diff options
| author | Damien Lespiau <damien.lespiau@intel.com> | 2015-02-14 18:30:29 +0000 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2015-02-24 00:07:05 +0100 |
| commit | b76687910693b1f6c32a3251a8291d67363bba34 (patch) | |
| tree | 6452da876111dc6dbd93be1913ec0df3186e3f5b /drivers/gpu/drm/i915/i915_dma.c | |
| parent | cb0a08c1ed7daa16d13876e3e1b8787d95b25b0e (diff) | |
drm/i915/skl: Tune IZ hashing when subslices are unbalanced
When one EU is disabled in a particular subslice, we can tune how the
work is spread between subslices to improve EU utilization.
v2: - Use a bitfield to record which subslice(s) has(have) 7 EUs. That
will also make the machinery work if several sublices have 7 EUs.
(Jeff Mcgee)
- Only apply the different hashing algorithm if the slice is
effectively unbalanced by checking there's a single subslice with
7 EUs. (Jeff Mcgee)
v3: Fix typo in comment (Jeff Mcgee)
Issue: VIZ-3845
Cc: Jeff Mcgee <jeff.mcgee@intel.com>
Reviewed-by: Jeff Mcgee <jeff.mcgee@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/gpu/drm/i915/i915_dma.c')
| -rw-r--r-- | drivers/gpu/drm/i915/i915_dma.c | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c index 9a365b40b50e..f9992ca11d10 100644 --- a/drivers/gpu/drm/i915/i915_dma.c +++ b/drivers/gpu/drm/i915/i915_dma.c @@ -650,13 +650,24 @@ static void intel_device_info_runtime_init(struct drm_device *dev) continue; for (ss = 0; ss < ss_max; ss++) { + u32 n_disabled; + if (ss_disable & (0x1 << ss)) /* skip disabled subslice */ continue; - info->eu_total += eu_max - - hweight8(eu_disable[s] >> - (ss * eu_max)); + n_disabled = hweight8(eu_disable[s] >> + (ss * eu_max)); + + /* + * Record which subslice(s) has(have) 7 EUs. we + * can tune the hash used to spread work among + * subslices if they are unbalanced. + */ + if (eu_max - n_disabled == 7) + info->subslice_7eu[s] |= 1 << ss; + + info->eu_total += eu_max - n_disabled; } } |