From 70cd14761d8aeb5db19a410a0a85155e88bb8ad0 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Mon, 28 Nov 2016 14:36:49 +0000 Subject: [PATCH] Revert "drm/i915/execlists: Use a local lock for dfs_link access" This reverts commit 27745e829a5c ("drm/i915/execlists: Use a local lock for dfs_link access") as the struct_mutex was required to prevent concurrent retiring and freeing, now restored in the previous patch. Signed-off-by: Chris Wilson Cc: David Weinehall Cc: Tvrtko Ursulin Link: http://patchwork.freedesktop.org/patch/msgid/20161128143649.4289-2-chris@chris-wilson.co.uk Reviewed-by: Tvrtko Ursulin --- drivers/gpu/drm/i915/intel_lrc.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c index 0a09024d6ca3..b2c0d509e191 100644 --- a/drivers/gpu/drm/i915/intel_lrc.c +++ b/drivers/gpu/drm/i915/intel_lrc.c @@ -695,7 +695,6 @@ pt_lock_engine(struct i915_priotree *pt, struct intel_engine_cs *locked) static void execlists_schedule(struct drm_i915_gem_request *request, int prio) { - static DEFINE_MUTEX(lock); struct intel_engine_cs *engine = NULL; struct i915_dependency *dep, *p; struct i915_dependency stack; @@ -704,8 +703,8 @@ static void execlists_schedule(struct drm_i915_gem_request *request, int prio) if (prio <= READ_ONCE(request->priotree.priority)) return; - /* Need global lock to use the temporary link inside i915_dependency */ - mutex_lock(&lock); + /* Need BKL in order to use the temporary link inside i915_dependency */ + lockdep_assert_held(&request->i915->drm.struct_mutex); stack.signaler = &request->priotree; list_add(&stack.dfs_link, &dfs); @@ -772,8 +771,6 @@ static void execlists_schedule(struct drm_i915_gem_request *request, int prio) if (engine) spin_unlock_irq(&engine->timeline->lock); - mutex_unlock(&lock); - /* XXX Do we need to preempt to make room for us and our deps? */ }