diff options
Diffstat (limited to 'drivers/gpu/drm/i915/gt/intel_engine.h')
| -rw-r--r-- | drivers/gpu/drm/i915/gt/intel_engine.h | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_engine.h b/drivers/gpu/drm/i915/gt/intel_engine.h index 29c8c03c5caa..b469de0dd9b6 100644 --- a/drivers/gpu/drm/i915/gt/intel_engine.h +++ b/drivers/gpu/drm/i915/gt/intel_engine.h @@ -107,7 +107,20 @@ execlists_num_ports(const struct intel_engine_execlists * const execlists) static inline struct i915_request * execlists_active(const struct intel_engine_execlists *execlists) { - return *READ_ONCE(execlists->active); + struct i915_request * const *cur, * const *old, *active; + + cur = READ_ONCE(execlists->active); + smp_rmb(); /* pairs with overwrite protection in process_csb() */ + do { + old = cur; + + active = READ_ONCE(*cur); + cur = READ_ONCE(execlists->active); + + smp_rmb(); /* and complete the seqlock retry */ + } while (unlikely(cur != old)); + + return active; } static inline void |