Am 07.09.2011 07:33, schrieb Stéphane Marchesin: > 2011/9/2 Jose Fonseca <jfons...@vmware.com>: >> ----- Original Message ----- >>> Hi, >>> >>> While debugging some code I ran across the following situation: >>> >>> - pipe_context c1 is created >>> - pipe_surface s1 is created >>> - strb-> surface is set to s1 (s1's refcount goes up) >>> - pipe_context c1 is destroyed >>> - strb is destroyed >>> - strb->surface is destroyed (so s1's refcount is now 0 and we want >>> to >>> destroy it) >>> >>> At that point s1 references c1 which is not available any more, so >>> when we try to call ctx->surface_destroy to destroy s1 we crash. >>> >>> We discussed this a bit on IRC, and we agreed that the proper >>> solution, since surfaces outlive their context, is to make surfaces >>> screen-bound instead. I'm going to implement that unless someone >>> objects. >>> >>> As a side note, the same issue will happen with sampler_views, so >>> it'll get a similar fix. >> >> Sampler views and surfaces were previously objects bound to screen, and we >> changed that because of poor multithreading semantics. Per-context sampler >> views / render targets actually matches the 3D APIs semantics better, so I >> don't think that reverting is the solution. >> >> It looks to me that the issue here is that pipe_context should not be >> destroyed before the surfaces. strb->surface should only be used by one >> context, and should be destroyed before that context is destroyed. >> >> IIUC, strb matches GL renderbuffer semantics and can be shared by multiple >> context. If so, strb is treating pipe_surfaces as a entity shareable by >> contexts when really shouldn't. >> >> The solution is: >> - strb can only have pipe_resources, plus the key for the surface (face, >> level, etc) > > Another bit I don't get: since pipe_resources don't have a pointer to > the context, how do you go back to the corresponding context/surface > when all you have is the pipe_resource?
Short answer, you don't. Why do you need to? A pipe_surface is conceptually really just a means to supply the parameters to be used for rendering to a (color or depth) rendertarget. So you specify which level, layer(s) etc. of a resource will be used. That's all, analogous to pipe_sampler_view which does the same for texture sampling from a resource. Roland _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
