[PATCH] drm/amdgpu: Handle the GPU recovery failure in SRIOV environment.

[Surbhi Kakarya]

This patch handles the GPU recovery faliure in sriov environment by
retrying the reset if the first reset fails. To determine the condition of retry, a
new function amdgpu_is_retry_sriov_reset() is added which returns true if failure is due
to ETIMEDOUT, EINVAL or EBUSY, otherwise return false. MAX_RETRY_LIMIT is used to
limit the retry to 2.

It also handles the return status in Post Asic Reset by updating the return code
with asic_reset_res and eventually return the return code in amdgpu_job_timedout().

Signed-off-by: Surbhi Kakarya <Surbhi.Kakarya at amd.com>
Change-Id: Ib2e408819b4780e6963e1dc078c3410cd512e6e8
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 47 ++++++++++++++++++++--
 drivers/gpu/drm/amd/amdgpu/amdgpu_job.c    |  6 ++-
 2 files changed, 49 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 53af2623c58f..f50c18cb38c8 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -89,6 +89,7 @@ MODULE_FIRMWARE("amdgpu/vangogh_gpu_info.bin");
 MODULE_FIRMWARE("amdgpu/yellow_carp_gpu_info.bin");
 
 #define AMDGPU_RESUME_MS		2000
+#define MAX_RETRY_LIMIT		2
 
 const char *amdgpu_asic_name[] = {
 	"TAHITI",
@@ -5026,11 +5027,27 @@ static int amdgpu_device_suspend_display_audio(struct amdgpu_device *adev)
 	return 0;
 }
 
+/**
+ * amdgpu_is_retry_sriov_reset - check if we should retry sriov reset
+ *
+ * Check amdgpu_is_retry_sriov_reset and return status to see if we should retry reset.
+ */
+static bool amdgpu_is_retry_sriov_reset(int r)
+{
+
+        if(r == -EBUSY || r == -ETIMEDOUT || r == -EINVAL)
+                return true;
+        else
+                return false;
+
+}
+
 static void amdgpu_device_recheck_guilty_jobs(
 	struct amdgpu_device *adev, struct list_head *device_list_handle,
 	struct amdgpu_reset_context *reset_context)
 {
 	int i, r = 0;
+	int retry_limit = 0;
 
 	for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
 		struct amdgpu_ring *ring = adev->rings[i];
@@ -5064,8 +5081,18 @@ static void amdgpu_device_recheck_guilty_jobs(
 			if (amdgpu_sriov_vf(adev)) {
 				amdgpu_virt_fini_data_exchange(adev);
 				r = amdgpu_device_reset_sriov(adev, false);
-				if (r)
+				if (r) {
 					adev->asic_reset_res = r;
+					if (amdgpu_is_retry_sriov_reset(r)) {
+						adev->asic_reset_res = 0;
+						if (retry_limit < MAX_RETRY_LIMIT) {
+							retry_limit++;
+							goto retry;
+						}
+						else
+							DRM_ERROR("GPU reset retry is beyond the retry limit\n");
+					}
+				}
 			} else {
 				clear_bit(AMDGPU_SKIP_HW_RESET,
 					  &reset_context->flags);
@@ -5122,6 +5149,7 @@ int amdgpu_device_gpu_recover(struct amdgpu_device *adev,
 	bool locked = false;
 	int tmp_vram_lost_counter;
 	struct amdgpu_reset_context reset_context;
+	int retry_limit = 0;
 
 	memset(&reset_context, 0, sizeof(reset_context));
 
@@ -5299,8 +5327,18 @@ int amdgpu_device_gpu_recover(struct amdgpu_device *adev,
 	/* Host driver will handle XGMI hive reset for SRIOV */
 	if (amdgpu_sriov_vf(adev)) {
 		r = amdgpu_device_reset_sriov(adev, job ? false : true);
-		if (r)
-			adev->asic_reset_res = r;
+                if (r) {
+                        adev->asic_reset_res = r;
+                        if (amdgpu_is_retry_sriov_reset(r)) {
+				adev->asic_reset_res = 0;
+				if (retry_limit < MAX_RETRY_LIMIT) {
+					retry_limit++;
+					goto retry;
+				}
+				else
+					DRM_ERROR("GPU reset retry is beyond the retry limit\n");
+                        }
+                }
 	} else {
 		r = amdgpu_do_asic_reset(device_list_handle, &reset_context);
 		if (r && r == -EAGAIN)
@@ -5341,6 +5379,9 @@ int amdgpu_device_gpu_recover(struct amdgpu_device *adev,
 			drm_helper_resume_force_mode(adev_to_drm(tmp_adev));
 		}
 
+		if (tmp_adev->asic_reset_res)
+			r = tmp_adev->asic_reset_res;
+
 		tmp_adev->asic_reset_res = 0;
 
 		if (r) {
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
index e0730ea56a8c..1f0fb21ac15a 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
@@ -37,6 +37,7 @@ static enum drm_gpu_sched_stat amdgpu_job_timedout(struct drm_sched_job *s_job)
 	struct amdgpu_task_info ti;
 	struct amdgpu_device *adev = ring->adev;
 	int idx;
+	int r = 0;
 
 	if (!drm_dev_enter(adev_to_drm(adev), &idx)) {
 		DRM_INFO("%s - device unplugged skipping recovery on scheduler:%s",
@@ -63,7 +64,10 @@ static enum drm_gpu_sched_stat amdgpu_job_timedout(struct drm_sched_job *s_job)
 		  ti.process_name, ti.tgid, ti.task_name, ti.pid);
 
 	if (amdgpu_device_should_recover_gpu(ring->adev)) {
-		amdgpu_device_gpu_recover(ring->adev, job);
+		r = amdgpu_device_gpu_recover(ring->adev, job);
+		if (r)
+			DRM_ERROR("GPU Recovery Failed: %d\n",r);
+
 	} else {
 		drm_sched_suspend_timeout(&ring->sched);
 		if (amdgpu_sriov_vf(adev))
-- 
2.25.1