[Qemu-devel] [PATCH 0/2] rcu: support fork

[Paolo Bonzini]

Supporting fork in multithreaded programs is somewhat complicated,
however in QEMU we fork in two places (daemonize and smbd) and none of
them are complicated:

- daemonize happens before threads and mutexes proliferate unpredictably;
only the RCU state has to be reset and the call_rcu thread recreated

- smbd mostly does an exec in the child.

Unfortunately, glibc also makes forking terminally incompatible with
PTHREAD_MUTEX_ERRORCHECK, so you also need to disable that.

Paolo

Paolo Bonzini (2):
  qemu-thread: do not use PTHREAD_MUTEX_ERRORCHECK
  rcu: handle forks safely

 util/qemu-thread-posix.c |  6 +-----
 util/rcu.c               | 34 +++++++++++++++++++++++++++++++++-
 2 files changed, 34 insertions(+), 6 deletions(-)

-- 
2.3.0