drm/xe/pf: Add _locked variants of the VF EQ config functions

In upcoming patches we will want to configure VF's execution
quantum (EQ) on all GTs under single lock to avoid potential
races in parallel GT configuration attempts.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Piotr Piórkowski <piotr.piorkowski@intel.com>
Link: https://patch.msgid.link/20251030222348.186658-4-michal.wajdeczko@intel.com

2 files changed, 53 insertions, 17 deletions

diff --git a/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c b/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c
index c0c0215c0703..f3e79a30d8ec 100644
--- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c
+++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c
@@ -1732,47 +1732,79 @@ static int pf_get_exec_quantum(struct xe_gt *gt, unsigned int vfid)
 }
 
 /**
- * xe_gt_sriov_pf_config_set_exec_quantum - Configure execution quantum for the VF.
+ * xe_gt_sriov_pf_config_set_exec_quantum_locked() - Configure PF/VF execution quantum.
  * @gt: the &xe_gt
- * @vfid: the VF identifier
+ * @vfid: the PF or VF identifier
  * @exec_quantum: requested execution quantum in milliseconds (0 is infinity)
  *
- * This function can only be called on PF.
+ * This function can only be called on PF with the master mutex hold.
+ * It will log the provisioned value or an error in case of the failure.
  *
  * Return: 0 on success or a negative error code on failure.
  */
-int xe_gt_sriov_pf_config_set_exec_quantum(struct xe_gt *gt, unsigned int vfid,
-					   u32 exec_quantum)
+int xe_gt_sriov_pf_config_set_exec_quantum_locked(struct xe_gt *gt, unsigned int vfid,
+						  u32 exec_quantum)
 {
 	int err;
 
-	mutex_lock(xe_gt_sriov_pf_master_mutex(gt));
+	lockdep_assert_held(xe_gt_sriov_pf_master_mutex(gt));
+
 	err = pf_provision_exec_quantum(gt, vfid, exec_quantum);
-	mutex_unlock(xe_gt_sriov_pf_master_mutex(gt));
 
 	return pf_config_set_u32_done(gt, vfid, exec_quantum,
-				      xe_gt_sriov_pf_config_get_exec_quantum(gt, vfid),
+				      pf_get_exec_quantum(gt, vfid),
 				      "execution quantum", exec_quantum_unit, err);
 }
 
 /**
- * xe_gt_sriov_pf_config_get_exec_quantum - Get VF's execution quantum.
+ * xe_gt_sriov_pf_config_set_exec_quantum() - Configure PF/VF execution quantum.
  * @gt: the &xe_gt
- * @vfid: the VF identifier
+ * @vfid: the PF or VF identifier
+ * @exec_quantum: requested execution quantum in milliseconds (0 is infinity)
  *
  * This function can only be called on PF.
+ * It will log the provisioned value or an error in case of the failure.
  *
- * Return: VF's (or PF's) execution quantum in milliseconds.
+ * Return: 0 on success or a negative error code on failure.
  */
-u32 xe_gt_sriov_pf_config_get_exec_quantum(struct xe_gt *gt, unsigned int vfid)
+int xe_gt_sriov_pf_config_set_exec_quantum(struct xe_gt *gt, unsigned int vfid,
+					   u32 exec_quantum)
 {
-	u32 exec_quantum;
+	guard(mutex)(xe_gt_sriov_pf_master_mutex(gt));
 
-	mutex_lock(xe_gt_sriov_pf_master_mutex(gt));
-	exec_quantum = pf_get_exec_quantum(gt, vfid);
-	mutex_unlock(xe_gt_sriov_pf_master_mutex(gt));
+	return xe_gt_sriov_pf_config_set_exec_quantum_locked(gt, vfid, exec_quantum);
+}
+
+/**
+ * xe_gt_sriov_pf_config_get_exec_quantum_locked() - Get PF/VF execution quantum.
+ * @gt: the &xe_gt
+ * @vfid: the PF or VF identifier
+ *
+ * This function can only be called on PF with the master mutex hold.
+ *
+ * Return: execution quantum in milliseconds (or 0 if infinity).
+ */
+u32 xe_gt_sriov_pf_config_get_exec_quantum_locked(struct xe_gt *gt, unsigned int vfid)
+{
+	lockdep_assert_held(xe_gt_sriov_pf_master_mutex(gt));
+
+	return pf_get_exec_quantum(gt, vfid);
+}
+
+/**
+ * xe_gt_sriov_pf_config_get_exec_quantum() - Get PF/VF execution quantum.
+ * @gt: the &xe_gt
+ * @vfid: the PF or VF identifier
+ *
+ * This function can only be called on PF.
+ *
+ * Return: execution quantum in milliseconds (or 0 if infinity).
+ */
+u32 xe_gt_sriov_pf_config_get_exec_quantum(struct xe_gt *gt, unsigned int vfid)
+{
+	guard(mutex)(xe_gt_sriov_pf_master_mutex(gt));
 
-	return exec_quantum;
+	return pf_get_exec_quantum(gt, vfid);
 }
 
 static const char *preempt_timeout_unit(u32 preempt_timeout)
diff --git a/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.h b/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.h
index 513e6512a575..b4beb5a97031 100644
--- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.h
+++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.h
@@ -40,6 +40,10 @@ int xe_gt_sriov_pf_config_bulk_set_lmem(struct xe_gt *gt, unsigned int vfid, uns
 u32 xe_gt_sriov_pf_config_get_exec_quantum(struct xe_gt *gt, unsigned int vfid);
 int xe_gt_sriov_pf_config_set_exec_quantum(struct xe_gt *gt, unsigned int vfid, u32 exec_quantum);
 
+u32 xe_gt_sriov_pf_config_get_exec_quantum_locked(struct xe_gt *gt, unsigned int vfid);
+int xe_gt_sriov_pf_config_set_exec_quantum_locked(struct xe_gt *gt, unsigned int vfid,
+						  u32 exec_quantum);
+
 u32 xe_gt_sriov_pf_config_get_preempt_timeout(struct xe_gt *gt, unsigned int vfid);
 int xe_gt_sriov_pf_config_set_preempt_timeout(struct xe_gt *gt, unsigned int vfid,
 					      u32 preempt_timeout);