On Fre, 2012-02-03 at 17:32 +0000, Simon Farnsworth wrote: > r300g is able to sleep until a fence completes rather than busywait because > it creates a special buffer object and relocation that stays busy until the > CS containing the fence is finished. > > Copy the idea into r600g, and use it to sleep if the user asked for an > infinite wait, falling back to busywaiting if the user provided a timeout. > > Signed-off-by: Simon Farnsworth <simon.farnswo...@onelan.co.uk> > --- > > v3: At Dave Airlie's suggestion on dri-devel, make use of the BO to give us > a fighting chance of recovering after a GPU reset. > > We know that the fence will never be signalled by hardware if the dummy BO > has gone idle - we use that information to escape the loop. This might be a > useful addition to the 8.0 branch.
That's a nifty trick. :) > diff --git a/src/gallium/drivers/r600/r600_hw_context.c > b/src/gallium/drivers/r600/r600_hw_context.c > index 8eb8e6d..acfa494 100644 > --- a/src/gallium/drivers/r600/r600_hw_context.c > +++ b/src/gallium/drivers/r600/r600_hw_context.c > @@ -1623,6 +1623,13 @@ void r600_context_emit_fence(struct r600_context *ctx, > struct r600_resource *fen > ctx->pm4[ctx->pm4_cdwords++] = 0; /* DATA_HI */ > ctx->pm4[ctx->pm4_cdwords++] = PKT3(PKT3_NOP, 0, 0); > ctx->pm4[ctx->pm4_cdwords++] = r600_context_bo_reloc(ctx, fence_bo, > RADEON_USAGE_WRITE); > + > + /* Create a dummy BO so that fence_finish without a timeout can sleep > waiting for completion */ > + *sleep_bo = (struct r600_resource*) > + pipe_buffer_create(&ctx->screen->screen, > PIPE_BIND_CUSTOM, > + PIPE_USAGE_STAGING, 1); > + /* Add the fence as a dummy relocation. */ > + r600_context_bo_reloc(ctx, *sleep_bo, RADEON_USAGE_READWRITE); Sorry for only thinking of this now, but what's the advantage of doing this here, rather than in r600_create_fence()? Seems like that would be simpler and cleaner. -- Earthling Michel Dänzer | http://www.amd.com Libre software enthusiast | Debian, X and DRI developer _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
