On Wed, Jan 22, 2025 at 08:42:49PM +1100, Dave Chinner wrote: > On Tue, Jan 21, 2025 at 11:05:20PM -0800, Darrick J. Wong wrote: > > On Wed, Jan 22, 2025 at 05:08:17PM +1100, Dave Chinner wrote: > > > On Tue, Jan 21, 2025 at 08:24:00PM -0800, Darrick J. Wong wrote: > > > > On Tue, Jan 21, 2025 at 02:28:26PM +1100, Dave Chinner wrote: > > > > > On Thu, Jan 16, 2025 at 03:27:15PM -0800, Darrick J. Wong wrote: > > > > > > c) Putting test subprocesses in a systemd sub-scope and telling systemd > > > > > > to kill the sub-scope could work because ./check can already use it to > > > > > > ensure that all child processes of a test are killed. However, this is > > > > > > an *optional* feature, which means that we'd have to require systemd. > > > > > > > > > > ... requiring systemd was somewhat of a show-stopper for testing > > > > > older distros. > > > > > > > > Isn't RHEL7 the oldest one at this point? And it does systemd. At this > > > > point the only reason I didn't go full systemd is out of consideration > > > > for Devuan, since they probably need QA. > > > > > > I have no idea what is out there in distro land vs what fstests > > > "supports". All I know is that there are distros out there that > > > don't use systemd. > > > > > > It feels like poor form to prevent generic filesystem QA > > > infrastructure from running on those distros by making an avoidable > > > choice to tie the infrastructure exclusively to systemd-based > > > functionality.... > > > > Agreed, though at some point after these bugfixes are merged I'll see if > > I can build on the existing "if you have systemd then ___ else here's > > your shabby opencoded version" logic in fstests to isolate the ./checks > > from each other a little better. It'd be kinda nice if we could > > actually just put them in something resembling a modernish container, > > albeit with the same underlying fs. > > Agreed, but I don't think we need to depend on systemd for that, > either. > > > <shrug> Anyone else interested in that? > > check-parallel has already started down that road with the > mount namespace isolation it uses for the runner tasks via > src/nsexec.c. > > My plan has been to factor more of the check test running code > (similar to what I did with the test list parsing) so that the > check-parallel can iterate sections itself and runners can execute > individual tests directly, rather than bouncing them through check > to execute a set of tests serially. Then check-parallel could do > whatever it needed to isolate individual tests from each other and > nothing in check would need to change. > > Now I'm wondering if I can just run each runner's check instance > in it's own private PID namespace as easily as I'm running them in > their own private mount namespace... > > Hmmm - looks like src/nsexec.c can create new PID namespaces via > the "-p" option. I haven't used that before - I wonder if that's a > better solution that using per-test session IDs to solve the pkill > --parent problem? Something to look into in the morning.... I tried that -- it appears to work, but then: # ./src/nsexec -p bash Current time: Wed Jan 22 13:43:33 PST 2025; Terminal: /dev/pts/0 # ps fatal library error, lookup self # Regular processes and pkill/pgrep seem to work, but that didn't seem especially encouraging so I stopped. :/ --D > -Dave. > > -- > Dave Chinner > david@xxxxxxxxxxxxx >
