[PATCH 07/11] PCI: Don't allocate small resource in big empty space.

Yinghai Lu
2012-05-23T06:35:06Z

Use updated find_resource to return matched resource instead using head
of bigger range.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
drivers/pci/bus.c | 22 ++++++++++++++++++----
drivers/pci/setup-bus.c | 12 ++++++++----
drivers/pci/setup-res.c | 28 ++++++++++++++++++----------
include/linux/ioport.h | 8 ++++++++
include/linux/pci.h | 10 ++++++++++
kernel/resource.c | 22 +++++++++++++++++++---
6 files changed, 81 insertions(+), 21 deletions(-)

diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 2429f1f..a7ba102 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -110,14 +110,14 @@ void pci_bus_remove_resources(struct pci_bus *bus)
* for a specific device resource.
*/
int
-pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
+pci_bus_alloc_resource_fit(struct pci_bus *bus, struct resource *res,
resource_size_t size, resource_size_t align,
resource_size_t min, unsigned int type_mask,
resource_size_t (*alignf)(void *,
const struct resource *,
resource_size_t,
resource_size_t),
- void *alignf_data)
+ void *alignf_data, bool fit)
{
int i, ret = -ENOMEM;
struct resource *r;
@@ -148,10 +148,10 @@ again:
continue;

/* Ok, try it out.. */
- ret = allocate_resource(r, res, size,
+ ret = allocate_resource_fit(r, res, size,
max(bottom, r->start ? : min),
max, align,
- alignf, alignf_data);
+ alignf, alignf_data, fit);
if (ret == 0)
return 0;
}
@@ -164,6 +164,20 @@ again:
return ret;
}

+int
+pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
+ resource_size_t size, resource_size_t align,
+ resource_size_t min, unsigned int type_mask,
+ resource_size_t (*alignf)(void *,
+ const struct resource *,
+ resource_size_t,
+ resource_size_t),
+ void *alignf_data)
+{
+ return pci_bus_alloc_resource_fit(bus, res, size, align, min, type_mask,
+ alignf, alignf_data, false);
+}
+
/**
* pci_bus_add_device - add a single device
* @dev: device to add
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 0568f29..4d6823f 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -275,7 +275,7 @@ out:
* requests that could not satisfied to the failed_list.
*/
static void assign_requested_resources_sorted(struct list_head *head,
- struct list_head *fail_head)
+ struct list_head *fail_head, bool fit)
{
struct resource *res;
struct pci_dev_resource *dev_res;
@@ -285,7 +285,7 @@ static void assign_requested_resources_sorted(struct list_head *head,
res = dev_res->res;
idx = res - &dev_res->dev->resource[0];
if (resource_size(res) &&
- pci_assign_resource(dev_res->dev, idx)) {
+ pci_assign_resource_fit(dev_res->dev, idx, fit)) {
if (fail_head) {
/*
* if the failed res is for ROM BAR, and it will
@@ -320,6 +320,7 @@ static void __assign_resources_sorted(struct list_head *head,
LIST_HEAD(local_fail_head);
struct pci_dev_resource *save_res;
struct pci_dev_resource *dev_res;
+ bool fit = true;

/* Check if optional add_size is there */
if (!realloc_head || list_empty(realloc_head))
@@ -339,7 +340,7 @@ static void __assign_resources_sorted(struct list_head *head,
dev_res->res);

/* Try updated head list with add_size added */
- assign_requested_resources_sorted(head, &local_fail_head);
+ assign_requested_resources_sorted(head, &local_fail_head, fit);

/* all assigned with add_size ? */
if (list_empty(&local_fail_head)) {
@@ -366,9 +367,12 @@ static void __assign_resources_sorted(struct list_head *head,
}
free_list(&save_head);

+ /* will need to expand later, so not use fit */
+ fit = false;
+
requested_and_reassign:
/* Satisfy the must-have resource requests */
- assign_requested_resources_sorted(head, fail_head);
+ assign_requested_resources_sorted(head, fail_head, fit);

/* Try to satisfy any additional optional resource
requests */
diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c
index eea85da..7010ad9 100644
--- a/drivers/pci/setup-res.c
+++ b/drivers/pci/setup-res.c
@@ -128,7 +128,8 @@ void pci_disable_bridge_window(struct pci_dev *dev)
}

static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
- int resno, resource_size_t size, resource_size_t align)
+ int resno, resource_size_t size, resource_size_t align,
+ bool fit)
{
struct resource *res = dev->resource + resno;
resource_size_t min;
@@ -137,9 +138,9 @@ static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;

/* First, try exact prefetching match.. */
- ret = pci_bus_alloc_resource(bus, res, size, align, min,
+ ret = pci_bus_alloc_resource_fit(bus, res, size, align, min,
IORESOURCE_PREFETCH,
- pcibios_align_resource, dev);
+ pcibios_align_resource, dev, fit);

if (ret < 0 && (res->flags & IORESOURCE_PREFETCH)) {
/*
@@ -148,8 +149,8 @@ static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
* But a prefetching area can handle a non-prefetching
* window (it will just not perform as well).
*/
- ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
- pcibios_align_resource, dev);
+ ret = pci_bus_alloc_resource_fit(bus, res, size, align, min, 0,
+ pcibios_align_resource, dev, fit);
}
return ret;
}
@@ -206,7 +207,8 @@ static int pci_revert_fw_address(struct resource *res, struct pci_dev *dev,
return ret;
}

-static int _pci_assign_resource(struct pci_dev *dev, int resno, int size, resource_size_t min_align)
+static int _pci_assign_resource(struct pci_dev *dev, int resno, int size,
+ resource_size_t min_align, bool fit)
{
struct resource *res = dev->resource + resno;
struct pci_bus *bus;
@@ -214,7 +216,8 @@ static int _pci_assign_resource(struct pci_dev *dev, int resno, int size, resour
char *type;

bus = dev->bus;
- while ((ret = __pci_assign_resource(bus, dev, resno, size, min_align))) {
+ while ((ret = __pci_assign_resource(bus, dev, resno, size,
+ min_align, fit))) {
if (!bus->parent || !bus->self->transparent)
break;
bus = bus->parent;
@@ -253,7 +256,7 @@ int pci_reassign_resource(struct pci_dev *dev, int resno, resource_size_t addsiz

/* already aligned with min_align */
new_size = resource_size(res) + addsize;
- ret = _pci_assign_resource(dev, resno, new_size, min_align);
+ ret = _pci_assign_resource(dev, resno, new_size, min_align, false);
if (!ret) {
res->flags &= ~IORESOURCE_STARTALIGN;
dev_info(&dev->dev, "BAR %d: reassigned %pR\n", resno, res);
@@ -263,7 +266,7 @@ int pci_reassign_resource(struct pci_dev *dev, int resno, resource_size_t addsiz
return ret;
}

-int pci_assign_resource(struct pci_dev *dev, int resno)
+int pci_assign_resource_fit(struct pci_dev *dev, int resno, bool fit)
{
struct resource *res = dev->resource + resno;
resource_size_t align, size;
@@ -279,7 +282,7 @@ int pci_assign_resource(struct pci_dev *dev, int resno)

bus = dev->bus;
size = resource_size(res);
- ret = _pci_assign_resource(dev, resno, size, align);
+ ret = _pci_assign_resource(dev, resno, size, align, fit);

/*
* If we failed to assign anything, let's try the address
@@ -298,6 +301,11 @@ int pci_assign_resource(struct pci_dev *dev, int resno)
return ret;
}

+int pci_assign_resource(struct pci_dev *dev, int resno)
+{
+ return pci_assign_resource_fit(dev, resno, false);
+}
+
int pci_enable_resources(struct pci_dev *dev, int mask)
{
u16 cmd, old_cmd;
diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index 589e0e7..255852e 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -148,6 +148,14 @@ extern struct resource *insert_resource_conflict(struct resource *parent, struct
extern int insert_resource(struct resource *parent, struct resource *new);
extern void insert_resource_expand_to_fit(struct resource *root, struct resource *new);
extern void arch_remove_reservations(struct resource *avail);
+int allocate_resource_fit(struct resource *root, struct resource *new,
+ resource_size_t size, resource_size_t min,
+ resource_size_t max, resource_size_t align,
+ resource_size_t (*alignf)(void *,
+ const struct resource *,
+ resource_size_t,
+ resource_size_t),
+ void *alignf_data, bool fit);
extern int allocate_resource(struct resource *root, struct resource *new,
resource_size_t size, resource_size_t min,
resource_size_t max, resource_size_t align,
diff --git a/include/linux/pci.h b/include/linux/pci.h
index a0e2d7f..c0704a0 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -827,6 +827,7 @@ int __pci_reset_function_locked(struct pci_dev *dev);
int pci_reset_function(struct pci_dev *dev);
void pci_update_resource(struct pci_dev *dev, int resno);
int __must_check pci_assign_resource(struct pci_dev *dev, int i);
+int __must_check pci_assign_resource_fit(struct pci_dev *dev, int i, bool fit);
int __must_check pci_reassign_resource(struct pci_dev *dev, int i, resource_size_t add_size, resource_size_t align);
int pci_select_bars(struct pci_dev *dev, unsigned long flags);

@@ -943,6 +944,15 @@ int __must_check pci_bus_alloc_resource(struct pci_bus *bus,
resource_size_t,
resource_size_t),
void *alignf_data);
+int __must_check pci_bus_alloc_resource_fit(struct pci_bus *bus,
+ struct resource *res, resource_size_t size,
+ resource_size_t align, resource_size_t min,
+ unsigned int type_mask,
+ resource_size_t (*alignf)(void *,
+ const struct resource *,
+ resource_size_t,
+ resource_size_t),
+ void *alignf_data, bool fit);
void pci_enable_bridges(struct pci_bus *bus);

/* Proper probing supporting hot-pluggable devices */
diff --git a/kernel/resource.c b/kernel/resource.c
index 45ab24d..b4dae55 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -580,7 +580,7 @@ static int __allocate_resource(struct resource *root, struct resource *new,
const struct resource *,
resource_size_t,
resource_size_t),
- void *alignf_data, bool lock)
+ void *alignf_data, bool lock, bool fit)
{
int err;
struct resource_constraint constraint;
@@ -602,13 +602,28 @@ static int __allocate_resource(struct resource *root, struct resource *new,

if (lock)
write_lock(&resource_lock);
- err = find_resource(root, new, size, &constraint, false);
+ err = find_resource(root, new, size, &constraint, fit);
if (err >= 0 && __request_resource(root, new))
err = -EBUSY;
if (lock)
write_unlock(&resource_lock);
return err;
}
+int allocate_resource_fit(struct resource *root, struct resource *new,
+ resource_size_t size, resource_size_t min,
+ resource_size_t max, resource_size_t align,
+ resource_size_t (*alignf)(void *,
+ const struct resource *,
+ resource_size_t,
+ resource_size_t),
+ void *alignf_data, bool fit)
+{
+ bool lock = true;
+
+ return __allocate_resource(root, new, size, min, max, align,
+ alignf, alignf_data, lock, fit);
+}
+
int allocate_resource(struct resource *root, struct resource *new,
resource_size_t size, resource_size_t min,
resource_size_t max, resource_size_t align,
@@ -619,9 +634,10 @@ int allocate_resource(struct resource *root, struct resource *new,
void *alignf_data)
{
bool lock = true;
+ bool fit = false;

return __allocate_resource(root, new, size, min, max, align,
- alignf, alignf_data, lock);
+ alignf, alignf_data, lock, fit);
}

EXPORT_SYMBOL(allocate_resource);
--
1.7.7