[PATCH v4 5/7] drivers/pci/hotplug: Remove likely() and unlikely() in powernv driver
Gavin Shan
gwshan at linux.vnet.ibm.com
Thu Sep 29 15:52:03 AEST 2016
This removes likely() and unlikely() in pnv_php.c as the code isn't
running in hot path. Those macros to affect CPU's branch stream don't
help a lot for performance. I used them to identify the cases are
likely or unlikely to happen. No logical changes introduced.
Signed-off-by: Gavin Shan <gwshan at linux.vnet.ibm.com>
---
drivers/pci/hotplug/pnv_php.c | 56 +++++++++++++++++++++----------------------
1 file changed, 28 insertions(+), 28 deletions(-)
diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c
index e6245b0..182f218 100644
--- a/drivers/pci/hotplug/pnv_php.c
+++ b/drivers/pci/hotplug/pnv_php.c
@@ -122,7 +122,7 @@ static void pnv_php_detach_device_nodes(struct device_node *parent)
of_node_put(dn);
refcount = atomic_read(&dn->kobj.kref.refcount);
- if (unlikely(refcount != 1))
+ if (refcount != 1)
pr_warn("Invalid refcount %d on <%s>\n",
refcount, of_node_full_name(dn));
@@ -184,11 +184,11 @@ static int pnv_php_populate_changeset(struct of_changeset *ocs,
for_each_child_of_node(dn, child) {
ret = of_changeset_attach_node(ocs, child);
- if (unlikely(ret))
+ if (ret)
break;
ret = pnv_php_populate_changeset(ocs, child);
- if (unlikely(ret))
+ if (ret)
break;
}
@@ -201,7 +201,7 @@ static void *pnv_php_add_one_pdn(struct device_node *dn, void *data)
struct pci_dn *pdn;
pdn = pci_add_device_node_info(hose, dn);
- if (unlikely(!pdn))
+ if (!pdn)
return ERR_PTR(-ENOMEM);
return NULL;
@@ -224,21 +224,21 @@ static int pnv_php_add_devtree(struct pnv_php_slot *php_slot)
* fits the real size.
*/
fdt1 = kzalloc(0x10000, GFP_KERNEL);
- if (unlikely(!fdt1)) {
+ if (!fdt1) {
ret = -ENOMEM;
dev_warn(&php_slot->pdev->dev, "Cannot alloc FDT blob\n");
goto out;
}
ret = pnv_pci_get_device_tree(php_slot->dn->phandle, fdt1, 0x10000);
- if (unlikely(ret)) {
+ if (ret) {
dev_warn(&php_slot->pdev->dev, "Error %d getting FDT blob\n",
ret);
goto free_fdt1;
}
fdt = kzalloc(fdt_totalsize(fdt1), GFP_KERNEL);
- if (unlikely(!fdt)) {
+ if (!fdt) {
ret = -ENOMEM;
dev_warn(&php_slot->pdev->dev, "Cannot %d bytes memory\n",
fdt_totalsize(fdt1));
@@ -248,7 +248,7 @@ static int pnv_php_add_devtree(struct pnv_php_slot *php_slot)
/* Unflatten device tree blob */
memcpy(fdt, fdt1, fdt_totalsize(fdt1));
dt = of_fdt_unflatten_tree(fdt, php_slot->dn, NULL);
- if (unlikely(!dt)) {
+ if (!dt) {
ret = -EINVAL;
dev_warn(&php_slot->pdev->dev, "Cannot unflatten FDT\n");
goto free_fdt;
@@ -258,7 +258,7 @@ static int pnv_php_add_devtree(struct pnv_php_slot *php_slot)
of_changeset_init(&php_slot->ocs);
pnv_php_reverse_nodes(php_slot->dn);
ret = pnv_php_populate_changeset(&php_slot->ocs, php_slot->dn);
- if (unlikely(ret)) {
+ if (ret) {
pnv_php_reverse_nodes(php_slot->dn);
dev_warn(&php_slot->pdev->dev, "Error %d populating changeset\n",
ret);
@@ -267,7 +267,7 @@ static int pnv_php_add_devtree(struct pnv_php_slot *php_slot)
php_slot->dn->child = NULL;
ret = of_changeset_apply(&php_slot->ocs);
- if (unlikely(ret)) {
+ if (ret) {
dev_warn(&php_slot->pdev->dev, "Error %d applying changeset\n",
ret);
goto destroy_changeset;
@@ -301,7 +301,7 @@ int pnv_php_set_slot_power_state(struct hotplug_slot *slot,
int ret;
ret = pnv_pci_set_power_state(php_slot->id, state, &msg);
- if (likely(ret > 0)) {
+ if (ret > 0) {
if (be64_to_cpu(msg.params[1]) != php_slot->dn->phandle ||
be64_to_cpu(msg.params[2]) != state ||
be64_to_cpu(msg.params[3]) != OPAL_SUCCESS) {
@@ -311,7 +311,7 @@ int pnv_php_set_slot_power_state(struct hotplug_slot *slot,
be64_to_cpu(msg.params[3]));
return -ENOMSG;
}
- } else if (unlikely(ret < 0)) {
+ } else if (ret < 0) {
dev_warn(&php_slot->pdev->dev, "Error %d powering %s\n",
ret, (state == OPAL_PCI_SLOT_POWER_ON) ? "on" : "off");
return ret;
@@ -338,7 +338,7 @@ static int pnv_php_get_power_state(struct hotplug_slot *slot, u8 *state)
* be on.
*/
ret = pnv_pci_get_power_state(php_slot->id, &power_state);
- if (unlikely(ret)) {
+ if (ret) {
dev_warn(&php_slot->pdev->dev, "Error %d getting power status\n",
ret);
} else {
@@ -360,7 +360,7 @@ static int pnv_php_get_adapter_state(struct hotplug_slot *slot, u8 *state)
* get that, it will fail back to be empty.
*/
ret = pnv_pci_get_presence_state(php_slot->id, &presence);
- if (likely(ret >= 0)) {
+ if (ret >= 0) {
*state = presence;
slot->info->adapter_status = presence;
ret = 0;
@@ -393,7 +393,7 @@ static int pnv_php_enable(struct pnv_php_slot *php_slot, bool rescan)
/* Retrieve slot presence status */
ret = pnv_php_get_adapter_state(slot, &presence);
- if (unlikely(ret))
+ if (ret)
return ret;
/* Proceed if there have nothing behind the slot */
@@ -414,7 +414,7 @@ static int pnv_php_enable(struct pnv_php_slot *php_slot, bool rescan)
php_slot->power_state_check = true;
ret = pnv_php_get_power_state(slot, &power_status);
- if (unlikely(ret))
+ if (ret)
return ret;
if (power_status != OPAL_PCI_SLOT_POWER_ON)
@@ -423,7 +423,7 @@ static int pnv_php_enable(struct pnv_php_slot *php_slot, bool rescan)
/* Check the power status. Scan the slot if it is already on */
ret = pnv_php_get_power_state(slot, &power_status);
- if (unlikely(ret))
+ if (ret)
return ret;
if (power_status == OPAL_PCI_SLOT_POWER_ON)
@@ -431,7 +431,7 @@ static int pnv_php_enable(struct pnv_php_slot *php_slot, bool rescan)
/* Power is off, turn it on and then scan the slot */
ret = pnv_php_set_slot_power_state(slot, OPAL_PCI_SLOT_POWER_ON);
- if (unlikely(ret))
+ if (ret)
return ret;
scan:
@@ -515,27 +515,27 @@ static struct pnv_php_slot *pnv_php_alloc_slot(struct device_node *dn)
uint64_t id;
label = of_get_property(dn, "ibm,slot-label", NULL);
- if (unlikely(!label))
+ if (!label)
return NULL;
if (pnv_pci_get_slot_id(dn, &id))
return NULL;
bus = pci_find_bus_by_node(dn);
- if (unlikely(!bus))
+ if (!bus)
return NULL;
php_slot = kzalloc(sizeof(*php_slot), GFP_KERNEL);
- if (unlikely(!php_slot))
+ if (!php_slot)
return NULL;
php_slot->name = kstrdup(label, GFP_KERNEL);
- if (unlikely(!php_slot->name)) {
+ if (!php_slot->name) {
kfree(php_slot);
return NULL;
}
- if (likely(dn->child && PCI_DN(dn->child)))
+ if (dn->child && PCI_DN(dn->child))
php_slot->slot_no = PCI_SLOT(PCI_DN(dn->child)->devfn);
else
php_slot->slot_no = -1; /* Placeholder slot */
@@ -567,7 +567,7 @@ static int pnv_php_register_slot(struct pnv_php_slot *php_slot)
/* Check if the slot is registered or not */
parent = pnv_php_find_slot(php_slot->dn);
- if (unlikely(parent)) {
+ if (parent) {
pnv_php_put_slot(parent);
return -EEXIST;
}
@@ -575,7 +575,7 @@ static int pnv_php_register_slot(struct pnv_php_slot *php_slot)
/* Register PCI slot */
ret = pci_hp_register(&php_slot->slot, php_slot->bus,
php_slot->slot_no, php_slot->name);
- if (unlikely(ret)) {
+ if (ret) {
dev_warn(&php_slot->pdev->dev, "Error %d registering slot\n",
ret);
return ret;
@@ -625,15 +625,15 @@ static int pnv_php_register_one(struct device_node *dn)
return -ENXIO;
php_slot = pnv_php_alloc_slot(dn);
- if (unlikely(!php_slot))
+ if (!php_slot)
return -ENODEV;
ret = pnv_php_register_slot(php_slot);
- if (unlikely(ret))
+ if (ret)
goto free_slot;
ret = pnv_php_enable(php_slot, false);
- if (unlikely(ret))
+ if (ret)
goto unregister_slot;
return 0;
--
2.1.0
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