drm/i915: Performed deferred clflush inside set-cache-level
Currently we are hitting the WARN inside
i915_gem_object_set_cache_level() as we can now have an unbound object
in the GTT write domain (due to 43566dedde54f9 "drm/i915: Broaden
application of set-domain(GTT)"). To avoid the warning, we need to track
when we elided the clflush on a cacheable object and then evict the
cache for the object when we move the object out of a cacheable domain.
Reported-by: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Tested-by: Jani Nikula <jani.nikula@intel.com>
Testcase: igt/gem_mmap_wc/set-cache-level
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=88607
Tested-by: huax.lu@intel.com
[danvet: Split if into nested if as discussion on the m-l.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 2a4d1f0..a0264aa 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -3637,11 +3637,14 @@
* snooping behaviour occurs naturally as the result of our domain
* tracking.
*/
- if (!force && cpu_cache_is_coherent(obj->base.dev, obj->cache_level))
+ if (!force && cpu_cache_is_coherent(obj->base.dev, obj->cache_level)) {
+ obj->cache_dirty = true;
return false;
+ }
trace_i915_gem_object_clflush(obj);
drm_clflush_sg(obj->pages);
+ obj->cache_dirty = false;
return true;
}
@@ -3824,27 +3827,11 @@
vma->node.color = cache_level;
obj->cache_level = cache_level;
- if (cpu_write_needs_clflush(obj)) {
- u32 old_read_domains, old_write_domain;
-
- /* If we're coming from LLC cached, then we haven't
- * actually been tracking whether the data is in the
- * CPU cache or not, since we only allow one bit set
- * in obj->write_domain and have been skipping the clflushes.
- * Just set it to the CPU cache for now.
- */
- i915_gem_object_retire(obj);
- WARN_ON(obj->base.write_domain & ~I915_GEM_DOMAIN_CPU);
-
- old_read_domains = obj->base.read_domains;
- old_write_domain = obj->base.write_domain;
-
- obj->base.read_domains = I915_GEM_DOMAIN_CPU;
- obj->base.write_domain = I915_GEM_DOMAIN_CPU;
-
- trace_i915_gem_object_change_domain(obj,
- old_read_domains,
- old_write_domain);
+ if (obj->cache_dirty &&
+ obj->base.write_domain != I915_GEM_DOMAIN_CPU &&
+ cpu_write_needs_clflush(obj)) {
+ if (i915_gem_clflush_object(obj, true))
+ i915_gem_chipset_flush(obj->base.dev);
}
return 0;