From 8687b3ec852e89630bac650f15136811c7b4c1dc Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 7 Oct 2016 07:53:24 +0100 Subject: [PATCH] drm/i915: Distinguish last emitted request from last submitted request In order not to trigger hangcheck on a idle-but-waiting engine, we need to distinguish between the pending request queue and the actual execution queue. This is done later in "drm/i915: Enable multiple timelines" but for now we need a temporary fix to prevent blaming the wrong engine for a GPU hang. (Note that this causes a temporary subtle change in how we decide when to allow a waitboost to be re-awarded back to the waiter, the temporary effect is that if the wait is upon the most current execution the wait is given for free, instead of checking to see if the client stalled itself. This will be repaired in "drm/i915: Enable multiple timelines".) Fixes: 0a046a0e93d2 ("drm/i915: Nonblocking request submission") Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98104 Signed-off-by: Chris Wilson Cc: Joonas Lahtinen Cc: Mika Kuoppala Reviewed-by: Joonas Lahtinen Reviewed-by: Mika Kuoppala Link: http://patchwork.freedesktop.org/patch/msgid/20161007065327.24515-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_gem_request.c | 5 +++-- drivers/gpu/drm/i915/intel_ringbuffer.h | 1 + 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_request.c b/drivers/gpu/drm/i915/i915_gem_request.c index 40978bc12ceb..8832f8ec1583 100644 --- a/drivers/gpu/drm/i915/i915_gem_request.c +++ b/drivers/gpu/drm/i915/i915_gem_request.c @@ -328,6 +328,7 @@ submit_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify state) switch (state) { case FENCE_COMPLETE: + request->engine->last_submitted_seqno = request->fence.seqno; request->engine->submit_request(request); break; @@ -641,8 +642,8 @@ void __i915_add_request(struct drm_i915_gem_request *request, bool flush_caches) &request->submitq); request->emitted_jiffies = jiffies; - request->previous_seqno = engine->last_submitted_seqno; - engine->last_submitted_seqno = request->fence.seqno; + request->previous_seqno = engine->last_pending_seqno; + engine->last_pending_seqno = request->fence.seqno; i915_gem_active_set(&engine->last_request, request); list_add_tail(&request->link, &engine->request_list); list_add_tail(&request->ring_link, &ring->request_list); diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h index 498931f0b1f1..34954ca03a4a 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.h +++ b/drivers/gpu/drm/i915/intel_ringbuffer.h @@ -355,6 +355,7 @@ struct intel_engine_cs { * inspecting request list. */ u32 last_submitted_seqno; + u32 last_pending_seqno; /* An RCU guarded pointer to the last request. No reference is * held to the request, users must carefully acquire a reference to -- 2.20.1