On Sat, 2013-03-02 at 21:18 -0500, Rik van Riel wrote: > On 03/01/2013 11:32 PM, Michel Lespinasse wrote: > > > I think it may be nicer to take the rcu read lock at the call site > > rather than in ipc_obtain_object(), to make the rcu read lock/unlock > > sites pair up more nicely. Either that or make an inline > > ipc_release_object function that pairs up with ipc_obtain_object() and > > just does an rcu_read_unlock(). > > I started on a patch series to untangle the IPC locking, so > it will be a little more readable, and easier to maintain. > > It is a slower approach than Davidlohr's, as in, it will take > a little longer to put a patch series together, but I hope it > will be easier to debug... > > I hope to post a first iteration of the series by the middle > of next week.
Goody, I'll be watching out for it. I have a big box rt user who uses semaphores in their very tight constraint application. While they're using them carefully, I saw a trace where contention cost vs jitter budget was a bit too high for comfort, and semctl/semop collision. -Mike -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
