Commit 7c567bbf authored by Michal Wajdeczko's avatar Michal Wajdeczko Committed by Daniel Vetter
Browse files

drm/i915/guc: Start protecting access to CTB descriptors 



We want to stop using guc.send_mutex while sending CTB messages
so we have to start protecting access to CTB send descriptor.

For completeness protect also CTB receive descriptor.

Add spinlock to struct intel_guc_ct_buffer and start using it.

Signed-off-by: default avatarMichal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: default avatarMatthew Brost <matthew.brost@intel.com>
Reviewed-by: default avatarMatthew Brost <matthew.brost@intel.com>
Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210603051630.2635-15-matthew.brost@intel.com
parent df12d1c3

drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c

+12 −2
Original line number Diff line number Diff line
@@ -89,6 +89,8 @@ static void ct_incoming_request_worker_func(struct work_struct *w); 
 */

void intel_guc_ct_init_early(struct intel_guc_ct *ct)

{

	spin_lock_init(&ct->ctbs.send.lock);

	spin_lock_init(&ct->ctbs.recv.lock);

	spin_lock_init(&ct->requests.lock);

	INIT_LIST_HEAD(&ct->requests.pending);

	INIT_LIST_HEAD(&ct->requests.incoming);
@@ -473,17 +475,22 @@ static int ct_send(struct intel_guc_ct *ct, 
	GEM_BUG_ON(len & ~GUC_CT_MSG_LEN_MASK);

	GEM_BUG_ON(!response_buf && response_buf_size);



	spin_lock_irqsave(&ct->ctbs.send.lock, flags);



	fence = ct_get_next_fence(ct);

	request.fence = fence;

	request.status = 0;

	request.response_len = response_buf_size;

	request.response_buf = response_buf;



	spin_lock_irqsave(&ct->requests.lock, flags);

	spin_lock(&ct->requests.lock);

	list_add_tail(&request.link, &ct->requests.pending);

	spin_unlock_irqrestore(&ct->requests.lock, flags);

	spin_unlock(&ct->requests.lock);



	err = ct_write(ct, action, len, fence);



	spin_unlock_irqrestore(&ct->ctbs.send.lock, flags);



	if (unlikely(err))

		goto unlink;
@@ -819,6 +826,7 @@ static int ct_handle_request(struct intel_guc_ct *ct, const u32 *msg) 
void intel_guc_ct_event_handler(struct intel_guc_ct *ct)

{

	u32 msg[GUC_CT_MSG_LEN_MASK + 1]; /* one extra dw for the header */

	unsigned long flags;

	int err = 0;



	if (unlikely(!ct->enabled)) {
@@ -827,7 +835,9 @@ void intel_guc_ct_event_handler(struct intel_guc_ct *ct) 
	}



	do {

		spin_lock_irqsave(&ct->ctbs.recv.lock, flags);

		err = ct_read(ct, msg);

		spin_unlock_irqrestore(&ct->ctbs.recv.lock, flags);

		if (err)

			break;

drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h

+2 −0
Original line number Diff line number Diff line
@@ -27,11 +27,13 @@ struct intel_guc; 
 * record (command transport buffer descriptor) and the actual buffer which

 * holds the commands.

 *

 * @lock: protects access to the commands buffer and buffer descriptor

 * @desc: pointer to the buffer descriptor

 * @cmds: pointer to the commands buffer

 * @size: size of the commands buffer

 */

struct intel_guc_ct_buffer {

	spinlock_t lock;

	struct guc_ct_buffer_desc *desc;

	u32 *cmds;

	u32 size;