tree da965130018bdecf2030af1536af326d00923311
parent 20761453fb985d02cddf0f1b0566ae037195b52e
author Christopher Faulet <cfaulet@haproxy.com> 1532071913 +0200
committer Willy Tarreau <w@1wt.eu> 1532089481 +0200
encoding latin1

BUG/MEDIUM: threads: Fix the exit condition of the thread barrier

In thread_sync_barrier, we exit when all threads have set their own bit in the
barrier mask. It is done by comparing it to all_threads_mask. But we must not
use a simple equality to do so, becaue all_threads_mask may change. Since commit
ba86c6c25 ("MINOR: threads: Be sure to remove threads from all_threads_mask on
exit"), when a thread exit, its bit is removed from all_threads_mask. Instead,
we must use a bitwise AND to test is all bits of all_threads_mask are set.

This also requires that all_threads_mask is set to volatile if we want to
catch changes.

This patch must be backported in 1.8.