Here's a small patch to reduce the nr. of pointer dereferences in
drivers/pci/hotplug/shpchp_core.c
Benefits:
- micro speed optimization due to fewer pointer derefs
- get rid of a pointless cast of kmalloc() return value
- generated code is slightly smaller
- better readability
Please consider applying.
Signed-off-by: Jesper Juhl <[email protected]>
---
drivers/pci/hotplug/shpchp_core.c | 92 +++++++++++++++++++++-----------------
1 files changed, 52 insertions(+), 40 deletions(-)
orig:
text data bss dec hex filename
5917 448 16 6381 18ed drivers/pci/hotplug/shpchp_core.o
patched:
text data bss dec hex filename
5896 448 16 6360 18d8 drivers/pci/hotplug/shpchp_core.o
--- linux-2.6.15-rc5-git1-orig/drivers/pci/hotplug/shpchp_core.c 2005-12-04 18:48:04.000000000 +0100
+++ linux-2.6.15-rc5-git1/drivers/pci/hotplug/shpchp_core.c 2005-12-11 05:12:04.000000000 +0100
@@ -99,7 +99,10 @@ static void release_slot(struct hotplug_
static int init_slots(struct controller *ctrl)
{
- struct slot *new_slot;
+ struct slot *slot;
+ struct hpc_ops *hpc_ops;
+ struct hotplug_slot *hotplug_slot;
+ struct hotplug_slot_info *hotplug_slot_info;
u8 number_of_slots;
u8 slot_device;
u32 slot_number, sun;
@@ -110,58 +113,68 @@ static int init_slots(struct controller
slot_number = ctrl->first_slot;
while (number_of_slots) {
- new_slot = (struct slot *) kmalloc(sizeof(struct slot), GFP_KERNEL);
- if (!new_slot)
+ slot = kmalloc(sizeof(struct slot), GFP_KERNEL);
+ if (!slot)
goto error;
- memset(new_slot, 0, sizeof(struct slot));
- new_slot->hotplug_slot = kmalloc (sizeof (struct hotplug_slot), GFP_KERNEL);
- if (!new_slot->hotplug_slot)
+ memset(slot, 0, sizeof(struct slot));
+ slot->hotplug_slot =
+ kmalloc(sizeof(struct hotplug_slot), GFP_KERNEL);
+ if (!slot->hotplug_slot)
goto error_slot;
- memset(new_slot->hotplug_slot, 0, sizeof (struct hotplug_slot));
+ hotplug_slot = slot->hotplug_slot;
+ memset(hotplug_slot, 0, sizeof(struct hotplug_slot));
- new_slot->hotplug_slot->info = kmalloc (sizeof (struct hotplug_slot_info), GFP_KERNEL);
- if (!new_slot->hotplug_slot->info)
+ hotplug_slot->info =
+ kmalloc(sizeof(struct hotplug_slot_info), GFP_KERNEL);
+ if (!hotplug_slot->info)
goto error_hpslot;
- memset(new_slot->hotplug_slot->info, 0, sizeof (struct hotplug_slot_info));
- new_slot->hotplug_slot->name = kmalloc (SLOT_NAME_SIZE, GFP_KERNEL);
- if (!new_slot->hotplug_slot->name)
+ hotplug_slot_info = hotplug_slot->info;
+ memset(hotplug_slot_info, 0, sizeof(struct hotplug_slot_info));
+ hotplug_slot->name = kmalloc(SLOT_NAME_SIZE, GFP_KERNEL);
+ if (!hotplug_slot->name)
goto error_info;
- new_slot->magic = SLOT_MAGIC;
- new_slot->ctrl = ctrl;
- new_slot->bus = ctrl->slot_bus;
- new_slot->device = slot_device;
- new_slot->hpc_ops = ctrl->hpc_ops;
+ slot->magic = SLOT_MAGIC;
+ slot->ctrl = ctrl;
+ slot->bus = ctrl->slot_bus;
+ slot->device = slot_device;
+ slot->hpc_ops = hpc_ops = ctrl->hpc_ops;
if (shpchprm_get_physical_slot_number(ctrl, &sun,
- new_slot->bus, new_slot->device))
+ slot->bus, slot->device))
goto error_name;
- new_slot->number = sun;
- new_slot->hp_slot = slot_device - ctrl->slot_device_offset;
+ slot->number = sun;
+ slot->hp_slot = slot_device - ctrl->slot_device_offset;
/* register this slot with the hotplug pci core */
- new_slot->hotplug_slot->private = new_slot;
- new_slot->hotplug_slot->release = &release_slot;
- make_slot_name(new_slot->hotplug_slot->name, SLOT_NAME_SIZE, new_slot);
- new_slot->hotplug_slot->ops = &shpchp_hotplug_slot_ops;
-
- new_slot->hpc_ops->get_power_status(new_slot, &(new_slot->hotplug_slot->info->power_status));
- new_slot->hpc_ops->get_attention_status(new_slot, &(new_slot->hotplug_slot->info->attention_status));
- new_slot->hpc_ops->get_latch_status(new_slot, &(new_slot->hotplug_slot->info->latch_status));
- new_slot->hpc_ops->get_adapter_status(new_slot, &(new_slot->hotplug_slot->info->adapter_status));
-
- dbg("Registering bus=%x dev=%x hp_slot=%x sun=%x slot_device_offset=%x\n", new_slot->bus,
- new_slot->device, new_slot->hp_slot, new_slot->number, ctrl->slot_device_offset);
- result = pci_hp_register (new_slot->hotplug_slot);
+ hotplug_slot->private = slot;
+ hotplug_slot->release = &release_slot;
+ make_slot_name(hotplug_slot->name, SLOT_NAME_SIZE, slot);
+ hotplug_slot->ops = &shpchp_hotplug_slot_ops;
+
+ hpc_ops->get_power_status(slot,
+ &(hotplug_slot_info->power_status));
+ hpc_ops->get_attention_status(slot,
+ &(hotplug_slot_info->attention_status));
+ hpc_ops->get_latch_status(slot,
+ &(hotplug_slot_info->latch_status));
+ hpc_ops->get_adapter_status(slot,
+ &(hotplug_slot_info->adapter_status));
+
+ dbg("Registering bus=%x dev=%x hp_slot=%x sun=%x "
+ "slot_device_offset=%x\n",
+ slot->bus, slot->device, slot->hp_slot, slot->number,
+ ctrl->slot_device_offset);
+ result = pci_hp_register(hotplug_slot);
if (result) {
err ("pci_hp_register failed with error %d\n", result);
goto error_name;
}
- new_slot->next = ctrl->slot;
- ctrl->slot = new_slot;
+ slot->next = ctrl->slot;
+ ctrl->slot = slot;
number_of_slots--;
slot_device++;
@@ -169,15 +182,14 @@ static int init_slots(struct controller
}
return 0;
-
error_name:
- kfree(new_slot->hotplug_slot->name);
+ kfree(hotplug_slot->name);
error_info:
- kfree(new_slot->hotplug_slot->info);
+ kfree(hotplug_slot_info);
error_hpslot:
- kfree(new_slot->hotplug_slot);
+ kfree(hotplug_slot);
error_slot:
- kfree(new_slot);
+ kfree(slot);
error:
return result;
}
-
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