[Linux-kernel-mentees] [RFC PATCH v5 15/23] PCI: Replace pcie_link_state based device list with a pci_dev one

[Saheed O. Bolarinwa]

 - Replace existing pcie_link_state based device list with one
   based on struct pci_dev one.
 - Remove initialisation and declaration of existing list.
 - Replace pcie_link_state.sibling with pci_dev.sibling.
 - Remove pcie_link_state.sibling.

Signed-off-by: Saheed O. Bolarinwa <refactormyself at gmail.com>
---
 drivers/pci/pcie/aspm.c | 27 +++++++++++----------------
 1 file changed, 11 insertions(+), 16 deletions(-)

diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 6f73eb2ca0bd..9ca06f00e98d 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -46,7 +46,6 @@ struct pcie_link_state {
 	struct pci_dev *downstream;	/* Downstream component, function 0 */
 	struct pcie_link_state *root;	/* pointer to the root port link */
 	struct pcie_link_state *parent;	/* pointer to the parent Link state */
-	struct list_head sibling;	/* node in link_list */
 
 	/* ASPM state */
 	u32 aspm_support:7;		/* Supported ASPM state */
@@ -74,7 +73,6 @@ struct pcie_link_state {
 static int aspm_disabled, aspm_force;
 static bool aspm_support_enabled = true;
 static DEFINE_MUTEX(aspm_lock);
-static LIST_HEAD(link_list);
 static LIST_HEAD(pdev_link_list);
 
 #define POLICY_DEFAULT 0	/* BIOS default setting */
@@ -856,7 +854,6 @@ static int alloc_pcie_link_state(struct pci_dev *pdev)
 	if (!link)
 		return -1;
 
-	INIT_LIST_HEAD(&link->sibling);
 	INIT_LIST_HEAD(&pdev->sibling);
 	link->pdev = pdev;
 	link->downstream = pci_function_0(pdev->subordinate);
@@ -889,7 +886,6 @@ static int alloc_pcie_link_state(struct pci_dev *pdev)
 		pdev->root = pdev->parent->root;
 	}
 
-	list_add(&link->sibling, &link_list);
 	list_add(&pdev->sibling, &pdev_link_list);
 	pdev->link_state = link;
 	return 0;
@@ -975,20 +971,19 @@ void pcie_aspm_init_link_state(struct pci_dev *pdev)
 }
 
 /* Recheck latencies and update aspm_capable for links under the root */
-static void pcie_update_aspm_capable(struct pci_dev *root_pdev)
+static void pcie_update_aspm_capable(struct pci_dev *root)
 {
-	struct pcie_link_state *root = root_pdev->link_state;
-	struct pcie_link_state *link;
+	struct pci_dev *link;
+
 	BUG_ON(root->parent);
-	list_for_each_entry(link, &link_list, sibling) {
+	list_for_each_entry(link, &pdev_link_list, sibling) {
 		if (link->root != root)
 			continue;
 		link->aspm_capable = link->aspm_support;
-		link->pdev->aspm_capable = link->aspm_support;
 	}
-	list_for_each_entry(link, &link_list, sibling) {
+	list_for_each_entry(link, &pdev_link_list, sibling) {
 		struct pci_dev *child;
-		struct pci_bus *linkbus = link->pdev->subordinate;
+		struct pci_bus *linkbus = link->subordinate;
 		if (link->root != root)
 			continue;
 		list_for_each_entry(child, &linkbus->devices, bus_list) {
@@ -1024,7 +1019,7 @@ void pcie_aspm_exit_link_state(struct pci_dev *pdev)
 
 	/* All functions are removed, so just disable ASPM for the link */
 	pcie_config_aspm_link(parent, 0);
-	list_del(&link->sibling);
+	list_del(&link->pdev->sibling);
 	/* Clock PM is for endpoint device */
 	free_link_state(parent);
 
@@ -1177,7 +1172,7 @@ static int pcie_aspm_set_policy(const char *val,
 				const struct kernel_param *kp)
 {
 	int i;
-	struct pcie_link_state *link;
+	struct pci_dev *link;
 
 	if (aspm_disabled)
 		return -EPERM;
@@ -1190,9 +1185,9 @@ static int pcie_aspm_set_policy(const char *val,
 	down_read(&pci_bus_sem);
 	mutex_lock(&aspm_lock);
 	aspm_policy = i;
-	list_for_each_entry(link, &link_list, sibling) {
-		pcie_config_aspm_link(link->pdev, policy_to_aspm_state(link->pdev));
-		pcie_set_clkpm(link->pdev, policy_to_clkpm_state(link->pdev));
+	list_for_each_entry(link, &pdev_link_list, sibling) {
+		pcie_config_aspm_link(link, policy_to_aspm_state(link));
+		pcie_set_clkpm(link, policy_to_clkpm_state(link));
 	}
 	mutex_unlock(&aspm_lock);
 	up_read(&pci_bus_sem);
-- 
2.18.4