From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BE9A2C07E99 for ; Fri, 9 Jul 2021 22:48:19 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 79878613B7 for ; Fri, 9 Jul 2021 22:48:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 79878613B7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id DC17C6E9AF; Fri, 9 Jul 2021 22:48:18 +0000 (UTC) Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by gabe.freedesktop.org (Postfix) with ESMTPS id 80ED86E9AD; Fri, 9 Jul 2021 22:48:16 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10040"; a="231562992" X-IronPort-AV: E=Sophos;i="5.84,228,1620716400"; d="scan'208";a="231562992" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Jul 2021 15:48:09 -0700 X-IronPort-AV: E=Sophos;i="5.84,228,1620716400"; d="scan'208";a="649660878" Received: from johnharr-mobl1.amr.corp.intel.com (HELO [10.212.142.243]) ([10.212.142.243]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Jul 2021 15:48:08 -0700 To: Matthew Brost , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org References: <20210624070516.21893-1-matthew.brost@intel.com> <20210624070516.21893-16-matthew.brost@intel.com> From: John Harrison Message-ID: <5e5bc311-19b4-5d83-6f32-8bf984b1a076@intel.com> Date: Fri, 9 Jul 2021 15:48:08 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <20210624070516.21893-16-matthew.brost@intel.com> Content-Language: en-GB Subject: Re: [Intel-gfx] [PATCH 15/47] drm/i915/guc: Defer context unpin until scheduling is disabled X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On 6/24/2021 00:04, Matthew Brost wrote: > 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. > > 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 | 145 +++++++++++++++++- > 6 files changed, 179 insertions(+), 4 deletions(-) > > diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c > index f750c826e19d..1499b8aace2a 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 f83a73a2b39f..8a7199afbe61 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 beafe55a9101..e7af6a2368f8 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 d44316dc914b..b43ec56986b5 100644 > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc.h > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.h > @@ -236,6 +236,8 @@ 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 42a7daef2ff6..7491f041859e 100644 > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c > @@ -905,6 +905,9 @@ 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_msg(guc, payload, len); > + break; > default: > ret = -EOPNOTSUPP; > break; > 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 49e5d460d54b..0386ccd5a481 100644 > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > @@ -70,6 +70,7 @@ > * possible for some of the bits to changing at the same time though. > */ > #define SCHED_STATE_NO_LOCK_ENABLED BIT(0) > +#define SCHED_STATE_NO_LOCK_PENDING_ENABLE BIT(1) > static inline bool context_enabled(struct intel_context *ce) > { > return (atomic_read(&ce->guc_sched_state_no_lock) & > @@ -87,6 +88,24 @@ static inline void clr_context_enabled(struct intel_context *ce) > &ce->guc_sched_state_no_lock); > } > > +static inline bool context_pending_enable(struct intel_context *ce) > +{ > + return (atomic_read(&ce->guc_sched_state_no_lock) & > + SCHED_STATE_NO_LOCK_PENDING_ENABLE); > +} > + > +static inline void set_context_pending_enable(struct intel_context *ce) > +{ > + atomic_or(SCHED_STATE_NO_LOCK_PENDING_ENABLE, > + &ce->guc_sched_state_no_lock); > +} > + > +static inline void clr_context_pending_enable(struct intel_context *ce) > +{ > + atomic_and((u32)~SCHED_STATE_NO_LOCK_PENDING_ENABLE, > + &ce->guc_sched_state_no_lock); > +} > + > /* > * Below is a set of functions which control the GuC scheduling state which > * require a lock, aside from the special case where the functions are called > @@ -95,6 +114,7 @@ static inline void clr_context_enabled(struct intel_context *ce) > */ > #define SCHED_STATE_WAIT_FOR_DEREGISTER_TO_REGISTER BIT(0) > #define SCHED_STATE_DESTROYED BIT(1) > +#define SCHED_STATE_PENDING_DISABLE BIT(2) > static inline void init_sched_state(struct intel_context *ce) > { > /* Only should be called from guc_lrc_desc_pin() */ > @@ -139,6 +159,24 @@ set_context_destroyed(struct intel_context *ce) > ce->guc_state.sched_state |= SCHED_STATE_DESTROYED; > } > > +static inline bool context_pending_disable(struct intel_context *ce) > +{ > + return (ce->guc_state.sched_state & SCHED_STATE_PENDING_DISABLE); > +} > + > +static inline void set_context_pending_disable(struct intel_context *ce) > +{ > + lockdep_assert_held(&ce->guc_state.lock); > + ce->guc_state.sched_state |= SCHED_STATE_PENDING_DISABLE; > +} > + > +static inline void clr_context_pending_disable(struct intel_context *ce) > +{ > + lockdep_assert_held(&ce->guc_state.lock); > + ce->guc_state.sched_state = > + (ce->guc_state.sched_state & ~SCHED_STATE_PENDING_DISABLE); > +} > + > static inline bool context_guc_id_invalid(struct intel_context *ce) > { > return (ce->guc_id == GUC_INVALID_LRC_ID); > @@ -231,6 +269,8 @@ static int guc_add_request(struct intel_guc *guc, struct i915_request *rq) > action[len++] = INTEL_GUC_ACTION_SCHED_CONTEXT_MODE_SET; > action[len++] = ce->guc_id; > action[len++] = GUC_CONTEXT_ENABLE; > + set_context_pending_enable(ce); > + intel_context_get(ce); > } else { > action[len++] = INTEL_GUC_ACTION_SCHED_CONTEXT; > action[len++] = ce->guc_id; > @@ -238,8 +278,12 @@ static int guc_add_request(struct intel_guc *guc, struct i915_request *rq) > > err = intel_guc_send_nb(guc, action, len); > > - if (!enabled && !err) > + if (!enabled && !err) { > set_context_enabled(ce); > + } else if (!enabled) { > + clr_context_pending_enable(ce); > + intel_context_put(ce); > + } > > return err; > } > @@ -831,6 +875,60 @@ static void guc_context_post_unpin(struct intel_context *ce) > lrc_post_unpin(ce); > } > > +static void __guc_context_sched_disable(struct intel_guc *guc, > + struct intel_context *ce, > + u16 guc_id) > +{ > + u32 action[] = { > + INTEL_GUC_ACTION_SCHED_CONTEXT_MODE_SET, > + guc_id, /* ce->guc_id not stable */ > + GUC_CONTEXT_DISABLE > + }; > + > + GEM_BUG_ON(guc_id == GUC_INVALID_LRC_ID); > + > + intel_context_get(ce); > + > + intel_guc_send_busy_loop(guc, action, ARRAY_SIZE(action), true); > +} > + > +static u16 prep_context_pending_disable(struct intel_context *ce) > +{ > + set_context_pending_disable(ce); > + clr_context_enabled(ce); > + > + return ce->guc_id; > +} > + > +static void guc_context_sched_disable(struct intel_context *ce) > +{ > + struct intel_guc *guc = ce_to_guc(ce); > + struct intel_runtime_pm *runtime_pm = &ce->engine->gt->i915->runtime_pm; > + unsigned long flags; > + u16 guc_id; > + intel_wakeref_t wakeref; > + > + if (context_guc_id_invalid(ce) || > + !lrc_desc_registered(guc, ce->guc_id)) { > + clr_context_enabled(ce); > + goto unpin; > + } > + > + if (!context_enabled(ce)) > + goto unpin; > + > + spin_lock_irqsave(&ce->guc_state.lock, flags); > + guc_id = prep_context_pending_disable(ce); > + spin_unlock_irqrestore(&ce->guc_state.lock, flags); > + > + with_intel_runtime_pm(runtime_pm, wakeref) > + __guc_context_sched_disable(guc, ce, guc_id); > + > + return; > +unpin: > + intel_context_sched_disable_unpin(ce); > +} > + > static inline void guc_lrc_desc_unpin(struct intel_context *ce) > { > struct intel_engine_cs *engine = ce->engine; > @@ -839,6 +937,7 @@ static inline void guc_lrc_desc_unpin(struct intel_context *ce) > > GEM_BUG_ON(!lrc_desc_registered(guc, ce->guc_id)); > GEM_BUG_ON(ce != __get_context(guc, ce->guc_id)); > + GEM_BUG_ON(context_enabled(ce)); > > spin_lock_irqsave(&ce->guc_state.lock, flags); > set_context_destroyed(ce); > @@ -920,6 +1019,8 @@ static const struct intel_context_ops guc_context_ops = { > .enter = intel_context_enter_engine, > .exit = intel_context_exit_engine, > > + .sched_disable = guc_context_sched_disable, > + > .reset = lrc_reset, > .destroy = guc_context_destroy, > }; > @@ -1352,3 +1453,45 @@ int intel_guc_deregister_done_process_msg(struct intel_guc *guc, > > return 0; > } > + > +int intel_guc_sched_done_process_msg(struct intel_guc *guc, > + const u32 *msg, > + u32 len) > +{ > + struct intel_context *ce; > + unsigned long flags; > + u32 desc_idx = msg[0]; > + > + if (unlikely(len < 2)) { > + drm_dbg(&guc_to_gt(guc)->i915->drm, "Invalid length %u", len); > + return -EPROTO; > + } > + > + ce = g2h_context_lookup(guc, desc_idx); > + if (unlikely(!ce)) > + return -EPROTO; > + > + if (unlikely(context_destroyed(ce) || > + (!context_pending_enable(ce) && > + !context_pending_disable(ce)))) { > + drm_dbg(&guc_to_gt(guc)->i915->drm, > + "Bad context sched_state 0x%x, 0x%x, desc_idx %u", > + atomic_read(&ce->guc_sched_state_no_lock), > + ce->guc_state.sched_state, desc_idx); > + return -EPROTO; > + } > + > + if (context_pending_enable(ce)) { > + clr_context_pending_enable(ce); > + } else if (context_pending_disable(ce)) { > + intel_context_sched_disable_unpin(ce); > + > + spin_lock_irqsave(&ce->guc_state.lock, flags); > + clr_context_pending_disable(ce); > + spin_unlock_irqrestore(&ce->guc_state.lock, flags); > + } > + > + intel_context_put(ce); > + > + return 0; > +} _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx