[parrot/parrot] d351af: Fix a mailbox threads race, document another threa...

[GitHub]

  Branch: refs/heads/threads
  Home:   https://github.com/parrot/parrot
  Commit: d351afeabff9937414a16cedaab8d78bd5aba51b
      https://github.com/parrot/parrot/commit/d351afeabff9937414a16cedaab8d78bd5aba51b
  Author: Reini Urban <rurban at cpanel.net>
  Date:   2012-09-14 (Fri, 14 Sep 2012)

  Changed paths:
    M src/pmc/task.pmc

  Log Message:
  -----------
  Fix a mailbox threads race, document another threads race

The mailbox threads race was improved by suggestion of nine++.
TASK_recv_block_CLEAR(partner) writes concurrent with a read in !TASK_in_preempt_TEST(SELF).
To repro: m parrot && ~/bin/tsan-r4356-amd64-linux-self-contained.sh ./parrot t/pmc/task.t