diff options
| author |   Vinay Belgaumkar <vinay.belgaumkar@intel.com> | 2025-04-28 11:35:55 -0700 |
|---|---|---|
| committer |   Jani Nikula <jani.nikula@intel.com> | 2025-05-05 12:36:04 +0300 |
| commit | 936b73feab5cd7eae8fe3d08a7ac9b1f8ac68042 (patch) | |
| tree | 460d68c6d389282c9faff2a4ce349f9a30804c77 | |
| parent | Linux 6.15-rc5 (diff) | |
| download | wireguard-linux-936b73feab5cd7eae8fe3d08a7ac9b1f8ac68042.tar.xz wireguard-linux-936b73feab5cd7eae8fe3d08a7ac9b1f8ac68042.zip | |
drm/i915/slpc: Balance the inc/dec for num_waiters
As seen in some recent failures, SLPC num_waiters value is < 0.
This happens because the inc/dec are not balanced. We should skip
decrement for the same conditions as the increment. Currently, we
do that for power saving profile mode. This patch also ensures that
num_waiters is incremented in the case min_softlimit is at boost
freq. It ensures that we don't reduce the frequency while this request
is in flight.
v2: Add Fixes tags
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/13598
Fixes: f864a29afc32 ("drm/i915/slpc: Optmize waitboost for SLPC")
Fixes: 4a82ceb04ad4 ("drm/i915/slpc: Add sysfs for SLPC power profiles")
Cc: Sk Anirban <sk.anirban@intel.com>
Reviewed-by: Sk Anirban <sk.anirban@intel.com>
Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Link: https://lore.kernel.org/r/20250428183555.3250021-1-vinay.belgaumkar@intel.com
(cherry picked from commit d26e55085f4b7a63677670db827541209257b313)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
| -rw-r--r-- | drivers/gpu/drm/i915/gt/intel_rps.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_rps.c b/drivers/gpu/drm/i915/gt/intel_rps.c index 64e9317f58fb..71ee01d9ef64 100644 --- a/drivers/gpu/drm/i915/gt/intel_rps.c +++ b/drivers/gpu/drm/i915/gt/intel_rps.c @@ -1001,6 +1001,10 @@ void intel_rps_dec_waiters(struct intel_rps *rps) if (rps_uses_slpc(rps)) { slpc = rps_to_slpc(rps); + /* Don't decrement num_waiters for req where increment was skipped */ + if (slpc->power_profile == SLPC_POWER_PROFILES_POWER_SAVING) + return; + intel_guc_slpc_dec_waiters(slpc); } else { atomic_dec(&rps->num_waiters); @@ -1029,11 +1033,15 @@ void intel_rps_boost(struct i915_request *rq) if (slpc->power_profile == SLPC_POWER_PROFILES_POWER_SAVING) return; - if (slpc->min_freq_softlimit >= slpc->boost_freq) - return; - /* Return if old value is non zero */ if (!atomic_fetch_inc(&slpc->num_waiters)) { + /* + * Skip queuing boost work if frequency is already boosted, + * but still increment num_waiters. + */ + if (slpc->min_freq_softlimit >= slpc->boost_freq) + return; + GT_TRACE(rps_to_gt(rps), "boost fence:%llx:%llx\n", rq->fence.context, rq->fence.seqno); queue_work(rps_to_gt(rps)->i915->unordered_wq, |