Summary:
There was a race condition in the test where the rolling thread
acquired the mutex before the flush thread pinned the logger. Rather than add
more complicated synchronization to fix it, I followed Siying's suggestion to
use SyncPoint in the test code.
Comments in the LoadDependency() invocation explain the reason for each of the
sync points.
Test Plan:
Ran test 1000 times for tsan/asan. Will wait for all sandcastle tests
to finish before committing since this is a tricky test.
Reviewers: IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D54615
Summary:
For GetLogFileSize() and Flush(), they previously did not follow the
synchronization pattern for accessing logger_. This meant ResetLogger() could
cause logger_ destruction while the unsynchronized functions were accessing it,
causing a segfault.
Also made the mutex instance variable mutable so we can preserve
GetLogFileSize()'s const-ness.
Test Plan:
new test case, it's quite ugly because both threads need to access
one of the functions with SyncPoints (PosixLogger::Flush()), and also special
handling is needed to prevent the mutex and sync points from conflicting.
Reviewers: kradhakrishnan, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D54237
