The first patch in the composite runtime: blockpoints and a lock

gparmer commented 5 years ago

Summary of this Pull Request (PR)

Some support for block-point-based locks along with a simple test (crttest). This is a feature addition, and changes existing code very minimally, so I don't see much risk for existing applications. I want this to concretely start a more in-depth blockpoint discussion.

Limitations.

The lock is multi-core aware as are blockpoints, but the sl support is not. The stacklist needs modification to track blocked threads with trebor stacks. Update: Added a Treiber stack to track blocked threads. Now this should be multi-core aware.
I'm not sure if wakeups of blocked threads on other cores actually work right now. Still pending.

I believe this blockpoint API is stable. Next steps will be to

implement channels using this API, and
fix the multi-core support after I talk to @phanikishoreg and determine if sl supports cross-core wakeup.

Intent for your PR

Choose one (Mandatory):

[ ] This PR is for a code-review and is intended to get feedback, but not to be pulled yet.
[x] This PR is mature, and ready to be integrated into the repo.

Reviewers (Mandatory):

@WenyuanShao @phanikishoreg @hungry-foolish

Code Quality

As part of this pull request, I've considered the following:

Style:

[x] Comments adhere to the Style Guide (SG)
[x] Spacing adhere's to the SG
[x] Naming adhere's to the SG
[x] All other aspects of the SG are adhered to, or exceptions are justified in this pull request
[ ] I have run the auto formatter on my code before submitting this PR (see doc/auto_formatter.md for instructions)

Code Craftsmanship:

[x] I've made an attempt to remove all redundant code
[x] I've considered ways in which my changes might impact existing code, and cleaned it up
[x] I've formatted the code in an effort to make it easier to read (proper error handling, function use, etc...)
[x] I've commented appropriately where code is tricky
[x] I agree that there is no "throw-away" code, and that code in this PR is of high quality

Testing

I've tested the code using the following test programs (provide list here):

[x] micro_booter
[x] unit_pingpong
[x] unit_schedtests
[x] crttests

gparmer commented 5 years ago

Added a Treiber stack to track blocked threads. Now multicore-safe. Wakeups still don't go between cores, so that is the last thing to do. @phanikishoreg said he can do this.

gparmer commented 5 years ago

Added channels. Added tests to crttests.c. See crt_chan.h for the API and implementation. Quite simple.

@hungry-foolish @phanikishoreg

gparmer commented 4 years ago

This was meant for feedback. That was accomplished. Closing now.

gwsystems / composite