From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Heikki Krogerus <heikki.krogerus@linux.intel.com>,
Bartosz Golaszewski <bgolaszewski@baylibre.com>,
Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
linux-kernel@vger.kernel.org
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Subject: [PATCH v4 1/4] devres: Make locking straight forward in release_nodes()
Date: Mon, 17 May 2021 15:29:43 +0300 [thread overview]
Message-ID: <20210517122946.53161-1-andriy.shevchenko@linux.intel.com> (raw)
It seems for the sake of saving stack memory of couple of pointers,
the locking in release_nodes() callers becomes interesting.
Replace this logic with a straight forward locking and unlocking scheme.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
v4: rebased on top of v5.13-rc2
drivers/base/devres.c | 30 +++++++++++++++---------------
1 file changed, 15 insertions(+), 15 deletions(-)
diff --git a/drivers/base/devres.c b/drivers/base/devres.c
index 8746f2212781..7970217191e0 100644
--- a/drivers/base/devres.c
+++ b/drivers/base/devres.c
@@ -503,28 +503,18 @@ static int remove_nodes(struct device *dev,
return cnt;
}
-static int release_nodes(struct device *dev, struct list_head *first,
- struct list_head *end, unsigned long flags)
- __releases(&dev->devres_lock)
+static void release_nodes(struct device *dev, struct list_head *todo)
{
- LIST_HEAD(todo);
- int cnt;
struct devres *dr, *tmp;
- cnt = remove_nodes(dev, first, end, &todo);
-
- spin_unlock_irqrestore(&dev->devres_lock, flags);
-
/* Release. Note that both devres and devres_group are
* handled as devres in the following loop. This is safe.
*/
- list_for_each_entry_safe_reverse(dr, tmp, &todo, node.entry) {
+ list_for_each_entry_safe_reverse(dr, tmp, todo, node.entry) {
devres_log(dev, &dr->node, "REL");
dr->node.release(dev, dr->data);
kfree(dr);
}
-
- return cnt;
}
/**
@@ -537,13 +527,19 @@ static int release_nodes(struct device *dev, struct list_head *first,
int devres_release_all(struct device *dev)
{
unsigned long flags;
+ LIST_HEAD(todo);
+ int cnt;
/* Looks like an uninitialized device structure */
if (WARN_ON(dev->devres_head.next == NULL))
return -ENODEV;
+
spin_lock_irqsave(&dev->devres_lock, flags);
- return release_nodes(dev, dev->devres_head.next, &dev->devres_head,
- flags);
+ cnt = remove_nodes(dev, dev->devres_head.next, &dev->devres_head, &todo);
+ spin_unlock_irqrestore(&dev->devres_lock, flags);
+
+ release_nodes(dev, &todo);
+ return cnt;
}
/**
@@ -679,6 +675,7 @@ int devres_release_group(struct device *dev, void *id)
{
struct devres_group *grp;
unsigned long flags;
+ LIST_HEAD(todo);
int cnt = 0;
spin_lock_irqsave(&dev->devres_lock, flags);
@@ -691,7 +688,10 @@ int devres_release_group(struct device *dev, void *id)
if (!list_empty(&grp->node[1].entry))
end = grp->node[1].entry.next;
- cnt = release_nodes(dev, first, end, flags);
+ cnt = remove_nodes(dev, first, end, &todo);
+ spin_unlock_irqrestore(&dev->devres_lock, flags);
+
+ release_nodes(dev, &todo);
} else {
WARN_ON(1);
spin_unlock_irqrestore(&dev->devres_lock, flags);
--
2.30.2
next reply other threads:[~2021-05-17 12:29 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-17 12:29 Andy Shevchenko [this message]
2021-05-17 12:29 ` [PATCH v4 2/4] devres: Use list_for_each_safe_from() in remove_nodes() Andy Shevchenko
2021-05-17 12:29 ` [PATCH v4 3/4] devres: No need to call remove_nodes() when there none present Andy Shevchenko
2021-05-17 12:29 ` [PATCH v4 4/4] devres: Enable trace events Andy Shevchenko
2021-05-26 11:53 ` [PATCH v4 1/4] devres: Make locking straight forward in release_nodes() Andy Shevchenko
2021-06-11 10:12 ` Andy Shevchenko
2021-06-15 15:14 ` Greg Kroah-Hartman
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