On Jan 21, 2014, at 9:26 AM, John Baldwin <j...@freebsd.org> wrote: > On Monday, January 20, 2014 5:18:44 pm Alexander Kabaev wrote: >> On Mon, 20 Jan 2014 11:32:29 -0500 >> John Baldwin <j...@freebsd.org> wrote: >> >>> On Sunday 19 January 2014 18:18:03 Rui Paulo wrote: >>>> On 19 Jan 2014, at 17:59, Neel Natu <n...@freebsd.org> wrote: >>>>> Author: neel >>>>> Date: Mon Jan 20 01:59:35 2014 >>>>> New Revision: 260898 >>>>> URL: http://svnweb.freebsd.org/changeset/base/260898 >>>>> >>>>> Log: >>>>> Bump up WITNESS_COUNT from 1024 to 1536 so there are sufficient >>>>> entries for >>>>> WITNESS to actually work. >>>> >>>> This value should be automatically tuned... >>> >>> How do you propose to do so? This is the count of locks initialized >>> before witness' own SYSINIT is executed and the array it sizes is >>> allocated statically at compile time. This used to not be a static >>> array, but an intrusive list embedded in locks themselves, but we >>> decided to shave a pointer off of each lock that was only used for >>> that and to use a statically sized table instead. >>> >>> -- >>> John Baldwin >> >> As <CONSTANT1> + <CONSTANT2> * MAXCPU, as evidently most recent >> overflows reported were caused by jacking MAXCPU up from its default >> value? > > If raising MAXCPU changes the number of unique lock names used, then the > locks are named incorrectly. We don't use the 'pid' in the name for > PROC_LOCK precisely so that WITNESS will treat them all the same so > that if if it learns a lock order for pid 37 it enforces the same lock > order for pid 38. Device locks should follow a similar rule. They > should generally not include the device name (and in some cases they > really shouldn't even have the driver name).
Why shouldn’t they have a driver and device name? Wouldn’t it help identify possible deadlocks from driver instances calling into each other? Scott _______________________________________________ svn-src-head@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
