On Monday, February 09, 2015 07:19:45 PM Randall Stewart wrote: > Author: rrs > Date: Mon Feb 9 19:19:44 2015 > New Revision: 278469 > URL: https://svnweb.freebsd.org/changeset/base/278469 > > Log: > This fixes two conditions that can incur when migration > is being done in the callout code and harmonizes the macro > use.: > 1) The callout_active() will lie. Basically if a migration > is occuring and the callout is about to expire and the > migration has been deferred, the callout_active will no > longer return true until after the migration. This confuses > and breaks callers that are doing callout_init(&c, 1); such > as TCP. > 2) The migration code had a bug in it where when migrating, if > a two calls to callout_reset came in and they both collided with > the callout on the wheel about to run, then the second call to > callout_reset would corrupt the list the callout wheel uses > putting the callout thread into a endless loop. > 3) Per imp, I have fixed all the macro occurance in the code that > were for the most part being ignored. > > Phabricator D1711 and looked at by lstewart and jhb and sbruno. > Reviewed by: kostikbel, imp, adrian, hselasky > MFC after: 3 days > Sponsored by: Netflix Inc.
Thank you guys for working together to fix the migration race in a way that lets CALLOUT_MPSAFE timers use multiple CPUs still. I do think that callout_drain_async() would also be useful to add. -- John Baldwin _______________________________________________ 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"
