drm/amdgpu: Add enforce_isolation sysfs attribute

This commit adds a new sysfs attribute 'enforce_isolation' to control
the 'enforce_isolation' setting per GPU. The attribute can be read and
written, and accepts values 0 (disabled) and 1 (enabled).

When 'enforce_isolation' is enabled, reserved VMIDs are allocated for
each ring. When it's disabled, the reserved VMIDs are freed.

The set function locks a mutex before changing the 'enforce_isolation'
flag and the VMIDs, and unlocks it afterwards. This ensures that these
operations are atomic and prevents race conditions and other concurrency
issues.

Cc: Christian König <[email protected]>
Cc: Alex Deucher <[email protected]>
Signed-off-by: Srinivasan Shanmugam <[email protected]>
Suggested-by: Alex Deucher <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index e623af740aa3..2f1bc02309fe 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -4065,6 +4065,8 @@ int amdgpu_device_init(struct amdgpu_device *adev,
 	mutex_init(&adev->pm.stable_pstate_ctx_lock);
 	mutex_init(&adev->benchmark_mutex);
 	mutex_init(&adev->gfx.reset_sem_mutex);
+	/* Initialize the mutex for cleaner shader isolation between GFX and compute processes */
+	mutex_init(&adev->enforce_isolation_mutex);
 
 	amdgpu_device_init_apu_flags(adev);