2015-07-01 17:49 GMT-03:00 Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>: > On Wed, Jul 01, 2015 at 05:15:23PM -0300, Paulo Zanoni wrote: >> From: Paulo Zanoni <paulo.r.zanoni@xxxxxxxxx> >> >> Make sure we're not going to have weird races in really weird cases >> where a lot of different CRTCs are doing rendering and modesets at the >> same time. >> >> With this change and the stolen_lock from the previous patch, we can start >> removing the struct_mutex locking we have around FBC in the next patches. >> >> v2: >> - Rebase (6 months later) >> - Also lock debugfs and stolen. >> v3: >> - Don't lock a single value read (Chris). >> - Replace lockdep assertions with WARNs (Daniel). >> - Improve commit message. >> - Don't forget intel_pre_plane_update() locking. >> v4: >> - Don't remove struct_mutex at intel_pre_plane_update() (Chris). >> - Add comment regarding locking dependencies (Chris). >> - Rebase after the stolen code rework. >> - Rebase again after drm-intel-nightly changes. >> >> Signed-off-by: Paulo Zanoni <paulo.r.zanoni@xxxxxxxxx> > > Reviewed-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > > See below. > >> @@ -683,6 +721,8 @@ void intel_fbc_update(struct drm_device *dev) >> const struct drm_display_mode *adjusted_mode; >> unsigned int max_width, max_height; >> >> + WARN_ON(!mutex_is_locked(&dev_priv->fbc.lock)); >> + >> if (!HAS_FBC(dev)) >> return; > > This is now __intel_fbc_update() inside the fbc.lock. One would think > that the internal functions would only be called when FBC is desired. > > That looks to be true, except for the new intel_fbc_update(). You can > upgrade this to if (WARN_ON(!HAS_FBC(dev_priv))) return; after adding > the proper guard to intel_fbc_update(). __intel_fbc_update() is also called by intel_fbc_flush(). See "[PATCH 8/8] drm/i915: protect FBC functions with HAS_FBC checks" on the new series. I still have another series just with minor changes like this which I intend to send after the locking series. > -Chris > > -- > Chris Wilson, Intel Open Source Technology Centre -- Paulo Zanoni _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
