From patchwork Fri Aug 13 20:30:23 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 12436113 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=-16.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 E139AC4338F for ; Fri, 13 Aug 2021 20:30:51 +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 5DC4A60560 for ; Fri, 13 Aug 2021 20:30:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 5DC4A60560 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 6D3A76E8D5; Fri, 13 Aug 2021 20:30:44 +0000 (UTC) Received: from mail-ed1-x533.google.com (mail-ed1-x533.google.com [IPv6:2a00:1450:4864:20::533]) by gabe.freedesktop.org (Postfix) with ESMTPS id 95BA26E8CF for ; Fri, 13 Aug 2021 20:30:42 +0000 (UTC) Received: by mail-ed1-x533.google.com with SMTP id by4so17265049edb.0 for ; Fri, 13 Aug 2021 13:30:42 -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=bs10p23sJWJDZZNCcTGppQo97upc2uTkLgGG89DVdpg=; b=lJKNKsFyyvM8zMfy4wA0T+fIu2tMRlj6ys+Bf+FsZsPSjQbLhLKGrLJXrKhc/wIZ/g s5J/n9o5G0Qb0qrLXI0/OBk4ZfatHjDW7SQN7/qYyWx28ZRv1DctU7HGeZ+NoyfzBOie HLLE2sWC5m+kE9jEa9vdsGgiTvK1N+xQwmJ7A= 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=bs10p23sJWJDZZNCcTGppQo97upc2uTkLgGG89DVdpg=; b=WE6HbLKC1qc+L8u2xYl5SRpuWXps2Q7Gh1L63mzV3GzauSHB32b6FxB9wNT0DgHxzf Idr2EcpfOTe1czJvOrVBs7Pl7zU8QeOfweSBPU/7bPTRKqL48AvAf6X+New0EW2Ok7C1 gQ9u7hmh/6z5wovtAQGibUBzh10vcndnAAviPd1J/doQyFSViuJvPhBtPUqD7V23JJt0 Cdgv26ueE7bdKrGYbc4yZQin5sdzzStdti402Smzk/4t0rfdIAjERjcMbEgt106XhcO9 0Xdpz5FTyjwkZbaQoXQ3ftrsTE444Vc6msonFl/NfyFOzpQa0zX6OwyMVL6fNGwJk258 6z7A== X-Gm-Message-State: AOAM532Y81cbyjzbdzLv1CdNa0c3MnMVRuFkleiCWk7gmmdJqH66V8HV nAgnj2fDG07r//apiAWGxNS0ZA== X-Google-Smtp-Source: ABdhPJxA4fCN9NdWYxER76qUyb+wPQxhwzQPLAHzBZ1m+WoT5XfAdOLM1dlaTJkHSyazHnCzVRQhAw== X-Received: by 2002:aa7:c795:: with SMTP id n21mr5272461eds.182.1628886641125; Fri, 13 Aug 2021 13:30:41 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id y17sm1347027edv.51.2021.08.13.13.30.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 13 Aug 2021 13:30:40 -0700 (PDT) From: Daniel Vetter To: DRI Development Cc: Intel Graphics Development , Daniel Vetter , Daniel Vetter , Jon Bloomfield , Chris Wilson , Maarten Lankhorst , Joonas Lahtinen , =?utf-8?q?Thomas_Hellstr?= =?utf-8?q?=C3=B6m?= , Matthew Auld , Lionel Landwerlin , Dave Airlie , Jason Ekstrand Date: Fri, 13 Aug 2021 22:30:23 +0200 Message-Id: <20210813203033.3179400-1-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.32.0 MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH 01/11] drm/i915: Release i915_gem_context from a worker 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: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" 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. 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 ++++++++++++ 2 files changed, 23 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. */