Delay `Precision.convert_module` until `configure_model` has run

[carmocca]

What does this PR do?

Fixes #18936

The main change is in src/lightning/pytorch/strategies/strategy.py. Everything else is a bit of flattening and making it as consistent as possible with its subclasses.

The half precision test is redundant. It wasn't failing before this PR. The relevant tests are the TransformerEngine and Bitsandbytes ones.

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:books: Documentation preview :books:: https://pytorch-lightning--19061.org.readthedocs.build/en/19061/

cc @carmocca @justusschock @awaelchli

[github-actions[bot]]

⚡ Required checks status: All passing 🟢

Groups summary

🟢 pytorch_lightning: Tests workflow

Check ID	Status
pl-cpu (macOS-11, lightning, 3.8, 1.13, oldest)	success	✅
pl-cpu (macOS-11, lightning, 3.10, 1.13)	success	✅
pl-cpu (macOS-11, lightning, 3.10, 2.1)	success	✅
pl-cpu (ubuntu-20.04, lightning, 3.8, 1.13, oldest)	success	✅
pl-cpu (ubuntu-20.04, lightning, 3.10, 1.13)	success	✅
pl-cpu (ubuntu-20.04, lightning, 3.10, 2.1)	success	✅
pl-cpu (windows-2022, lightning, 3.8, 1.13, oldest)	success	✅
pl-cpu (windows-2022, lightning, 3.10, 1.13)	success	✅
pl-cpu (windows-2022, lightning, 3.10, 2.1)	success	✅
pl-cpu (macOS-11, pytorch, 3.8, 1.13)	success	✅
pl-cpu (ubuntu-20.04, pytorch, 3.8, 1.13)	success	✅
pl-cpu (windows-2022, pytorch, 3.8, 1.13)	success	✅
pl-cpu (macOS-12, pytorch, 3.11, 2.0)	success	✅
pl-cpu (macOS-12, pytorch, 3.11, 2.1)	success	✅
pl-cpu (ubuntu-22.04, pytorch, 3.11, 2.0)	success	✅
pl-cpu (ubuntu-22.04, pytorch, 3.11, 2.1)	success	✅
pl-cpu (windows-2022, pytorch, 3.11, 2.0)	success	✅
pl-cpu (windows-2022, pytorch, 3.11, 2.1)	success	✅

These checks are required after the changes to src/lightning/pytorch/strategies/ddp.py, src/lightning/pytorch/strategies/deepspeed.py, src/lightning/pytorch/strategies/fsdp.py, src/lightning/pytorch/strategies/single_device.py, src/lightning/pytorch/strategies/single_xla.py, src/lightning/pytorch/strategies/strategy.py, src/lightning/pytorch/strategies/xla.py, tests/tests_pytorch/plugins/precision/test_bitsandbytes.py, tests/tests_pytorch/plugins/precision/test_half.py, tests/tests_pytorch/plugins/precision/test_transformer_engine.py.

🟢 pytorch_lightning: Azure GPU

Check ID	Status
pytorch-lightning (GPUs) (testing Lightning | latest)	success	✅
pytorch-lightning (GPUs) (testing PyTorch | latest)	success	✅

These checks are required after the changes to src/lightning/pytorch/strategies/ddp.py, src/lightning/pytorch/strategies/deepspeed.py, src/lightning/pytorch/strategies/fsdp.py, src/lightning/pytorch/strategies/single_device.py, src/lightning/pytorch/strategies/single_xla.py, src/lightning/pytorch/strategies/strategy.py, src/lightning/pytorch/strategies/xla.py, tests/tests_pytorch/plugins/precision/test_bitsandbytes.py, tests/tests_pytorch/plugins/precision/test_half.py, tests/tests_pytorch/plugins/precision/test_transformer_engine.py.

🟢 pytorch_lightning: Benchmarks

Check ID	Status
lightning.Benchmarks	success	✅

These checks are required after the changes to src/lightning/pytorch/strategies/ddp.py, src/lightning/pytorch/strategies/deepspeed.py, src/lightning/pytorch/strategies/fsdp.py, src/lightning/pytorch/strategies/single_device.py, src/lightning/pytorch/strategies/single_xla.py, src/lightning/pytorch/strategies/strategy.py, src/lightning/pytorch/strategies/xla.py.

🟢 pytorch_lightning: Docs

Check ID	Status
docs-make (pytorch, doctest)	success	✅
docs-make (pytorch, html)	success	✅

These checks are required after the changes to src/lightning/pytorch/strategies/ddp.py, src/lightning/pytorch/strategies/deepspeed.py, src/lightning/pytorch/strategies/fsdp.py, src/lightning/pytorch/strategies/single_device.py, src/lightning/pytorch/strategies/single_xla.py, src/lightning/pytorch/strategies/strategy.py, src/lightning/pytorch/strategies/xla.py.

🟢 mypy

Check ID	Status
mypy	success	✅

These checks are required after the changes to src/lightning/pytorch/strategies/ddp.py, src/lightning/pytorch/strategies/deepspeed.py, src/lightning/pytorch/strategies/fsdp.py, src/lightning/pytorch/strategies/single_device.py, src/lightning/pytorch/strategies/single_xla.py, src/lightning/pytorch/strategies/strategy.py, src/lightning/pytorch/strategies/xla.py.

🟢 install

Check ID	Status
install-pkg (ubuntu-22.04, app, 3.8)	success	✅
install-pkg (ubuntu-22.04, app, 3.11)	success	✅
install-pkg (ubuntu-22.04, fabric, 3.8)	success	✅
install-pkg (ubuntu-22.04, fabric, 3.11)	success	✅
install-pkg (ubuntu-22.04, pytorch, 3.8)	success	✅
install-pkg (ubuntu-22.04, pytorch, 3.11)	success	✅
install-pkg (ubuntu-22.04, lightning, 3.8)	success	✅
install-pkg (ubuntu-22.04, lightning, 3.11)	success	✅
install-pkg (ubuntu-22.04, notset, 3.8)	success	✅
install-pkg (ubuntu-22.04, notset, 3.11)	success	✅
install-pkg (macOS-12, app, 3.8)	success	✅
install-pkg (macOS-12, app, 3.11)	success	✅
install-pkg (macOS-12, fabric, 3.8)	success	✅
install-pkg (macOS-12, fabric, 3.11)	success	✅
install-pkg (macOS-12, pytorch, 3.8)	success	✅
install-pkg (macOS-12, pytorch, 3.11)	success	✅
install-pkg (macOS-12, lightning, 3.8)	success	✅
install-pkg (macOS-12, lightning, 3.11)	success	✅
install-pkg (macOS-12, notset, 3.8)	success	✅
install-pkg (macOS-12, notset, 3.11)	success	✅
install-pkg (windows-2022, app, 3.8)	success	✅
install-pkg (windows-2022, app, 3.11)	success	✅
install-pkg (windows-2022, fabric, 3.8)	success	✅
install-pkg (windows-2022, fabric, 3.11)	success	✅
install-pkg (windows-2022, pytorch, 3.8)	success	✅
install-pkg (windows-2022, pytorch, 3.11)	success	✅
install-pkg (windows-2022, lightning, 3.8)	success	✅
install-pkg (windows-2022, lightning, 3.11)	success	✅
install-pkg (windows-2022, notset, 3.8)	success	✅
install-pkg (windows-2022, notset, 3.11)	success	✅

These checks are required after the changes to src/lightning/pytorch/strategies/ddp.py, src/lightning/pytorch/strategies/deepspeed.py, src/lightning/pytorch/strategies/fsdp.py, src/lightning/pytorch/strategies/single_device.py, src/lightning/pytorch/strategies/single_xla.py, src/lightning/pytorch/strategies/strategy.py, src/lightning/pytorch/strategies/xla.py.

---

Thank you for your contribution! 💜

Note This comment is automatically generated and updates for 60 minutes every 180 seconds. If you have any other questions, contact carmocca for help.

[codecov[bot]]

Codecov Report

Merging #19061 (24a1b52) into master (c7c42dc) will decrease coverage by 33%. Report is 11 commits behind head on master. The diff coverage is 83%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #19061      +/-   ##
==========================================
- Coverage      82%      49%     -33%     
==========================================
  Files         448      440       -8     
  Lines       37915    37783     -132     
==========================================
- Hits        30985    18467   -12518     
- Misses       6930    19316   +12386     

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[carmocca]

The failing TPU job is for Fabric only, but Fabric isn't impacted by this PR so it must be an issue from somewhere else