drm/i915: Flush GPU relocs harder for gen3

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: 7dd4f6729f ("drm/i915: Async GPU relocation processing")
References: 7fa28e1469 ("drm/i915: Write GPU relocs harder with gen3")
Testcase: igt/gem_tiled_fence_blits # blb/pnv
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181207134037.11848-1-chris@chris-wilson.co.uk
This commit is contained in:
Chris Wilson 2018-12-07 13:40:37 +00:00
parent e6154e4cb8
commit a889580c08
2 changed files with 13 additions and 9 deletions

View File

@ -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;

View File

@ -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;