From patchwork Thu Sep 2 14:20:47 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 12471819 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 39A5EC4320A for ; Thu, 2 Sep 2021 14:21:12 +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 E332F61053 for ; Thu, 2 Sep 2021 14:21:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org E332F61053 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ffwll.ch Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0A3646E560; Thu, 2 Sep 2021 14:21:11 +0000 (UTC) Received: from mail-wm1-x330.google.com (mail-wm1-x330.google.com [IPv6:2a00:1450:4864:20::330]) by gabe.freedesktop.org (Postfix) with ESMTPS id 473066E593 for ; Thu, 2 Sep 2021 14:21:09 +0000 (UTC) Received: by mail-wm1-x330.google.com with SMTP id 79-20020a1c0452000000b002e6cf79e572so1591158wme.1 for ; Thu, 02 Sep 2021 07:21:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=ux0otQKkFIhr/QzCoIyfdoj8qLEcSwHP4PZjPx1SDPA=; b=GmC3l0SIdMeNjne5Uk2zC1bP6hyYwVk2VagtX+0PlQBCOc7cqIetweS/52DGepj7LA e6qHIg6QCPEv7VKLQu0Q4xATcbeAsWcdJR3MY/WxxqOCyNyxrmdXq9QQ78ElKr+ZqS4f Ay10seIzo6Xw1Q8LjK3JU6W2+t8MBpPgayS64= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=ux0otQKkFIhr/QzCoIyfdoj8qLEcSwHP4PZjPx1SDPA=; b=p0YQfArzW4BidrF/+6iMRPFwCxzRszx0rCFPPZvrmpguotUewBADY7R9i9v8GXVswL YMsprSWMciA6XwQNMvH0jdkipVk8Lgd7Ff8EQYSLd0HJknIMxIGQ64j3Jw8mcQNvPLz0 MwS8A8vYnHSvULI6RWOlDDu44SiumU0ktQj/f+UvSBtOSunbSm9nBTuhV/kAnmRbcm6g K1J6ap0Xo+GKzjT3fiR7rpEv7suV9IJ/LCiCvR18cLQxXfqL5a0uvEoeZKFVo2WwvaZq 3AtWDJps0RPY/QpSFOslRMFR+DBmTmU8Ft7fBim/sVbHvciZ4tgASOfucCUIExWLqGd0 enbQ== X-Gm-Message-State: AOAM532NZ1BIvuh5Ujrw+/+mAQgjsnOQltWBPXLwMeZAQHlj3mxjnzGF 2Lp3QZDuiA+R98O4hrl4G960ZIDNiBhcJg== X-Google-Smtp-Source: ABdhPJz+E4l437MOTIMiP8zWOjOwsHBZ4wPX0HjuuHeYspQFpcOUQoUr1QX8nZwLzQ86oD+eA7lnlA== X-Received: by 2002:a05:600c:2056:: with SMTP id p22mr3489538wmg.8.1630592467758; Thu, 02 Sep 2021 07:21:07 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id l2sm1841811wmi.1.2021.09.02.07.21.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 02 Sep 2021 07:21:07 -0700 (PDT) From: Daniel Vetter To: DRI Development Cc: Intel Graphics Development , Daniel Vetter , "Acked-by : Maarten Lankhorst" , Daniel Vetter , Jon Bloomfield , Chris Wilson , Joonas Lahtinen , =?utf-8?q?Thomas_Hellstr?= =?utf-8?q?=C3=B6m?= , Matthew Auld , Lionel Landwerlin , Dave Airlie , Jason Ekstrand Subject: [PATCH 01/11] drm/i915: Release i915_gem_context from a worker Date: Thu, 2 Sep 2021 16:20:47 +0200 Message-Id: <20210902142057.929669-1-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.33.0 MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" The only reason for this really is the i915_gem_engines->fence callback engines_notify(), which exists purely as a fairly funky reference counting scheme for that. Otherwise all other callers are from process context, and generally fairly benign locking context. Unfortunately untangling that requires some major surgery, and we have a few i915_gem_context reference counting bugs that need fixing, and they blow in the current hardirq calling context, so we need a stop-gap measure. Put a FIXME comment in when this should be removable again. v2: Fix mock_context(), noticed by intel-gfx-ci. Acked-by: Acked-by: Maarten Lankhorst Signed-off-by: Daniel Vetter Cc: Jon Bloomfield Cc: Chris Wilson Cc: Maarten Lankhorst Cc: Joonas Lahtinen Cc: Daniel Vetter Cc: "Thomas Hellström" Cc: Matthew Auld Cc: Lionel Landwerlin Cc: Dave Airlie Cc: Jason Ekstrand --- drivers/gpu/drm/i915/gem/i915_gem_context.c | 13 +++++++++++-- drivers/gpu/drm/i915/gem/i915_gem_context_types.h | 12 ++++++++++++ drivers/gpu/drm/i915/gem/selftests/mock_context.c | 1 + 3 files changed, 24 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 fd169cf2f75a..051bc357ff65 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_context.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c @@ -986,9 +986,10 @@ static struct i915_gem_engines *user_engines(struct i915_gem_context *ctx, return err; } -void i915_gem_context_release(struct kref *ref) +static void i915_gem_context_release_work(struct work_struct *work) { - struct i915_gem_context *ctx = container_of(ref, typeof(*ctx), ref); + struct i915_gem_context *ctx = container_of(work, typeof(*ctx), + release_work); trace_i915_context_free(ctx); GEM_BUG_ON(!i915_gem_context_is_closed(ctx)); @@ -1002,6 +1003,13 @@ void i915_gem_context_release(struct kref *ref) kfree_rcu(ctx, rcu); } +void i915_gem_context_release(struct kref *ref) +{ + struct i915_gem_context *ctx = container_of(ref, typeof(*ctx), ref); + + queue_work(ctx->i915->wq, &ctx->release_work); +} + static inline struct i915_gem_engines * __context_engines_static(const struct i915_gem_context *ctx) { @@ -1303,6 +1311,7 @@ i915_gem_create_context(struct drm_i915_private *i915, ctx->sched = pc->sched; mutex_init(&ctx->mutex); INIT_LIST_HEAD(&ctx->link); + INIT_WORK(&ctx->release_work, i915_gem_context_release_work); spin_lock_init(&ctx->stale.lock); INIT_LIST_HEAD(&ctx->stale.engines); 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 94c03a97cb77..0c38789bd4a8 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_context_types.h +++ b/drivers/gpu/drm/i915/gem/i915_gem_context_types.h @@ -288,6 +288,18 @@ struct i915_gem_context { */ struct kref ref; + /** + * @release_work: + * + * Work item for deferred cleanup, since i915_gem_context_put() tends to + * be called from hardirq context. + * + * FIXME: The only real reason for this is &i915_gem_engines.fence, all + * other callers are from process context and need at most some mild + * shuffling to pull the i915_gem_context_put() call out of a spinlock. + */ + struct work_struct release_work; + /** * @rcu: rcu_head for deferred freeing. */ diff --git a/drivers/gpu/drm/i915/gem/selftests/mock_context.c b/drivers/gpu/drm/i915/gem/selftests/mock_context.c index fee070df1c97..067d68a6fe4c 100644 --- a/drivers/gpu/drm/i915/gem/selftests/mock_context.c +++ b/drivers/gpu/drm/i915/gem/selftests/mock_context.c @@ -23,6 +23,7 @@ mock_context(struct drm_i915_private *i915, kref_init(&ctx->ref); INIT_LIST_HEAD(&ctx->link); ctx->i915 = i915; + INIT_WORK(&ctx->release_work, i915_gem_context_release_work); mutex_init(&ctx->mutex);