From 81faf0493508eca86af93811227c29d1260491dd Mon Sep 17 00:00:00 2001 From: Pavel Popov Date: Fri, 16 May 2014 11:57:12 +0700 Subject: [PATCH] i965: Properly return *RESET* status in glGetGraphicsResetStatusARB The glGetGraphicsResetStatusARB from ARB_robustness extension always returns GUILTY_CONTEXT_RESET_ARB and never returns NO_ERROR for guilty context with LOSE_CONTEXT_ON_RESET_ARB strategy. This is because Mesa returns GUILTY_CONTEXT_RESET_ARB if batch_active !=0 whereas kernel driver never reset batch_active and this variable always > 0 for guilty context. The same behaviour also can be observed for batch_pending and INNOCENT_CONTEXT_RESET_ARB. But spec says the following (http://www.opengl.org/registry/specs/ARB/robustness.txt): If a reset status other than NO_ERROR is returned and subsequent calls return NO_ERROR, the context reset was encountered and completed. If a reset status is repeatedly returned, the context may be in the process of resetting. 8. How should the application react to a reset context event? RESOLVED: For this extension, the application is expected to query the reset status until NO_ERROR is returned. If a reset is encountered, at least one *RESET* status will be returned. Once NO_ERROR is encountered, the application can safely destroy the old context and create a new one. The main problem is the context may be in the process of resetting and in this case a reset status should be repeatedly returned. But looks like the kernel driver returns nonzero active/pending only if the context reset has already been encountered and completed. For this reason the *RESET* status cannot be repeatedly returned and should be returned only once. The reset_count and brw->reset_count variables can be used to control that glGetGraphicsResetStatusARB returns *RESET* status only once for each context. Note the i915 triggers reset_count twice which allows to return correct reset count immediately after active/pending have been incremented. Signed-off-by: Pavel Popov --- src/mesa/drivers/dri/i965/brw_reset.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/src/mesa/drivers/dri/i965/brw_reset.c b/src/mesa/drivers/dri/i965/brw_reset.c index 7eca1bc..d2d051e 100644 --- a/src/mesa/drivers/dri/i965/brw_reset.c +++ b/src/mesa/drivers/dri/i965/brw_reset.c @@ -42,6 +42,14 @@ brw_get_graphics_reset_status(struct gl_context *ctx) */ assert(brw->hw_ctx != NULL); + /* + * A reset status other than NO_ERROR was returned last time. I915 returns + * nonzero active/pending only if reset has been encountered and completed. + * Return NO_ERROR from now on. + */ + if (brw->reset_count != 0) + return GL_NO_ERROR; + err = drm_intel_get_reset_stats(brw->hw_ctx, &reset_count, &active, &pending); if (err) @@ -50,18 +58,19 @@ brw_get_graphics_reset_status(struct gl_context *ctx) /* A reset was observed while a batch from this context was executing. * Assume that this context was at fault. */ - if (active != 0) + if (active != 0) { + brw->reset_count = reset_count; return GL_GUILTY_CONTEXT_RESET_ARB; + } /* A reset was observed while a batch from this context was in progress, * but the batch was not executing. In this case, assume that the context * was not at fault. */ - if (pending != 0) + if (pending != 0) { + brw->reset_count = reset_count; return GL_INNOCENT_CONTEXT_RESET_ARB; - - /* FINISHME: Should we report anything if reset_count > brw->reset_count? - */ + } return GL_NO_ERROR; } -- 1.8.3.2