Currently, __clk_core_init() allows failure of the kcalloc() for the
core->parents. So, clk_fetch_parent_index() and __clk_init_parent()
also try to allocate core->parents in case it has not been allocated
yet. Scattering memory allocation here and there makes things
complicated.
Like other clk_core members, allocate core->parents in clk_register()
and let it fail in case of memory shortage. If we cannot allocate
such a small piece of memory, the system is already insane. There is
no point to postpone the memory allocation.
Also, allocate core->parents regardless of core->num_parents. We want
it even if core->num_parents == 1 because clk_fetch_parent_index()
might be called against the clk_core with a single parent.
If core->num_parents == 0, core->parents is set to ZERO_SIZE_PTR. It
is harmless because no access happens to core->parents in such a case.
Signed-off-by: Masahiro Yamada <yamada.masah...@socionext.com>
---
drivers/clk/clk.c | 51 +++++++++++++++++++--------------------------------
1 file changed, 19 insertions(+), 32 deletions(-)
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 0f80c69..e05084e 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -1067,13 +1067,6 @@ static int clk_fetch_parent_index(struct clk_core *core,
{
int i;
- if (!core->parents) {
- core->parents = kcalloc(core->num_parents,
- sizeof(*core->parents), GFP_KERNEL);
- if (!core->parents)
- return -ENOMEM;
- }
-
/*
* find index of new parent clock using cached parent ptrs,
* or if not yet cached, use string name comparison and cache
@@ -1700,11 +1693,6 @@ static struct clk_core *__clk_init_parent(struct
clk_core *core)
index = core->ops->get_parent(core->hw);
- if (!core->parents)
- core->parents =
- kcalloc(core->num_parents, sizeof(*core->parents),
- GFP_KERNEL);
-
ret = clk_core_get_parent_by_index(core, index);
out:
@@ -2343,26 +2331,15 @@ static int __clk_core_init(struct clk_core *core)
__func__, core->name);
/*
- * Allocate an array of struct clk *'s to avoid unnecessary string
- * look-ups of clk's possible parents. This can fail for clocks passed
- * in to clk_init during early boot; thus any access to core->parents[]
- * must always check for a NULL pointer and try to populate it if
- * necessary.
+ * clk_core_lookup returns NULL for parents that have not been
+ * clk_init'd; thus any access to clk->parents[] must check
+ * for a NULL pointer. We can always perform lazy lookups for
+ * missing parents later on.
*/
- if (core->num_parents > 1) {
- core->parents = kcalloc(core->num_parents,
- sizeof(*core->parents), GFP_KERNEL);
- /*
- * clk_core_lookup returns NULL for parents that have not been
- * clk_init'd; thus any access to clk->parents[] must check
- * for a NULL pointer. We can always perform lazy lookups for
- * missing parents later on.
- */
- if (core->parents)
- for (i = 0; i < core->num_parents; i++)
- core->parents[i] =
- clk_core_lookup(core->parent_names[i]);
- }
+ if (core->parents)
+ for (i = 0; i < core->num_parents; i++)
+ core->parents[i] =
+ clk_core_lookup(core->parent_names[i]);
core->parent = __clk_init_parent(core);
@@ -2560,12 +2537,20 @@ struct clk *clk_register(struct device *dev, struct
clk_hw *hw)
}
}
+ /* avoid unnecessary string look-ups of clk_core's possible parents. */
+ core->parents = kcalloc(core->num_parents, sizeof(*core->parents),
+ GFP_KERNEL);
+ if (!core->parents) {
+ ret = -ENOMEM;
+ goto fail_parents;
+ };
+
INIT_HLIST_HEAD(&core->clks);
hw->clk = __clk_create_clk(hw, NULL, NULL);
if (IS_ERR(hw->clk)) {
ret = PTR_ERR(hw->clk);
- goto fail_parent_names_copy;
+ goto fail_parents;
}
ret = __clk_core_init(core);
@@ -2575,6 +2560,8 @@ struct clk *clk_register(struct device *dev, struct
clk_hw *hw)
__clk_free_clk(hw->clk);
hw->clk = NULL;
+fail_parents:
+ kfree(core->parents);
fail_parent_names_copy:
while (--i >= 0)
kfree_const(core->parent_names[i]);
--
1.9.1
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