[PATCH 02/10] hwspinlock/core: simplify 'owner' handling

From: Ohad Ben-Cohen
Date: Mon Sep 12 2011 - 12:47:49 EST


Use struct device_driver's owner member instead of asking drivers to
explicitly pass the owner again.

This simplifies drivers and also save some memory, since there's no
point now in maintaining a separate owner pointer per hwspinlock.

Signed-off-by: Ohad Ben-Cohen <ohad@xxxxxxxxxx>
---
Documentation/hwspinlock.txt | 6 ++----
drivers/hwspinlock/hwspinlock_core.c | 4 ++--
drivers/hwspinlock/hwspinlock_internal.h | 4 +---
drivers/hwspinlock/omap_hwspinlock.c | 2 +-
4 files changed, 6 insertions(+), 10 deletions(-)

diff --git a/Documentation/hwspinlock.txt b/Documentation/hwspinlock.txt
index 7dcd1a4..bbaa464 100644
--- a/Documentation/hwspinlock.txt
+++ b/Documentation/hwspinlock.txt
@@ -256,18 +256,16 @@ underlying hwspinlock implementation using the hwspin_lock_register() API.
* @ops: vendor-specific hwspinlock handlers
* @id: a global, unique, system-wide, index of the lock.
* @lock: initialized and used by hwspinlock core
- * @owner: underlying implementation module, used to maintain module ref count
*/
struct hwspinlock {
struct device *dev;
const struct hwspinlock_ops *ops;
int id;
spinlock_t lock;
- struct module *owner;
};

-The underlying implementation is responsible to assign the dev, ops, id and
-owner members. The lock member, OTOH, is initialized and used by the hwspinlock
+The underlying implementation is responsible to assign the dev, ops and id
+members. The lock member, OTOH, is initialized and used by the hwspinlock
core.

6. Implementation callbacks
diff --git a/drivers/hwspinlock/hwspinlock_core.c b/drivers/hwspinlock/hwspinlock_core.c
index 43a6271..af5175c 100644
--- a/drivers/hwspinlock/hwspinlock_core.c
+++ b/drivers/hwspinlock/hwspinlock_core.c
@@ -352,7 +352,7 @@ static int __hwspin_lock_request(struct hwspinlock *hwlock)
int ret;

/* prevent underlying implementation from being removed */
- if (!try_module_get(hwlock->owner)) {
+ if (!try_module_get(hwlock->dev->driver->owner)) {
dev_err(hwlock->dev, "%s: can't get owner\n", __func__);
return -EINVAL;
}
@@ -535,7 +535,7 @@ int hwspin_lock_free(struct hwspinlock *hwlock)
/* sanity check (this shouldn't happen) */
WARN_ON(tmp != hwlock);

- module_put(hwlock->owner);
+ module_put(hwlock->dev->driver->owner);

out:
spin_unlock(&hwspinlock_tree_lock);
diff --git a/drivers/hwspinlock/hwspinlock_internal.h b/drivers/hwspinlock/hwspinlock_internal.h
index 69935e6..fb25830 100644
--- a/drivers/hwspinlock/hwspinlock_internal.h
+++ b/drivers/hwspinlock/hwspinlock_internal.h
@@ -44,10 +44,9 @@ struct hwspinlock_ops {
* @ops: platform-specific hwspinlock handlers
* @id: a global, unique, system-wide, index of the lock.
* @lock: initialized and used by hwspinlock core
- * @owner: underlying implementation module, used to maintain module ref count
*
* Note: currently simplicity was opted for, but later we can squeeze some
- * memory bytes by grouping the dev, ops and owner members in a single
+ * memory bytes by grouping dev, ops in a single
* per-platform struct, and have all hwspinlocks point at it.
*/
struct hwspinlock {
@@ -55,7 +54,6 @@ struct hwspinlock {
const struct hwspinlock_ops *ops;
int id;
spinlock_t lock;
- struct module *owner;
};

#endif /* __HWSPINLOCK_HWSPINLOCK_H */
diff --git a/drivers/hwspinlock/omap_hwspinlock.c b/drivers/hwspinlock/omap_hwspinlock.c
index a8f0273..1d19fe9 100644
--- a/drivers/hwspinlock/omap_hwspinlock.c
+++ b/drivers/hwspinlock/omap_hwspinlock.c
@@ -143,7 +143,6 @@ static int __devinit omap_hwspinlock_probe(struct platform_device *pdev)
}

omap_lock->lock.dev = &pdev->dev;
- omap_lock->lock.owner = THIS_MODULE;
omap_lock->lock.id = i;
omap_lock->lock.ops = &omap_hwspinlock_ops;
omap_lock->addr = io_base + LOCK_BASE_OFFSET + sizeof(u32) * i;
@@ -208,6 +207,7 @@ static struct platform_driver omap_hwspinlock_driver = {
.remove = omap_hwspinlock_remove,
.driver = {
.name = "omap_hwspinlock",
+ .owner = THIS_MODULE,
},
};

--
1.7.4.1

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