Attachment 60077 Details for Bug 48019 – Workaround occQuery fail

[patch] Workaround occQuery fail

0001-intel-snb-Workaround-pipe-control-write-failure-to-a.patch (text/plain), 3.12 KB, created by Chris Wilson on 2012-04-16 10:40:16 UTC

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Creator: Chris Wilson

Created: 2012-04-16 10:40:16 UTC

Size: 3.12 KB

patch

obsolete

>From 7cd8704593eedce1b3cf3badae39bca02cd2133e Mon Sep 17 00:00:00 2001
>From: Chris Wilson <chris@chris-wilson.co.uk>
>Date: Mon, 16 Apr 2012 11:47:07 +0100
>Subject: [PATCH] intel(snb): Workaround pipe control write failure to an
> active buffer
>
>For whatever reason, it turns out that if we use a pipe control to write
>out the occlusion query result, that write fails if the buffer has
>previously been used by the render pipeline. Currently the issue
>presents itself with buffers that are reused after being used as
>instruction caches, however the precise cause is unknown.
>
>Works around: https://bugs.freedesktop.org/show_bug.cgi?id=48019
>---
> src/mesa/drivers/dri/i965/brw_queryobj.c |   52 +++++++++++++++++++++++++++---
> 1 file changed, 48 insertions(+), 4 deletions(-)
>
>diff --git a/src/mesa/drivers/dri/i965/brw_queryobj.c b/src/mesa/drivers/dri/i965/brw_queryobj.c
>index 72b83f4..1b2f86f 100644
>--- a/src/mesa/drivers/dri/i965/brw_queryobj.c
>+++ b/src/mesa/drivers/dri/i965/brw_queryobj.c
>@@ -45,6 +45,50 @@
> #include "intel_batchbuffer.h"
> #include "intel_reg.h"
> 
>+#include <xf86drm.h>
>+
>+/* Emit an out-of-band command to clear the query bo before use */
>+static void clear_bo(struct brw_context *brw, drm_intel_bo *dst)
>+{
>+   struct intel_context *intel = &brw->intel;
>+   struct drm_i915_gem_execbuffer2 execbuf;
>+   struct drm_i915_gem_exec_object2 exec[2];
>+   struct drm_i915_gem_relocation_entry reloc[1];
>+   drm_intel_bo *bo = drm_intel_bo_alloc(intel->bufmgr, "clear", 4096, 0);
>+   uint32_t batch[6] = {
>+      2<<29 | 0x40<<22 | 0x3<<20 | 0x3,
>+      0x3<<24 | 0x0 << 16 | 4096,
>+      1 << 16 | 4096,
>+      dst->offset,
>+      0,
>+      MI_BATCH_BUFFER_END,
>+   };
>+   drm_intel_bo_subdata(bo, 0, sizeof(batch), batch);
>+
>+   memset(reloc, 0, sizeof(reloc));
>+   reloc->offset = 3 * sizeof(uint32_t);
>+   reloc->target_handle = dst->handle;
>+   reloc->presumed_offset = dst->offset;
>+   reloc->read_domains = I915_GEM_DOMAIN_RENDER;
>+   reloc->write_domain = I915_GEM_DOMAIN_RENDER;
>+
>+   memset(exec, 0, sizeof(exec));
>+   exec[0].handle = dst->handle;
>+   exec[1].handle = bo->handle;
>+   exec[1].relocation_count = 1;
>+   exec[1].relocs_ptr = (uintptr_t)reloc;
>+
>+   memset(&execbuf, 0, sizeof(execbuf));
>+   execbuf.buffers_ptr = (uintptr_t)exec;
>+   execbuf.buffer_count = 2;
>+   execbuf.batch_len = sizeof(batch);
>+   execbuf.flags = intel->gen >= 6 ? I915_EXEC_BLT : 0;
>+
>+   drmIoctl(intel->driFd, DRM_IOCTL_I915_GEM_EXECBUFFER2, &execbuf);
>+
>+   drm_intel_bo_unreference(bo);
>+}
>+
> /** Waits on the query object's BO and totals the results for this query */
> static void
> brw_queryobj_get_results(struct gl_context *ctx,
>@@ -311,10 +355,10 @@ brw_prepare_query_begin(struct brw_context *brw)
> 
>       brw->query.bo = drm_intel_bo_alloc(intel->bufmgr, "query", 4096, 1);
> 
>-      /* clear target buffer */
>-      drm_intel_bo_map(brw->query.bo, true);
>-      memset((char *)brw->query.bo->virtual, 0, 4096);
>-      drm_intel_bo_unmap(brw->query.bo);
>+      /* Note that we must always clear the bo as the hw may not write the
>+       * full 64-bits everytime. Sigh.
>+       */
>+      clear_bo(brw, brw->query.bo);
> 
>       brw->query.index = 0;
>    }
>-- 
>1.7.10
>

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Attachments on bug 48019: 59253 | 59474 | 60054 | 60077 | 63482

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