref) for pref in ["aten/", "torch/"]):
continue
with open(fn, 'r') as f:
c = f.read()
def fmt(p):
return "#include <{}>".format(p)
def repl(m):
p = m.group(1)
if p in ["dlfcn.h", "unistd.h", "nvrtc.h", "cuda.h", "cuda_runtime.h", "cstdint", "cudnn.h", "Python.h", "cusparse.h", "cuda_runtime_api.h", "cuda_fp16.h", "cublas_v2.h", "stdint.h", "curand_kernel.h"]:
return fmt(p)
if any(p.startswith(pref) for pref in ["torch/csrc", "c10/", "ATen/", "caffe2/", "TH/", "THC/", "Eigen/", "gtest/", "zdl/", "gloo/", "onnx/", "miopen/"]):
return fmt(p)
for root in ["aten/src", "torch/lib", ""]:
for bad_root in [os.path.dirname(fn), "aten/src/TH", "aten/src/THC", "torch/csrc"]:
new_p = os.path.relpath(os.path.join(bad_root, p), root)
if not new_p.startswith("../") and (os.path.exists(os.path.join(root, new_p)) or os.path.exists(os.path.join(root, new_p + ".in"))):
return fmt(new_p)
print("ERROR: ", fn, p)
return m.group(0)
new_c = re.sub(r'#include "([^"]+)"', repl, c)
if new_c != c:
print(fn)
with open(fn, 'w') as f:
f.write(new_c)
```
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/14849
Reviewed By: dzhulgakov
Differential Revision: D13363445
Pulled By: ezyang
fbshipit-source-id: 52361f878a672785f9306c9e9ab2513128092b68
Summary:
Linting `torch/csrc/` (non-recursive) and `torch/csrc/autograd` (non-recursive).
Fixed things like:
- `typedef` vs `using`
- Use `.empty()` instead of comparing with empty string/using `.size() == 0`
- Use range for loops instead of old style loops (`modernize-`)
- Remove some `virtual` + `override`
- Replace `stdint.h` with `cstdint`
- Replace `return Type(x, y)` with `return {x, y}`
- Use boolean values (`true`/`false`) instead of numbers (1/0)
- More ...
ezyang apaszke cpuhrsch
Pull Request resolved: https://github.com/pytorch/pytorch/pull/11050
Differential Revision: D9597505
Pulled By: goldsborough
fbshipit-source-id: cb0fb4793ade885a8dbf4b10484487b84c64c7f2
Summary:
More clang tidy cleanups in `torch/csrc`. This time:
1. `hicpp-use-equals-default` recommends `= default` instead of `{}` for constructors/destructors. This is better practice because it expresses the intent better (https://stackoverflow.com/questions/6502828/what-does-default-mean-after-a-class-function-declaration)
2. `readability-inconsistent-declaration-parameter-name` enforces that parameter names in the declaration match parameter names in the definition. This is just generally useful and can prevent confusion and bugs.
Also updated my script a little bit.
apaszke ezyang
Pull Request resolved: https://github.com/pytorch/pytorch/pull/9737
Differential Revision: D9069069
Pulled By: goldsborough
fbshipit-source-id: f7b3f3a4eb4c9fadc30425a153566d3b613a41ae
* Factor python dependency out of interpreter
* Remove NO_PYTHON for the autograd engine
If there is no python bindings, then a default Engine is constructed
the first time it is requested.
If the python libraries are loaded, then they override the default
accessor and the default engine becomes a python Engine.
Note: it is possible for two engines to be generated if a non-python
one gets created before the python bindings are loaded. This case
is rare, and just results in additional threads being spawned.
* Fixing AlexNet test which is skipped in CI
* Add backward() to Tensor and Variable
* Add at:: in front of Tensor
* Trying to not move optional to appease windows?
* Move implementation into cpp file
* Undo some formatting changes
* Autograd container for trading compute for memory
* add a unit test for checkpoint
* address comments
* address review comments
* adding some docs for the checkpoint api
* more comments
* more comments
* repro bug
* Fix a subtle bug/apply some review comments
* Update checkpoint.py
* Run everything in grad mode
* fix flake and chunk=1
* use imperative backward as per discussion
* remove Variable and also add models and test for models
* Add a simple thread local variable to check for autograd grad mode
* remove models and models test after debugging
* address review comments
* address more comments
* address more comments
This PR adds the possibility to build the C++ parts of autograd and jit, with no dependency on Python.
The goal is to allow taking a PyTorch IR representation (a tree s-expr) and running it with provided inputs.
Prerequisite: build PyTorch so that codegen runs once.
Instructions:
cd tools/cpp_build
bash build_all.sh
This will build libtorchjit and torchjit_test in tools/cpp_build/build/torchjit-build. The latter basically runs the code in test_jit.cpp for now.
While writing the PR, it turned out that a few of Python.h includes were redundant. They were removed here (PyTorch tests still pass on my machine, we'll see CI).
* Introduce Python-free builds of autograd and jit
* Remove NO_PYTHON ifdef in functions/special
* Improve Function interface
* Undo tracer changes
* Fix bug in VariableType.set_history
* Rename function_counter and sequence_number to sequence_nr
* Clarify Function documentation
* Replace swap_next_edges with next_edges() getter
* Bring back set_gradient_edge
* Simplify special.cpp
* add_gradient_edge -> create_gradient_edge
* Add mutable getters for pre/post hooks
* Use make_variable with Edge
* Remove remove_gradient_edge in favor of detach_
* Fix documentation and remove create_gradient_edge friend method
* Canonicalize some includes
Previously the side-effect free grad calculation was performed
using callbacks that could also override the decision to run a
function. However this had a few problems e.g. it forced us to iterate
over pretty much all functions in the graph and drop their buffers.
This patch improves the mechanism, by adding explicit support for this
kind of evaluation in execute(). It's safer, and the algorithm used to
decide which nodes have to be evaluated was replaced with a faster one.
This removes volatile from Variable. The functionality is mostly
replaced by a global (thread-local) flag, which is controlled by
torch.set_grad_enabled() and the context manager torch.no_grad().
In C++, the flag is exposed through GradMode::is_enabled() and GradMode::set_enabled()
Fixes#3627
Primary things I had to fix:
- Suppress _XOPEN_SOURCE warnings by ensuring that Python.h is included
first, because it always unconditionally defines this macro.
- Turn off strict aliasing, because Python 2 doesn't work with strict
aliasing.
- Workaround setuptools bug, where it's incorrectly passing
-Wstrict-prototypes to C++ compilers (where this doesn't make
any sense)
To compile csrc with -Werror, run `CFLAGS="-Werror" python setup.py build_ext`
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
The core autograd Variable, Function, and Engine no longer depend on the
Python API. This let's us implement functions in C++. In the future, we
can also multithread engine and release the GIL for most of the
non-Python backwards.
