[18/32] PCI: pciehp: Drop enable/disable lock

Commit Message

Lukas Wunner June 16, 2018, 7:25 p.m. UTC

Previously slot enablement and disablement could happen concurrently.
But now it's under the exclusive control of the IRQ thread, rendering
the locking obsolete.  Drop it.

Signed-off-by: Lukas Wunner <[e-mail]>
---
 drivers/pci/hotplug/pciehp.h      |  3 ---
 drivers/pci/hotplug/pciehp_ctrl.c | 11 -----------
 drivers/pci/hotplug/pciehp_hpc.c  |  1 -
 3 files changed, 15 deletions(-)

Patch

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index ed42dde5f9ac..5417180c3aff 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -67,8 +67,6 @@  do {									\
  *	an Attention Button press
  * @lock: protects reads and writes of @state;
  *	protects scheduling, execution and cancellation of @work
- * @hotplug_lock: serializes calls to pciehp_enable_slot() and
- *	pciehp_disable_slot()
  */
 struct slot {
 	u8 state;
@@ -76,7 +74,6 @@  struct slot {
 	struct hotplug_slot *hotplug_slot;
 	struct delayed_work work;
 	struct mutex lock;
-	struct mutex hotplug_lock;
 };
 
 /**
diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c
index 70bad847a450..8ba937599fb3 100644
--- a/drivers/pci/hotplug/pciehp_ctrl.c
+++ b/drivers/pci/hotplug/pciehp_ctrl.c
@@ -277,9 +277,6 @@  void pciehp_handle_presence_change(struct slot *slot)
 	}
 }
 
-/*
- * Note: This function must be called with slot->hotplug_lock held
- */
 static int __pciehp_enable_slot(struct slot *p_slot)
 {
 	u8 getstatus = 0;
@@ -316,10 +313,7 @@  int pciehp_enable_slot(struct slot *slot)
 	struct controller *ctrl = slot->ctrl;
 	int ret;
 
-	mutex_lock(&slot->hotplug_lock);
 	ret = __pciehp_enable_slot(slot);
-	mutex_unlock(&slot->hotplug_lock);
-
 	if (ret && ATTN_BUTTN(ctrl))
 		pciehp_green_led_off(slot); /* may be blinking */
 
@@ -330,9 +324,6 @@  int pciehp_enable_slot(struct slot *slot)
 	return ret;
 }
 
-/*
- * Note: This function must be called with slot->hotplug_lock held
- */
 static int __pciehp_disable_slot(struct slot *p_slot)
 {
 	u8 getstatus = 0;
@@ -355,9 +346,7 @@  int pciehp_disable_slot(struct slot *slot)
 {
 	int ret;
 
-	mutex_lock(&slot->hotplug_lock);
 	ret = __pciehp_disable_slot(slot);
-	mutex_unlock(&slot->hotplug_lock);
 
 	mutex_lock(&slot->lock);
 	slot->state = OFF_STATE;
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index 9aea0bdbb019..c795d32dbb73 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -781,7 +781,6 @@  static int pcie_init_slot(struct controller *ctrl)
 
 	slot->ctrl = ctrl;
 	mutex_init(&slot->lock);
-	mutex_init(&slot->hotplug_lock);
 	INIT_DELAYED_WORK(&slot->work, pciehp_queue_pushbutton_work);
 	ctrl->slot = slot;
 	return 0;