Chris Wilson
2018-12-07 13:40:37 UTC
Adding an extra MI_STORE_DWORD_IMM to the gpu relocation path for gen3
was good, but still not good enough. To survive 24+ hours under test we
needed to perform not one, not two but three extra store-dw. Doing so
for each GPU relocation was a little unsightly and since we need to
worry about userspace hitting the same issues, we should apply the dummy
store-dw into the EMIT_FLUSH.
Fixes: 7dd4f6729f92 ("drm/i915: Async GPU relocation processing")
References: 7fa28e146994 ("drm/i915: Write GPU relocs harder with gen3")
Testcase: igt/gem_tiled_fence_blits # blb/pnv
Signed-off-by: Chris Wilson <***@chris-wilson.co.uk>
Cc: Joonas Lahtinen <***@linux.intel.com>
---
drivers/gpu/drm/i915/i915_gem_execbuffer.c | 7 +------
drivers/gpu/drm/i915/intel_ringbuffer.c | 15 ++++++++++++---
2 files changed, 13 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index 10a4afb4f235..786d719e652d 100644
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -1268,7 +1268,7 @@ relocate_entry(struct i915_vma *vma,
else if (gen >= 4)
len = 4;
else
- len = 6;
+ len = 3;
batch = reloc_gpu(eb, vma, len);
if (IS_ERR(batch))
@@ -1309,11 +1309,6 @@ relocate_entry(struct i915_vma *vma,
*batch++ = MI_STORE_DWORD_IMM | MI_MEM_VIRTUAL;
*batch++ = addr;
*batch++ = target_offset;
-
- /* And again for good measure (blb/pnv) */
- *batch++ = MI_STORE_DWORD_IMM | MI_MEM_VIRTUAL;
- *batch++ = addr;
- *batch++ = target_offset;
}
goto out;
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 74a4d587c312..02f6a9b81083 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -69,19 +69,28 @@ unsigned int intel_ring_update_space(struct intel_ring *ring)
static int
gen2_render_ring_flush(struct i915_request *rq, u32 mode)
{
+ unsigned int num_store_dw;
u32 cmd, *cs;
cmd = MI_FLUSH;
-
+ num_store_dw = 0;
if (mode & EMIT_INVALIDATE)
cmd |= MI_READ_FLUSH;
+ if (mode & EMIT_FLUSH)
+ num_store_dw = 4;
- cs = intel_ring_begin(rq, 2);
+ cs = intel_ring_begin(rq, 2 + 3 * num_store_dw);
if (IS_ERR(cs))
return PTR_ERR(cs);
*cs++ = cmd;
- *cs++ = MI_NOOP;
+ while (num_store_dw--) {
+ *cs++ = MI_STORE_DWORD_IMM | MI_MEM_VIRTUAL;
+ *cs++ = i915_scratch_offset(rq->i915);
+ *cs++ = 0;
+ }
+ *cs++ = MI_FLUSH | MI_NO_WRITE_FLUSH;
+
intel_ring_advance(rq, cs);
return 0;
was good, but still not good enough. To survive 24+ hours under test we
needed to perform not one, not two but three extra store-dw. Doing so
for each GPU relocation was a little unsightly and since we need to
worry about userspace hitting the same issues, we should apply the dummy
store-dw into the EMIT_FLUSH.
Fixes: 7dd4f6729f92 ("drm/i915: Async GPU relocation processing")
References: 7fa28e146994 ("drm/i915: Write GPU relocs harder with gen3")
Testcase: igt/gem_tiled_fence_blits # blb/pnv
Signed-off-by: Chris Wilson <***@chris-wilson.co.uk>
Cc: Joonas Lahtinen <***@linux.intel.com>
---
drivers/gpu/drm/i915/i915_gem_execbuffer.c | 7 +------
drivers/gpu/drm/i915/intel_ringbuffer.c | 15 ++++++++++++---
2 files changed, 13 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index 10a4afb4f235..786d719e652d 100644
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -1268,7 +1268,7 @@ relocate_entry(struct i915_vma *vma,
else if (gen >= 4)
len = 4;
else
- len = 6;
+ len = 3;
batch = reloc_gpu(eb, vma, len);
if (IS_ERR(batch))
@@ -1309,11 +1309,6 @@ relocate_entry(struct i915_vma *vma,
*batch++ = MI_STORE_DWORD_IMM | MI_MEM_VIRTUAL;
*batch++ = addr;
*batch++ = target_offset;
-
- /* And again for good measure (blb/pnv) */
- *batch++ = MI_STORE_DWORD_IMM | MI_MEM_VIRTUAL;
- *batch++ = addr;
- *batch++ = target_offset;
}
goto out;
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 74a4d587c312..02f6a9b81083 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -69,19 +69,28 @@ unsigned int intel_ring_update_space(struct intel_ring *ring)
static int
gen2_render_ring_flush(struct i915_request *rq, u32 mode)
{
+ unsigned int num_store_dw;
u32 cmd, *cs;
cmd = MI_FLUSH;
-
+ num_store_dw = 0;
if (mode & EMIT_INVALIDATE)
cmd |= MI_READ_FLUSH;
+ if (mode & EMIT_FLUSH)
+ num_store_dw = 4;
- cs = intel_ring_begin(rq, 2);
+ cs = intel_ring_begin(rq, 2 + 3 * num_store_dw);
if (IS_ERR(cs))
return PTR_ERR(cs);
*cs++ = cmd;
- *cs++ = MI_NOOP;
+ while (num_store_dw--) {
+ *cs++ = MI_STORE_DWORD_IMM | MI_MEM_VIRTUAL;
+ *cs++ = i915_scratch_offset(rq->i915);
+ *cs++ = 0;
+ }
+ *cs++ = MI_FLUSH | MI_NO_WRITE_FLUSH;
+
intel_ring_advance(rq, cs);
return 0;
--
2.20.0.rc2
2.20.0.rc2