On Tue, Mar 03, 2020 at 11:23:39PM -0600, Eric W. Biederman wrote: > Al Viro <viro@xxxxxxxxxxxxxxxxxx> writes: > > > On Tue, Mar 03, 2020 at 05:48:31PM -0600, Eric W. Biederman wrote: > > > >> > I hope it gets serious beating, though - it touches pretty much every > >> > codepath in pathname resolution. Is there any way to sic the bots on > >> > a branch, short of "push it into -next and wait for screams"? > >> > >> Last I looked pushing a branch to kernel.org was enough for the > >> kbuild bots. Sending patches to LKML is also enough for those bots. > >> > >> I don't know if that kind of bot is what you need testing your code. > > > > Build bots are generally nice, but in this case... pretty much all of > > the changes are in fs/namei.c, which is not all that sensitive to > > config/architecture/whatnot. Sure, something like "is audit enabled?" > > may affect the build problems, but not much beyond that. > > > > What was that Intel-run(?) bot that posts "such-and-such metrics has > > 42% regression on such-and-such commit" from time to time? > > <checks> > > Subject: [locking/qspinlock] 7b6da71157: unixbench.score 8.4% improvement > > seems to be the latest of that sort, > > From: kernel test robot <rong.a.chen@xxxxxxxxx> > > > > Not sure how much of pathwalk-heavy loads is covered by profiling > > bots of that sort, unfortunately... ;-/ > > Do the xfs-tests cover that sort of thing? > The emphasis is stress testing the filesystem not the VFS but there is a > lot of overlap between the two. I do run xfstests. But "runs in KVM without visible slowdowns" != "won't cause them on 48-core bare metal". And this area (especially when it comes to RCU mode) can be, er, interesting in that respect. FWIW, I'm putting together some litmus tests for pathwalk semantics - one of the things I'd like to discuss at LSF; quite a few codepaths are simply not touched by anything in xfstests.
