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. We're almost green, so let's board up this window as well. -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
