drm/i915/gvt: Use sched_lock to protect gvt scheduler logic.

The scheduler lock(gvt->sched_lock) is used to protect gvt
scheduler logic, including the gvt scheduler structure(gvt->scheduler
and per vgpu schedule data(vgpu->sched_data, vgpu->sched_ctl).

v9:
  - Change commit author since the patches are improved a lot compared
    with original version.
    Original author: Pei Zhang <pei.zhang@intel.com>
  - Rebase to latest gvt-staging.
v8:
  - Correct coding wqstyle.
  - Rebase to latest gvt-staging.
v7:
  - Remove gtt_lock since already proteced by gvt_lock and vgpu_lock.
v6:
  - Rebase to latest gvt-staging.
v5:
  - Rebase to latest gvt-staging.
v4:
  - Rebase to latest gvt-staging.
v3: update to latest code base

Signed-off-by: Pei Zhang <pei.zhang@intel.com>
Signed-off-by: Colin Xu <colin.xu@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
index 3600553c8b56..362e3d506d2d 100644
--- a/drivers/gpu/drm/i915/gvt/gvt.h
+++ b/drivers/gpu/drm/i915/gvt/gvt.h
@@ -177,6 +177,11 @@ struct intel_vgpu {
 	bool pv_notified;
 	bool failsafe;
 	unsigned int resetting_eng;
+
+	/* Both sched_data and sched_ctl can be seen a part of the global gvt
+	 * scheduler structure. So below 2 vgpu data are protected
+	 * by sched_lock, not vgpu_lock.
+	 */
 	void *sched_data;
 	struct vgpu_sched_ctl sched_ctl;
 
@@ -299,6 +304,9 @@ struct intel_gvt {
 	 * not yet protected by special locks(vgpu and scheduler lock).
 	 */
 	struct mutex lock;
+	/* scheduler scope lock, protect gvt and vgpu schedule related data */
+	struct mutex sched_lock;
+
 	struct drm_i915_private *dev_priv;
 	struct idr vgpu_idr;	/* vGPU IDR pool */