cb6b20e197
reader_permit::release_base_resources() is a soft evict for the permit:
it releases the resources aquired during admission. This is used in
cases where a single process owns multiple permits, creating a risk for
deadlock, like it is the case for repair. In this case,
release_base_resources() acts as a manual eviction mechanism to prevent
permits blockings each other from admission.
Recently we found a bad interaction between release_base_resources() and
permit eviction. Repair uses both mechanism: it marks its permits as
inactive and later it also uses release_base_resources(). This partice
might be worth reconsidering, but the fact remains that there is a bug
in the reader permit which causes the base resources to be released
twice when release_base_resources() is called on an already evicted
permit. This is incorrect and is fixed in this patch.
Improve release_base_resources():
* make _base_resources const
* move signal call into the if (_base_resources_consumed()) { }
* use reader_permit::impl::signal() instead of
reader_concurrency_semaphore::signal()
* all places where base resources are released now call
release_base_resources()
A reproducer unit test is added, which fails before and passes after the
fix.
Fixes: #28083
Closes scylladb/scylladb#28155
(cherry picked from commit b7bc48e7b7)
Closes scylladb/scylladb#28242
Scylla in-source tests.
For details on how to run the tests, see docs/dev/testing.md
Shared C++ utils, libraries are in lib/, for Python - pylib/
alternator - Python tests which connect to a single server and use the DynamoDB API unit, boost, raft - unit tests in C++ cqlpy - Python tests which connect to a single server and use CQL topology* - tests that set up clusters and add/remove nodes cql - approval tests that use CQL and pre-recorded output rest_api - tests for Scylla REST API Port 9000 scylla-gdb - tests for scylla-gdb.py helper script nodetool - tests for C++ implementation of nodetool
If you can use an existing folder, consider adding your test to it. New folders should be used for new large categories/subsystems, or when the test environment is significantly different from some existing suite, e.g. you plan to start scylladb with different configuration, and you intend to add many tests and would like them to reuse an existing Scylla cluster (clusters can be reused for tests within the same folder).
To add a new folder, create a new directory, and then
copy & edit its suite.ini.