[Intel-gfx] [PATCH 08/18] drm/i915/guc: Defer context unpin until scheduling is disabled
With GuC scheduling, it isn't safe to unpin a context while scheduling is enabled for that context as the GuC may touch some of the pinned state (e.g. LRC). To ensure scheduling isn't enabled when an unpin is done, a call back is added to intel_context_unpin when pin count == 1 to disable scheduling for that context. When the response CTB is received it is safe to do the final unpin. Future patches may add a heuristic / delay to schedule the disable call back to avoid thrashing on schedule enable / disable. v2: (John H) - s/drm_dbg/drm_err (Daneiel) - Clean up sched state function Cc: John Harrison Signed-off-by: Matthew Brost Reviewed-by: John Harrison --- drivers/gpu/drm/i915/gt/intel_context.c | 4 +- drivers/gpu/drm/i915/gt/intel_context.h | 27 +++- drivers/gpu/drm/i915/gt/intel_context_types.h | 2 + drivers/gpu/drm/i915/gt/uc/intel_guc.h| 2 + drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c | 3 + .../gpu/drm/i915/gt/uc/intel_guc_submission.c | 146 +- 6 files changed, 180 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c index ad7197c5910f..3d5b4116617f 100644 --- a/drivers/gpu/drm/i915/gt/intel_context.c +++ b/drivers/gpu/drm/i915/gt/intel_context.c @@ -306,9 +306,9 @@ int __intel_context_do_pin(struct intel_context *ce) return err; } -void intel_context_unpin(struct intel_context *ce) +void __intel_context_do_unpin(struct intel_context *ce, int sub) { - if (!atomic_dec_and_test(&ce->pin_count)) + if (!atomic_sub_and_test(sub, &ce->pin_count)) return; CE_TRACE(ce, "unpin\n"); diff --git a/drivers/gpu/drm/i915/gt/intel_context.h b/drivers/gpu/drm/i915/gt/intel_context.h index b10cbe8fee99..974ef85320c2 100644 --- a/drivers/gpu/drm/i915/gt/intel_context.h +++ b/drivers/gpu/drm/i915/gt/intel_context.h @@ -113,7 +113,32 @@ static inline void __intel_context_pin(struct intel_context *ce) atomic_inc(&ce->pin_count); } -void intel_context_unpin(struct intel_context *ce); +void __intel_context_do_unpin(struct intel_context *ce, int sub); + +static inline void intel_context_sched_disable_unpin(struct intel_context *ce) +{ + __intel_context_do_unpin(ce, 2); +} + +static inline void intel_context_unpin(struct intel_context *ce) +{ + if (!ce->ops->sched_disable) { + __intel_context_do_unpin(ce, 1); + } else { + /* +* Move ownership of this pin to the scheduling disable which is +* an async operation. When that operation completes the above +* intel_context_sched_disable_unpin is called potentially +* unpinning the context. +*/ + while (!atomic_add_unless(&ce->pin_count, -1, 1)) { + if (atomic_cmpxchg(&ce->pin_count, 1, 2) == 1) { + ce->ops->sched_disable(ce); + break; + } + } + } +} void intel_context_enter_engine(struct intel_context *ce); void intel_context_exit_engine(struct intel_context *ce); diff --git a/drivers/gpu/drm/i915/gt/intel_context_types.h b/drivers/gpu/drm/i915/gt/intel_context_types.h index e0e3a937f709..4a5518d295c2 100644 --- a/drivers/gpu/drm/i915/gt/intel_context_types.h +++ b/drivers/gpu/drm/i915/gt/intel_context_types.h @@ -43,6 +43,8 @@ struct intel_context_ops { void (*enter)(struct intel_context *ce); void (*exit)(struct intel_context *ce); + void (*sched_disable)(struct intel_context *ce); + void (*reset)(struct intel_context *ce); void (*destroy)(struct kref *kref); }; diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.h b/drivers/gpu/drm/i915/gt/uc/intel_guc.h index 7fd6c3e343e4..4d470ebeda95 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc.h +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.h @@ -248,6 +248,8 @@ int intel_guc_reset_engine(struct intel_guc *guc, int intel_guc_deregister_done_process_msg(struct intel_guc *guc, const u32 *msg, u32 len); +int intel_guc_sched_done_process_msg(struct intel_guc *guc, +const u32 *msg, u32 len); void intel_guc_load_status(struct intel_guc *guc, struct drm_printer *p); diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c index 28ff82c5be45..019b25ff1888 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c @@ -932,6 +932,9 @@ static int ct_process_request(struct intel_guc_ct *ct, struct ct_incoming_msg *r ret = intel_guc_deregister_done_process_msg(guc, payload, len); break; + case INTEL_GUC_ACTION_SCHED_CONTEXT_MODE_DONE: + ret = intel_guc_sched_done_process
[Intel-gfx] [PATCH 08/18] drm/i915/guc: Defer context unpin until scheduling is disabled
With GuC scheduling, it isn't safe to unpin a context while scheduling is enabled for that context as the GuC may touch some of the pinned state (e.g. LRC). To ensure scheduling isn't enabled when an unpin is done, a call back is added to intel_context_unpin when pin count == 1 to disable scheduling for that context. When the response CTB is received it is safe to do the final unpin. Future patches may add a heuristic / delay to schedule the disable call back to avoid thrashing on schedule enable / disable. v2: (John H) - s/drm_dbg/drm_err (Daneiel) - Clean up sched state function Cc: John Harrison Signed-off-by: Matthew Brost Reviewed-by: John Harrison --- drivers/gpu/drm/i915/gt/intel_context.c | 4 +- drivers/gpu/drm/i915/gt/intel_context.h | 27 +++- drivers/gpu/drm/i915/gt/intel_context_types.h | 2 + drivers/gpu/drm/i915/gt/uc/intel_guc.h| 2 + drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c | 3 + .../gpu/drm/i915/gt/uc/intel_guc_submission.c | 146 +- 6 files changed, 180 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c index ad7197c5910f..3d5b4116617f 100644 --- a/drivers/gpu/drm/i915/gt/intel_context.c +++ b/drivers/gpu/drm/i915/gt/intel_context.c @@ -306,9 +306,9 @@ int __intel_context_do_pin(struct intel_context *ce) return err; } -void intel_context_unpin(struct intel_context *ce) +void __intel_context_do_unpin(struct intel_context *ce, int sub) { - if (!atomic_dec_and_test(&ce->pin_count)) + if (!atomic_sub_and_test(sub, &ce->pin_count)) return; CE_TRACE(ce, "unpin\n"); diff --git a/drivers/gpu/drm/i915/gt/intel_context.h b/drivers/gpu/drm/i915/gt/intel_context.h index b10cbe8fee99..974ef85320c2 100644 --- a/drivers/gpu/drm/i915/gt/intel_context.h +++ b/drivers/gpu/drm/i915/gt/intel_context.h @@ -113,7 +113,32 @@ static inline void __intel_context_pin(struct intel_context *ce) atomic_inc(&ce->pin_count); } -void intel_context_unpin(struct intel_context *ce); +void __intel_context_do_unpin(struct intel_context *ce, int sub); + +static inline void intel_context_sched_disable_unpin(struct intel_context *ce) +{ + __intel_context_do_unpin(ce, 2); +} + +static inline void intel_context_unpin(struct intel_context *ce) +{ + if (!ce->ops->sched_disable) { + __intel_context_do_unpin(ce, 1); + } else { + /* +* Move ownership of this pin to the scheduling disable which is +* an async operation. When that operation completes the above +* intel_context_sched_disable_unpin is called potentially +* unpinning the context. +*/ + while (!atomic_add_unless(&ce->pin_count, -1, 1)) { + if (atomic_cmpxchg(&ce->pin_count, 1, 2) == 1) { + ce->ops->sched_disable(ce); + break; + } + } + } +} void intel_context_enter_engine(struct intel_context *ce); void intel_context_exit_engine(struct intel_context *ce); diff --git a/drivers/gpu/drm/i915/gt/intel_context_types.h b/drivers/gpu/drm/i915/gt/intel_context_types.h index e0e3a937f709..4a5518d295c2 100644 --- a/drivers/gpu/drm/i915/gt/intel_context_types.h +++ b/drivers/gpu/drm/i915/gt/intel_context_types.h @@ -43,6 +43,8 @@ struct intel_context_ops { void (*enter)(struct intel_context *ce); void (*exit)(struct intel_context *ce); + void (*sched_disable)(struct intel_context *ce); + void (*reset)(struct intel_context *ce); void (*destroy)(struct kref *kref); }; diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.h b/drivers/gpu/drm/i915/gt/uc/intel_guc.h index 30773cd699f5..03b7222b04a2 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc.h +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.h @@ -241,6 +241,8 @@ int intel_guc_reset_engine(struct intel_guc *guc, int intel_guc_deregister_done_process_msg(struct intel_guc *guc, const u32 *msg, u32 len); +int intel_guc_sched_done_process_msg(struct intel_guc *guc, +const u32 *msg, u32 len); void intel_guc_load_status(struct intel_guc *guc, struct drm_printer *p); diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c index 28ff82c5be45..019b25ff1888 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c @@ -932,6 +932,9 @@ static int ct_process_request(struct intel_guc_ct *ct, struct ct_incoming_msg *r ret = intel_guc_deregister_done_process_msg(guc, payload, len); break; + case INTEL_GUC_ACTION_SCHED_CONTEXT_MODE_DONE: + ret = intel_guc_sched_done_process