Quoting Chris Wilson (2018-06-25 11:16:58) > Quoting Chris Wilson (2018-06-23 11:39:51) > > If we avoid cleaning up the old state immediately in > > intel_atomic_commit_tail() and defer it to a second task, we can avoid > > taking heavily contended locks when the caller is ready to procede. > > Subsequent modesets will wait for the cleanup operation (either directly > > via the ordered modeset wq or indirectly through the atomic helperr) > > which keeps the number of inflight cleanup tasks in check. > > > > As an example, during reset an immediate modeset is performed to disable > > the displays before the HW is reset, which must avoid struct_mutex to > > avoid recursion. Moving the cleanup to a separate task, defers acquiring > > the struct_mutex to after the GPU is running again, allowing it to > > complete. Even in a few patches time (optimist!) when we no longer > > require struct_mutex to unpin the framebuffers, it will still be good > > practice to minimise the number of contention points along reset. The > > mutex dependency still exists (as one modeset flushes the other), but in > > the short term it resolves the deadlock for simple reset cases. > > > > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > > This silences > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101600 > which is one of the *four* remaining failures in BAT. Acked-by: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> Maarten said he would ack it if I could dig up the bugzilla link for the CI fail. This is not the long term solution, just a convenient hack that adds a schedule point after the modeset (which in imo is beneficial). -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
