From 44c22f3f1a0a1a24b7d9b0afdd77bbb949e05ba1 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Tue, 20 Aug 2019 09:09:07 +0100 Subject: [PATCH] drm/i915: Serialize insertion into the file->mm.request_list Currently, we remove the from per-file request list for throttling and retirement under a dedicated spinlock, but insertion is governed by struct_mutex. This needs to be the same lock so that the retirement/insertion of neighbouring requests (at the tail) doesn't break the list. Signed-off-by: Chris Wilson Cc: Matthew Auld Reviewed-by: Matthew Auld Link: https://patchwork.freedesktop.org/patch/msgid/20190820080907.4665-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c | 9 +++++++-- drivers/gpu/drm/i915/i915_request.c | 6 +++--- 2 files changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c index 577bd7c72e65..5fb358be7c47 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c @@ -2005,8 +2005,13 @@ err: static void add_to_client(struct i915_request *rq, struct drm_file *file) { - rq->file_priv = file->driver_priv; - list_add_tail(&rq->client_link, &rq->file_priv->mm.request_list); + struct drm_i915_file_private *file_priv = file->driver_priv; + + rq->file_priv = file_priv; + + spin_lock(&file_priv->mm.lock); + list_add_tail(&rq->client_link, &file_priv->mm.request_list); + spin_unlock(&file_priv->mm.lock); } static int eb_submit(struct i915_execbuffer *eb) diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c index ae3a60a0c392..934ea9592908 100644 --- a/drivers/gpu/drm/i915/i915_request.c +++ b/drivers/gpu/drm/i915/i915_request.c @@ -165,11 +165,11 @@ static void __notify_execute_cb(struct i915_request *rq) } static inline void -i915_request_remove_from_client(struct i915_request *request) +remove_from_client(struct i915_request *request) { struct drm_i915_file_private *file_priv; - file_priv = request->file_priv; + file_priv = READ_ONCE(request->file_priv); if (!file_priv) return; @@ -282,7 +282,7 @@ static bool i915_request_retire(struct i915_request *rq) local_irq_enable(); - i915_request_remove_from_client(rq); + remove_from_client(rq); list_del(&rq->link); intel_context_exit(rq->hw_context);