From patchwork Fri May 25 22:24:02 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 10428687 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 4F6AB602D6 for ; Fri, 25 May 2018 22:24:12 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 31787297ED for ; Fri, 25 May 2018 22:24:12 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 23F7C2981A; Fri, 25 May 2018 22:24:12 +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=-5.2 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, 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 8F717297ED for ; Fri, 25 May 2018 22:24:11 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 102F26E1E1; Fri, 25 May 2018 22:24:11 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from fireflyinternet.com (mail.fireflyinternet.com [109.228.58.192]) by gabe.freedesktop.org (Postfix) with ESMTPS id 3DB896E1E1 for ; Fri, 25 May 2018 22:24:08 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from haswell.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 11848415-1500050 for ; Fri, 25 May 2018 23:24:04 +0100 Received: by haswell.alporthouse.com (sSMTP sendmail emulation); Fri, 25 May 2018 23:24:03 +0100 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Fri, 25 May 2018 23:24:02 +0100 Message-Id: <20180525222403.28357-1-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.17.0 X-Originating-IP: 78.156.65.138 X-Country: code=GB country="United Kingdom" ip=78.156.65.138 Subject: [Intel-gfx] [CI 1/2] drm/i915: Switch to kernel context before idling at runtime 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: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP We can reduce our exposure to random neutrinos by resting on the kernel context having flushed out the user contexts to system memory and beyond. The corollary is that we then we require two passes through the idle handler to go to sleep, which on a truly idle system involves an extra pass through the slow and irregular retire work handler. Signed-off-by: Chris Wilson Reviewed-by: Mika Kuoppala --- drivers/gpu/drm/i915/i915_debugfs.c | 8 ++++++-- drivers/gpu/drm/i915/i915_gem.c | 29 ++++++++++++++++++++++++----- 2 files changed, 30 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index a8e7761cdc7d..594ee65a6c06 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -4226,8 +4226,12 @@ i915_drop_caches_set(void *data, u64 val) i915_gem_shrink_all(dev_priv); fs_reclaim_release(GFP_KERNEL); - if (val & DROP_IDLE) - drain_delayed_work(&dev_priv->gt.idle_work); + if (val & DROP_IDLE) { + do { + flush_delayed_work(&dev_priv->gt.retire_work); + drain_delayed_work(&dev_priv->gt.idle_work); + } while (READ_ONCE(dev_priv->gt.awake)); + } if (val & DROP_FREED) i915_gem_drain_freed_objects(dev_priv); diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 05f44ca35a06..c93f5dcb1d82 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -139,6 +139,8 @@ int i915_mutex_lock_interruptible(struct drm_device *dev) static u32 __i915_gem_park(struct drm_i915_private *i915) { + GEM_TRACE("\n"); + lockdep_assert_held(&i915->drm.struct_mutex); GEM_BUG_ON(i915->gt.active_requests); GEM_BUG_ON(!list_empty(&i915->gt.active_rings)); @@ -193,6 +195,8 @@ void i915_gem_park(struct drm_i915_private *i915) void i915_gem_unpark(struct drm_i915_private *i915) { + GEM_TRACE("\n"); + lockdep_assert_held(&i915->drm.struct_mutex); GEM_BUG_ON(!i915->gt.active_requests); @@ -3504,6 +3508,21 @@ i915_gem_idle_work_handler(struct work_struct *work) if (!READ_ONCE(dev_priv->gt.awake)) return; + /* + * Flush out the last user context, leaving only the pinned + * kernel context resident. When we are idling on the kernel_context, + * no more new requests (with a context switch) are emitted and we + * can finally rest. A consequence is that the idle work handler is + * always called at least twice before idling (and if the system is + * idle that implies a round trip through the retire worker). + */ + mutex_lock(&dev_priv->drm.struct_mutex); + i915_gem_switch_to_kernel_context(dev_priv); + mutex_unlock(&dev_priv->drm.struct_mutex); + + GEM_TRACE("active_requests=%d (after switch-to-kernel-context)\n", + READ_ONCE(dev_priv->gt.active_requests)); + /* * Wait for last execlists context complete, but bail out in case a * new request is submitted. As we don't trust the hardware, we @@ -4914,11 +4933,9 @@ static void assert_kernel_context_is_current(struct drm_i915_private *i915) void i915_gem_sanitize(struct drm_i915_private *i915) { - if (i915_terminally_wedged(&i915->gpu_error)) { - mutex_lock(&i915->drm.struct_mutex); + mutex_lock(&i915->drm.struct_mutex); + if (i915_terminally_wedged(&i915->gpu_error)) i915_gem_unset_wedged(i915); - mutex_unlock(&i915->drm.struct_mutex); - } /* * If we inherit context state from the BIOS or earlier occupants @@ -4930,6 +4947,9 @@ void i915_gem_sanitize(struct drm_i915_private *i915) */ if (INTEL_GEN(i915) >= 5 && intel_has_gpu_reset(i915)) WARN_ON(intel_gpu_reset(i915, ALL_ENGINES)); + + i915_gem_contexts_lost(i915); + mutex_unlock(&i915->drm.struct_mutex); } int i915_gem_suspend(struct drm_i915_private *dev_priv) @@ -4965,7 +4985,6 @@ int i915_gem_suspend(struct drm_i915_private *dev_priv) assert_kernel_context_is_current(dev_priv); } - i915_gem_contexts_lost(dev_priv); mutex_unlock(&dev->struct_mutex); intel_uc_suspend(dev_priv);