On Mon, Mar 04, 2024 at 03:34:50PM -0800, Vinay Belgaumkar wrote: > Allow user to provide a low latency context hint. When set, KMD > sends a hint to GuC which results in special handling for this > context. SLPC will ramp the GT frequency aggressively every time > it switches to this context. The down freq threshold will also be > lower so GuC will ramp down the GT freq for this context more slowly. > We also disable waitboost for this context as that will interfere with > the strategy. > > We need to enable the use of SLPC Compute strategy during init, but > it will apply only to contexts that set this bit during context > creation. > > Userland can check whether this feature is supported using a new param- > I915_PARAM_HAS_CONTEXT_FREQ_HINTS. This flag is true for all guc submission > enabled platforms as they use SLPC for frequency management. > > The Mesa usage model for this flag is here - > https://gitlab.freedesktop.org/sushmave/mesa/-/commits/compute_hint > > v2: Rename flags as per review suggestions (Rodrigo, Tvrtko). > Also, use flag bits in intel_context as it allows finer control for > toggling per engine if needed (Tvrtko). > > v3: Minor review comments (Tvrtko) > > Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> > Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxxxxxxxx> > Cc: Sushma Venkatesh Reddy <sushma.venkatesh.reddy@xxxxxxxxx> > Acked-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> > Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@xxxxxxxxx> > --- > drivers/gpu/drm/i915/gem/i915_gem_context.c | 16 ++++++++++++-- > .../gpu/drm/i915/gem/i915_gem_context_types.h | 1 + > drivers/gpu/drm/i915/gt/intel_context_types.h | 1 + > drivers/gpu/drm/i915/gt/intel_rps.c | 4 ++++ > .../drm/i915/gt/uc/abi/guc_actions_slpc_abi.h | 21 +++++++++++++++++++ > drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c | 17 +++++++++++++++ > drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h | 1 + > .../gpu/drm/i915/gt/uc/intel_guc_submission.c | 6 ++++++ > drivers/gpu/drm/i915/i915_getparam.c | 6 ++++++ > include/uapi/drm/i915_drm.h | 15 +++++++++++++ > 10 files changed, 86 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c > index dcbfe32fd30c..81f65cab1330 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_context.c > +++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c > @@ -879,6 +879,7 @@ static int set_proto_ctx_param(struct drm_i915_file_private *fpriv, > struct i915_gem_proto_context *pc, > struct drm_i915_gem_context_param *args) > { > + struct drm_i915_private *i915 = fpriv->i915; > int ret = 0; > > switch (args->param) { > @@ -904,6 +905,13 @@ static int set_proto_ctx_param(struct drm_i915_file_private *fpriv, > pc->user_flags &= ~BIT(UCONTEXT_BANNABLE); > break; > > + case I915_CONTEXT_PARAM_LOW_LATENCY: > + if (intel_uc_uses_guc_submission(&to_gt(i915)->uc)) > + pc->user_flags |= BIT(UCONTEXT_LOW_LATENCY); > + else > + ret = -EINVAL; > + break; > + > case I915_CONTEXT_PARAM_RECOVERABLE: > if (args->size) > ret = -EINVAL; > @@ -992,6 +1000,9 @@ static int intel_context_set_gem(struct intel_context *ce, > if (sseu.slice_mask && !WARN_ON(ce->engine->class != RENDER_CLASS)) > ret = intel_context_reconfigure_sseu(ce, sseu); > > + if (test_bit(UCONTEXT_LOW_LATENCY, &ctx->user_flags)) > + __set_bit(CONTEXT_LOW_LATENCY, &ce->flags); > + > return ret; > } > > @@ -1630,6 +1641,9 @@ i915_gem_create_context(struct drm_i915_private *i915, > if (vm) > ctx->vm = vm; > > + /* Assign early so intel_context_set_gem can access these flags */ > + ctx->user_flags = pc->user_flags; > + > mutex_init(&ctx->engines_mutex); > if (pc->num_user_engines >= 0) { > i915_gem_context_set_user_engines(ctx); > @@ -1652,8 +1666,6 @@ i915_gem_create_context(struct drm_i915_private *i915, > * is no remap info, it will be a NOP. */ > ctx->remap_slice = ALL_L3_SLICES(i915); > > - ctx->user_flags = pc->user_flags; > - > for (i = 0; i < ARRAY_SIZE(ctx->hang_timestamp); i++) > ctx->hang_timestamp[i] = jiffies - CONTEXT_FAST_HANG_JIFFIES; > > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context_types.h b/drivers/gpu/drm/i915/gem/i915_gem_context_types.h > index 03bc7f9d191b..b6d97da63d1f 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_context_types.h > +++ b/drivers/gpu/drm/i915/gem/i915_gem_context_types.h > @@ -338,6 +338,7 @@ struct i915_gem_context { > #define UCONTEXT_BANNABLE 2 > #define UCONTEXT_RECOVERABLE 3 > #define UCONTEXT_PERSISTENCE 4 > +#define UCONTEXT_LOW_LATENCY 5 > > /** > * @flags: small set of booleans > diff --git a/drivers/gpu/drm/i915/gt/intel_context_types.h b/drivers/gpu/drm/i915/gt/intel_context_types.h > index 7eccbd70d89f..ed95a7b57cbb 100644 > --- a/drivers/gpu/drm/i915/gt/intel_context_types.h > +++ b/drivers/gpu/drm/i915/gt/intel_context_types.h > @@ -130,6 +130,7 @@ struct intel_context { > #define CONTEXT_PERMA_PIN 11 > #define CONTEXT_IS_PARKING 12 > #define CONTEXT_EXITING 13 > +#define CONTEXT_LOW_LATENCY 14 > > struct { > u64 timeout_us; > diff --git a/drivers/gpu/drm/i915/gt/intel_rps.c b/drivers/gpu/drm/i915/gt/intel_rps.c > index 9c6812257ac2..a929aa6e3c85 100644 > --- a/drivers/gpu/drm/i915/gt/intel_rps.c > +++ b/drivers/gpu/drm/i915/gt/intel_rps.c > @@ -1013,6 +1013,10 @@ void intel_rps_boost(struct i915_request *rq) > if (i915_request_signaled(rq) || i915_request_has_waitboost(rq)) > return; > > + /* Waitboost is not needed for contexts marked with a Freq hint */ > + if (test_bit(CONTEXT_LOW_LATENCY, &rq->context->flags)) > + return; > + > /* Serializes with i915_request_retire() */ > if (!test_and_set_bit(I915_FENCE_FLAG_BOOST, &rq->fence.flags)) { > struct intel_rps *rps = &READ_ONCE(rq->engine)->gt->rps; > diff --git a/drivers/gpu/drm/i915/gt/uc/abi/guc_actions_slpc_abi.h b/drivers/gpu/drm/i915/gt/uc/abi/guc_actions_slpc_abi.h > index 811add10c30d..c34674e797c6 100644 > --- a/drivers/gpu/drm/i915/gt/uc/abi/guc_actions_slpc_abi.h > +++ b/drivers/gpu/drm/i915/gt/uc/abi/guc_actions_slpc_abi.h > @@ -207,6 +207,27 @@ struct slpc_shared_data { > u8 reserved_mode_definition[4096]; > } __packed; > > +struct slpc_context_frequency_request { > + u32 frequency_request:16; > + u32 reserved:12; > + u32 is_compute:1; > + u32 ignore_busyness:1; > + u32 is_minimum:1; > + u32 is_predefined:1; > +} __packed; > + > +#define SLPC_CTX_FREQ_REQ_IS_COMPUTE REG_BIT(28) > + > +struct slpc_optimized_strategies { > + u32 compute:1; > + u32 async_flip:1; > + u32 media:1; > + u32 vsync_flip:1; > + u32 reserved:28; > +} __packed; > + > +#define SLPC_OPTIMIZED_STRATEGY_COMPUTE REG_BIT(0) > + > /** > * DOC: SLPC H2G MESSAGE FORMAT > * > diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c > index 3e681ab6fbf9..706fffca698b 100644 > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c > @@ -537,6 +537,20 @@ int intel_guc_slpc_get_min_freq(struct intel_guc_slpc *slpc, u32 *val) > return ret; > } > > +int intel_guc_slpc_set_strategy(struct intel_guc_slpc *slpc, u32 val) > +{ > + struct drm_i915_private *i915 = slpc_to_i915(slpc); > + intel_wakeref_t wakeref; > + int ret = 0; > + > + with_intel_runtime_pm(&i915->runtime_pm, wakeref) > + ret = slpc_set_param(slpc, > + SLPC_PARAM_STRATEGIES, > + val); > + > + return ret; > +} > + > int intel_guc_slpc_set_media_ratio_mode(struct intel_guc_slpc *slpc, u32 val) > { > struct drm_i915_private *i915 = slpc_to_i915(slpc); > @@ -711,6 +725,9 @@ int intel_guc_slpc_enable(struct intel_guc_slpc *slpc) > /* Set cached media freq ratio mode */ > intel_guc_slpc_set_media_ratio_mode(slpc, slpc->media_ratio_mode); > > + /* Enable SLPC Optimized Strategy for compute */ > + intel_guc_slpc_set_strategy(slpc, SLPC_OPTIMIZED_STRATEGY_COMPUTE); > + > return 0; > } > > diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h > index 6ac6503c39d4..1cb5fd44f05c 100644 > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h > @@ -45,5 +45,6 @@ void intel_guc_pm_intrmsk_enable(struct intel_gt *gt); > void intel_guc_slpc_boost(struct intel_guc_slpc *slpc); > void intel_guc_slpc_dec_waiters(struct intel_guc_slpc *slpc); > int intel_guc_slpc_set_ignore_eff_freq(struct intel_guc_slpc *slpc, bool val); > +int intel_guc_slpc_set_strategy(struct intel_guc_slpc *slpc, u32 val); > > #endif > diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > index cc076e9302ad..e5c645137cfe 100644 > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > @@ -2645,6 +2645,7 @@ MAKE_CONTEXT_POLICY_ADD(execution_quantum, EXECUTION_QUANTUM) > MAKE_CONTEXT_POLICY_ADD(preemption_timeout, PREEMPTION_TIMEOUT) > MAKE_CONTEXT_POLICY_ADD(priority, SCHEDULING_PRIORITY) > MAKE_CONTEXT_POLICY_ADD(preempt_to_idle, PREEMPT_TO_IDLE_ON_QUANTUM_EXPIRY) > +MAKE_CONTEXT_POLICY_ADD(slpc_ctx_freq_req, SLPM_GT_FREQUENCY) > > #undef MAKE_CONTEXT_POLICY_ADD > > @@ -2664,6 +2665,7 @@ static int guc_context_policy_init_v70(struct intel_context *ce, bool loop) > struct context_policy policy; > u32 execution_quantum; > u32 preemption_timeout; > + u32 slpc_ctx_freq_req = 0; > unsigned long flags; > int ret; > > @@ -2675,11 +2677,15 @@ static int guc_context_policy_init_v70(struct intel_context *ce, bool loop) > execution_quantum = engine->props.timeslice_duration_ms * 1000; > preemption_timeout = engine->props.preempt_timeout_ms * 1000; > > + if (ce && (ce->flags & BIT(CONTEXT_LOW_LATENCY))) > + slpc_ctx_freq_req |= SLPC_CTX_FREQ_REQ_IS_COMPUTE; > + > __guc_context_policy_start_klv(&policy, ce->guc_id.id); > > __guc_context_policy_add_priority(&policy, ce->guc_state.prio); > __guc_context_policy_add_execution_quantum(&policy, execution_quantum); > __guc_context_policy_add_preemption_timeout(&policy, preemption_timeout); > + __guc_context_policy_add_slpc_ctx_freq_req(&policy, slpc_ctx_freq_req); > > if (engine->flags & I915_ENGINE_WANT_FORCED_PREEMPTION) > __guc_context_policy_add_preempt_to_idle(&policy, 1); > diff --git a/drivers/gpu/drm/i915/i915_getparam.c b/drivers/gpu/drm/i915/i915_getparam.c > index 5c3fec63cb4c..95c58805b2a4 100644 > --- a/drivers/gpu/drm/i915/i915_getparam.c > +++ b/drivers/gpu/drm/i915/i915_getparam.c > @@ -155,6 +155,12 @@ int i915_getparam_ioctl(struct drm_device *dev, void *data, > */ > value = 1; > break; > + case I915_PARAM_HAS_CONTEXT_FREQ_HINT: > + if (intel_uc_uses_guc_submission(&to_gt(i915)->uc)) > + value = 1; > + else > + value = -EINVAL; > + break; > case I915_PARAM_HAS_CONTEXT_ISOLATION: > value = intel_engines_has_context_isolation(i915); > break; > diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h > index 1279a6b2bece..a8b3dd594831 100644 > --- a/include/uapi/drm/i915_drm.h > +++ b/include/uapi/drm/i915_drm.h > @@ -806,6 +806,12 @@ typedef struct drm_i915_irq_wait { > */ > #define I915_PARAM_PXP_STATUS 58 > > +/* > + * Query if kernel allows marking a context to send a Freq hint to SLPC. This > + * will enable use of the strategies allowed by the SLPC algorithm. > + */ > +#define I915_PARAM_HAS_CONTEXT_FREQ_HINT 59 > + > /* Must be kept compact -- no holes and well documented */ > > /** > @@ -2148,6 +2154,15 @@ struct drm_i915_gem_context_param { > * -EIO: The firmware did not succeed in creating the protected context. > */ > #define I915_CONTEXT_PARAM_PROTECTED_CONTENT 0xd > + > +/* > + * I915_CONTEXT_PARAM_IS_COMPUTE: > + * > + * Mark this context as a Compute related workload which requires aggressive GT > + * frequency scaling. Query I915_PARAM_HAS_CONTEXT_COMPUTE to check if the kernel > + * supports this functionality. > + */ > +#define I915_CONTEXT_PARAM_LOW_LATENCY 0xe > /* Must be kept compact -- no holes and well documented */ > > /** @value: Context parameter value to be set or queried */ > -- > 2.38.1 >
