diff options
| author | Justus Winter <4winter@informatik.uni-hamburg.de> | 2014-12-15 11:53:26 +0100 |
|---|---|---|
| committer | Justus Winter <4winter@informatik.uni-hamburg.de> | 2015-02-17 20:29:15 +0100 |
| commit | fb8c531ddeef55c8581d3882bd1b1f501d980a30 (patch) | |
| tree | 58ad72469c5176a1bfaad978e9d56f591e26e115 /libports/manage-multithread.c | |
| parent | eceeaeb5a2d40875fd432148b9cf26b41497811d (diff) | |
libports: avoid acquiring global lock in message dispatch
* libports/interrupt-operation.c (ports_S_interrupt_operation): Update
`cancel_threshold' using atomic operations.
* libports/manage-multithread.c (internal_demuxer): Avoid taking the lock.
* libports/ports.h (struct port_info): Mention that one needs atomic
operations to access `cancel_threshold'.
Diffstat (limited to 'libports/manage-multithread.c')
| -rw-r--r-- | libports/manage-multithread.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/libports/manage-multithread.c b/libports/manage-multithread.c index ad22991c..58814d2e 100644 --- a/libports/manage-multithread.c +++ b/libports/manage-multithread.c @@ -178,10 +178,12 @@ ports_manage_port_operations_multithread (struct port_bucket *bucket, } else { - pthread_mutex_lock (&_ports_lock); - if (inp->msgh_seqno < pi->cancel_threshold) + mach_port_seqno_t cancel_threshold = + __atomic_load_n (&pi->cancel_threshold, __ATOMIC_SEQ_CST); + + if (inp->msgh_seqno < cancel_threshold) hurd_thread_cancel (link.thread); - pthread_mutex_unlock (&_ports_lock); + status = demuxer (inp, outheadp); ports_end_rpc (pi, &link); } |