On Saturday, March 23, 2013 11:11:20 pm Eric van Gyzen wrote: > At work, we discovered that our application's IPMI thread would often > use a lot of CPU time. The KCS thread uses DELAY to wait for the BMC, > so it can run without sleeping for a "long" time with a slow BMC. It > also holds the ipmi_softc.ipmi_lock during this time. When using > adaptive mutexes, an application thread that wants to operate on the > ipmi_pending_requests list will also spin during this same time. > > We see no reason that the KCS thread needs to hold the lock while > servicing a request. We've been running with the attached patch for a > few months, with no ill effects.
The lock protects against concurrent access to the registers themselves (though the thread sort of does this already). However, even with a slow BMC it shouldn't be waiting but so long. I had some other comments about this patch in my reply to when it was committed. -- John Baldwin _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "[email protected]"
