@@ -1453,6 +1453,27 @@ int intel_ring_begin(struct intel_ring_buffer *ring,
return 0;
}
+/* Align the ring tail to a cacheline boundary */
+int intel_ring_cacheline_align(struct intel_ring_buffer *ring)
+{
+ int num_dwords = (64 - (ring->tail & 63)) / sizeof(uint32_t);
+ int ret;
+
+ if (num_dwords == 0)
+ return 0;
+
+ ret = intel_ring_begin(ring, num_dwords);
+ if (ret)
+ return ret;
+
+ while (num_dwords--)
+ intel_ring_emit(ring, MI_NOOP);
+
+ intel_ring_advance(ring);
+
+ return 0;
+}
+
void intel_ring_advance(struct intel_ring_buffer *ring)
{
struct drm_i915_private *dev_priv = ring->dev->dev_private;
@@ -200,6 +200,7 @@ intel_read_status_page(struct intel_ring_buffer *ring,
void intel_cleanup_ring_buffer(struct intel_ring_buffer *ring);
int __must_check intel_ring_begin(struct intel_ring_buffer *ring, int n);
+int __must_check intel_ring_cacheline_align(struct intel_ring_buffer *ring);
static inline void intel_ring_emit(struct intel_ring_buffer *ring,
u32 data)
{
This is a note to let you know that I have just added a patch titled drm/i915: Add intel_ring_cachline_align() to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue This patch is scheduled to be released in version 3.8.13.20. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.8.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From 99975c376d760878761b6630d55a8e68d0c12e90 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@linux.intel.com> Date: Tue, 11 Feb 2014 19:52:05 +0200 Subject: drm/i915: Add intel_ring_cachline_align() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit 753b1ad4a281b0663329409d410243e91825c323 upstream. intel_ring_cachline_align() emits MI_NOOPs until the ring tail is aligned to a cacheline boundary. Cc: Bjoern C <lkml@call-home.ch> Cc: Alexandru DAMIAN <alexandru.damian@intel.com> Cc: Enrico Tagliavini <enrico.tagliavini@gmail.com> Suggested-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/gpu/drm/i915/intel_ringbuffer.c | 21 +++++++++++++++++++++ drivers/gpu/drm/i915/intel_ringbuffer.h | 1 + 2 files changed, 22 insertions(+) -- 1.8.3.2