3.2.56-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Ville Syrjälä <ville.syrj...@linux.intel.com>
commit 753b1ad4a281b0663329409d410243e91825c323 upstream.
intel_ring_cachline_align() emits MI_NOOPs until the ring tail is
aligned to a cacheline boundary.
Cc: Bjoern C <l...@call-home.ch>
Cc: Alexandru DAMIAN <alexandru.dam...@intel.com>
Cc: Enrico Tagliavini <enrico.tagliav...@gmail.com>
Suggested-by: Chris Wilson <ch...@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrj...@linux.intel.com>
Reviewed-by: Chris Wilson <ch...@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vet...@ffwll.ch>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---
drivers/gpu/drm/i915/intel_ringbuffer.c | 21 +++++++++++++++++++++
drivers/gpu/drm/i915/intel_ringbuffer.h | 1 +
2 files changed, 22 insertions(+)
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -1213,6 +1213,27 @@ int intel_ring_begin(struct intel_ring_b
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)
{
ring->tail &= ring->size - 1;
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -174,6 +174,7 @@ static inline int intel_wait_ring_idle(s
}
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)
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
