tree 5b63a06d0107141dd9161334baca43ff671913e4
parent 595277850582341bead228ce84d411b423a8be35
author Abdullah Alamoudi <bamousaa@gmail.com> 1519105625 -0800
committer Michael Blow <mblow@apache.org> 1519150242 -0800

[NO ISSUE][STO] Fix deadlock in buffer cache

- user model changes: no
- storage format changes: no
- interface changes: no

details:
- When two threads concurrently attempt to pin a page,
  one as a new page, the other as an existing page, a deadlock
  might happen.
- The deadlock is caused by the reader as a new page setting the
  valid flag before the ReaderThread attempts to read the page.
- The fix is to have the reader thread ignore the read request
  and have the reader as a new page notify all the other readers
  that the page is valid.

Change-Id: I50cf18d96228a1ad78ce11f5258252e8d0107d86
Reviewed-on: https://asterix-gerrit.ics.uci.edu/2407
Integration-Tests: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Tested-by: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Contrib: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Reviewed-by: Michael Blow <mblow@apache.org>