bitcoin/ci
Wladimir J. van der Laan 9996b1806a
Merge #21064: refactor: use std::shared_mutex & remove Boost Thread
060a2a64d4 ci: remove boost thread installation (fanquake)
06e1d7d81d build: don't build or use Boost Thread (fanquake)
7097add83c refactor: replace Boost shared_mutex with std shared_mutex in sigcache (fanquake)
8e55981ef8 refactor: replace Boost shared_mutex with std shared_mutex in cuckoocache tests (fanquake)

Pull request description:

  This replaces `boost::shared_mutex` and `boost::unique_lock` with [`std::shared_mutex`](https://en.cppreference.com/w/cpp/thread/shared_mutex) & [`std::unique_lock`](https://en.cppreference.com/w/cpp/thread/unique_lock).

  Even though [some concerns were raised](https://github.com/bitcoin/bitcoin/issues/16684#issuecomment-726214696) in #16684 with regard to `std::shared_mutex` being unsafe to use across some glibc versions, I still think this change is an improvement. As I mentioned in #21022, I also think trying to restrict standard library feature usage based on bugs in glibc is not only hard to do, but it's not currently clear exactly how we do that in practice (does it also extend to patching out use in our dependencies, should we be implementing more runtime checks for features we are using, when do we consider an affected glibc "old enough" not to worry about? etc). If you take a look through the [glibc bug tracker](https://sourceware.org/bugzilla/describecomponents.cgi?product=glibc) you'll no doubt find plenty of (active) bug reports for standard library code we already using. Obviously not to say we shouldn't try and avoid buggy code where possible.

  Two other points:

  [Cory mentioned in #21022](https://github.com/bitcoin/bitcoin/pull/21022#issuecomment-769274179):
  > It also seems reasonable to me to worry that boost hits the same underlying glibc bug, and we've just not happened to trigger the right conditions yet.

  Moving away from Boost to the standard library also removes the potential for differences related to Boosts configuration. Boost has multiple versions of `shared_mutex`, and what you end up using, and what it's backed by depends on:
  * The version of Boost.
  * The platform you're building for.
  * Which version of `BOOST_THREAD_VERSION` is defined: (2,3,4 or 5) default=2. (see [here](https://www.boost.org/doc/libs/1_70_0/doc/html/thread/build.html#thread.build.configuration) for some of the differences).
  * Is `BOOST_THREAD_V2_SHARED_MUTEX` defined? (not by default). If so, you might get the ["less performant, but more robust"](https://github.com/boostorg/thread/issues/230#issuecomment-475937761) version of `shared_mutex`.

  A lot of these factors are eliminated by our use of depends, but users will have varying configurations. It's also not inconceivable to think that a distro, or some package manager might start defining something like `BOOST_THREAD_VERSION=3`. Boost tried to change the default from 2 to 3 at one point.

  With this change, we no longer use Boost Thread, so this PR also removes it from depends, the build system, CI etc.

  Previous similar PRs were #19183 & #20922. The authors are included in the commits here.
  Also related to #21022 - pthread sanity checking.

ACKs for top commit:
  laanwj:
    Code review ACK 060a2a64d4
  vasild:
    ACK 060a2a64d4

Tree-SHA512: 572d14d8c9de20bc434511f20d3f431836393ff915b2fe9de5a47a02dca76805ad5c3fc4cceecb4cd43f3ba939a0508178c4e60e62abdbaaa6b3e8db20b75b03
2021-02-12 11:39:36 +01:00
..
lint rpc: Use RPCHelpMan for check-rpc-mappings linter 2021-01-28 08:16:34 +01:00
retry build: update retry to current version 2019-10-30 18:49:57 -04:00
test Merge #21064: refactor: use std::shared_mutex & remove Boost Thread 2021-02-12 11:39:36 +01:00
lint_run_all.sh scripted-diff: Bump copyright headers 2020-12-31 09:45:41 +01:00
README.md doc: move doc to ci readme 2020-06-19 10:44:00 -04:00
test_run_all.sh scripted-diff: Bump copyright headers 2020-12-31 09:45:41 +01:00

CI Scripts

This directory contains scripts for each build step in each build stage.

Running a Stage Locally

Be aware that the tests will be built and run in-place, so please run at your own risk. If the repository is not a fresh git clone, you might have to clean files from previous builds or test runs first.

The ci needs to perform various sysadmin tasks such as installing packages or writing to the user's home directory. While most of the actions are done inside a docker container, this is not possible for all. Thus, cache directories, such as the depends cache, previous release binaries, or ccache, are mounted as read-write into the docker container. While it should be fine to run the ci system locally on you development box, the ci scripts can generally be assumed to have received less review and testing compared to other parts of the codebase. If you want to keep the work tree clean, you might want to run the ci system in a virtual machine with a Linux operating system of your choice.

To allow for a wide range of tested environments, but also ensure reproducibility to some extent, the test stage requires docker to be installed. To install all requirements on Ubuntu, run

sudo apt install docker.io bash

To run the default test stage,

./ci/test_run_all.sh

To run the test stage with a specific configuration,

FILE_ENV="./ci/test/00_setup_env_arm.sh" ./ci/test_run_all.sh

Configurations

The test files (FILE_ENV) are constructed to test a wide range of configurations, rather than a single pass/fail. This helps to catch build failures and logic errors that present on platforms other than the ones the author has tested.

Some builders use the dependency-generator in ./depends, rather than using the system package manager to install build dependencies. This guarantees that the tester is using the same versions as the release builds, which also use ./depends.

If no FILE_ENV has been specified or values are left out, 00_setup_env.sh is used as the default configuration with fallback values.

It is also possible to force a specific configuration without modifying the file. For example,

MAKEJOBS="-j1" FILE_ENV="./ci/test/00_setup_env_arm.sh" ./ci/test_run_all.sh

The files starting with 0n (n greater than 0) are the scripts that are run in order.

Cache

In order to avoid rebuilding all dependencies for each build, the binaries are cached and re-used when possible. Changes in the dependency-generator will trigger cache-invalidation and rebuilds as necessary.