PM / Domains: Allocate memory outside domain locks
In preparation for supporting IRQ-safe domains, allocate domain data
outside the domain locks. These functions are not called in an atomic
context, so we can always allocate memory using GFP_KERNEL. By
allocating memory before the locks, we can safely lock the domain using
spinlocks instead of mutexes.
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index e1c0174..f932058 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -1311,13 +1311,17 @@
int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
struct generic_pm_domain *subdomain)
{
- struct gpd_link *link;
+ struct gpd_link *link, *itr;
int ret = 0;
if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
|| genpd == subdomain)
return -EINVAL;
+ link = kzalloc(sizeof(*link), GFP_KERNEL);
+ if (!link)
+ return -ENOMEM;
+
mutex_lock(&genpd->lock);
mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
@@ -1327,18 +1331,13 @@
goto out;
}
- list_for_each_entry(link, &genpd->master_links, master_node) {
- if (link->slave == subdomain && link->master == genpd) {
+ list_for_each_entry(itr, &genpd->master_links, master_node) {
+ if (itr->slave == subdomain && itr->master == genpd) {
ret = -EINVAL;
goto out;
}
}
- link = kzalloc(sizeof(*link), GFP_KERNEL);
- if (!link) {
- ret = -ENOMEM;
- goto out;
- }
link->master = genpd;
list_add_tail(&link->master_node, &genpd->master_links);
link->slave = subdomain;
@@ -1349,7 +1348,8 @@
out:
mutex_unlock(&subdomain->lock);
mutex_unlock(&genpd->lock);
-
+ if (ret)
+ kfree(link);
return ret;
}