From patchwork Mon Feb 26 16:37:59 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Micha=C5=82_Winiarski?= X-Patchwork-Id: 10242785 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id CDE2660208 for ; Mon, 26 Feb 2018 16:49:50 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BB88E2A194 for ; Mon, 26 Feb 2018 16:49:50 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AFFDB2A19C; Mon, 26 Feb 2018 16:49:50 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 147C72A194 for ; Mon, 26 Feb 2018 16:49:40 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 4795B6E4AA; Mon, 26 Feb 2018 16:49:39 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by gabe.freedesktop.org (Postfix) with ESMTPS id D3EBD6E4AA for ; Mon, 26 Feb 2018 16:49:37 +0000 (UTC) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 26 Feb 2018 08:49:37 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.47,397,1515484800"; d="scan'208";a="34249658" Received: from irsmsx102.ger.corp.intel.com ([163.33.3.155]) by orsmga001.jf.intel.com with ESMTP; 26 Feb 2018 08:49:36 -0800 Received: from localhost (172.28.172.64) by IRSMSX102.ger.corp.intel.com (163.33.3.155) with Microsoft SMTP Server (TLS) id 14.3.319.2; Mon, 26 Feb 2018 16:39:06 +0000 From: =?UTF-8?q?Micha=C5=82=20Winiarski?= To: Date: Mon, 26 Feb 2018 17:37:59 +0100 Message-ID: <20180226163800.21745-1-michal.winiarski@intel.com> X-Mailer: git-send-email 2.14.3 MIME-Version: 1.0 X-Originating-IP: [172.28.172.64] Subject: [Intel-gfx] [PATCH v2 1/2] drm/i915/guc: Fill preempt context once at init time X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mika Kuoppala Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP Since we're inhibiting context save of preempt context, we're no longer tracking the position of HEAD/TAIL. With GuC, we're adding a new breadcrumb for each preemption, which means that the HW will do more and more breadcrumb writes. Eventually the ring is filled, and we're submitting the preemption context with HEAD==TAIL==0, which won't result in breadcrumb write, but will trigger hangcheck instead. Instead of writing a new preempt breadcrumb for each preemption, let's just fill the ring once at init time (which also saves a couple of instructions in the tasklet). v2: Assert that context save restore is inhibited, don't assert on ring alignment. (Chris) Fixes: 517aaffe0c1b ("drm/i915/execlists: Inhibit context save/restore for the fake preempt context") Signed-off-by: Michał Winiarski Cc: Chris Wilson Cc: Daniele Ceraolo Spurio Cc: Michel Thierry Cc: Mika Kuoppala Cc: Tvrtko Ursulin Reviewed-by: Chris Wilson --- drivers/gpu/drm/i915/intel_guc_submission.c | 86 ++++++++++++++++++++--------- 1 file changed, 59 insertions(+), 27 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_guc_submission.c b/drivers/gpu/drm/i915/intel_guc_submission.c index 586dde579903..3805839f567b 100644 --- a/drivers/gpu/drm/i915/intel_guc_submission.c +++ b/drivers/gpu/drm/i915/intel_guc_submission.c @@ -26,8 +26,13 @@ #include #include "intel_guc_submission.h" +#include "intel_lrc_reg.h" #include "i915_drv.h" +#define GUC_PREEMPT_FINISHED 0x1 +#define GUC_PREEMPT_BREADCRUMB_DWORDS 0x8 +#define GUC_PREEMPT_BREADCRUMB_BYTES (sizeof(u32) * GUC_PREEMPT_BREADCRUMB_DWORDS) + /** * DOC: GuC-based command submission * @@ -535,8 +540,6 @@ static void flush_ggtt_writes(struct i915_vma *vma) POSTING_READ_FW(GUC_STATUS); } -#define GUC_PREEMPT_FINISHED 0x1 -#define GUC_PREEMPT_BREADCRUMB_DWORDS 0x8 static void inject_preempt_context(struct work_struct *work) { struct guc_preempt_work *preempt_work = @@ -546,37 +549,17 @@ static void inject_preempt_context(struct work_struct *work) preempt_work[engine->id]); struct intel_guc_client *client = guc->preempt_client; struct guc_stage_desc *stage_desc = __get_stage_desc(client); - struct intel_ring *ring = client->owner->engine[engine->id].ring; u32 ctx_desc = lower_32_bits(intel_lr_context_descriptor(client->owner, engine)); - u32 *cs = ring->vaddr + ring->tail; u32 data[7]; - if (engine->id == RCS) { - cs = gen8_emit_ggtt_write_rcs(cs, GUC_PREEMPT_FINISHED, - intel_hws_preempt_done_address(engine)); - } else { - cs = gen8_emit_ggtt_write(cs, GUC_PREEMPT_FINISHED, - intel_hws_preempt_done_address(engine)); - *cs++ = MI_NOOP; - *cs++ = MI_NOOP; - } - *cs++ = MI_USER_INTERRUPT; - *cs++ = MI_NOOP; - - GEM_BUG_ON(!IS_ALIGNED(ring->size, - GUC_PREEMPT_BREADCRUMB_DWORDS * sizeof(u32))); - GEM_BUG_ON((void *)cs - (ring->vaddr + ring->tail) != - GUC_PREEMPT_BREADCRUMB_DWORDS * sizeof(u32)); - - ring->tail += GUC_PREEMPT_BREADCRUMB_DWORDS * sizeof(u32); - ring->tail &= (ring->size - 1); - - flush_ggtt_writes(ring->vma); - + /* + * The ring should containt commands writing GUC_PREEMPT_FINISHED to + * HWSP at client initialization time. + */ spin_lock_irq(&client->wq_lock); guc_wq_item_append(client, engine->guc_id, ctx_desc, - ring->tail / sizeof(u64), 0); + GUC_PREEMPT_BREADCRUMB_BYTES / sizeof(u64), 0); spin_unlock_irq(&client->wq_lock); /* @@ -972,6 +955,53 @@ static void guc_client_free(struct intel_guc_client *client) kfree(client); } +static void guc_fill_preempt_context(struct intel_guc *guc) +{ + struct drm_i915_private *dev_priv = guc_to_i915(guc); + struct intel_guc_client *client = guc->preempt_client; + struct intel_engine_cs *engine; + enum intel_engine_id id; + u32 *cs; + + for_each_engine(engine, dev_priv, id) { + struct intel_context *ce = &client->owner->engine[id]; + + GEM_BUG_ON(!ce->pin_count); + + /* + * We rely on this context image *not* being saved after + * preemption. This ensures that the RING_HEAD / RING_TAIL + * remaing pointing at initial values forever. + */ + GEM_BUG_ON((ce->lrc_reg_state[CTX_CONTEXT_CONTROL + 1] & + _MASKED_BIT_ENABLE( + CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT | + CTX_CTRL_ENGINE_CTX_SAVE_INHIBIT)) != + _MASKED_BIT_ENABLE( + CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT | + CTX_CTRL_ENGINE_CTX_SAVE_INHIBIT)); + + cs = ce->ring->vaddr; + + if (id == RCS) { + cs = gen8_emit_ggtt_write_rcs(cs, GUC_PREEMPT_FINISHED, + intel_hws_preempt_done_address(engine)); + } else { + cs = gen8_emit_ggtt_write(cs, GUC_PREEMPT_FINISHED, + intel_hws_preempt_done_address(engine)); + *cs++ = MI_NOOP; + *cs++ = MI_NOOP; + } + *cs++ = MI_USER_INTERRUPT; + *cs++ = MI_NOOP; + + GEM_BUG_ON((void *)cs - ce->ring->vaddr != + GUC_PREEMPT_BREADCRUMB_BYTES); + + flush_ggtt_writes(ce->ring->vma); + } +} + static int guc_clients_create(struct intel_guc *guc) { struct drm_i915_private *dev_priv = guc_to_i915(guc); @@ -1002,6 +1032,8 @@ static int guc_clients_create(struct intel_guc *guc) return PTR_ERR(client); } guc->preempt_client = client; + + guc_fill_preempt_context(guc); } return 0;