[RFC PATCH v3] clk: Use new helper in managed functions
From: Marc Gonzalez
Date: Fri Jan 24 2020 - 11:17:22 EST
Introduce devm_add() to factorize devres_alloc/devres_add calls.
Using that helper produces simpler code, and smaller object size.
E.g. with gcc-arm-9.2-2019.12-x86_64-aarch64-none-linux-gnu:
text data bss dec hex filename
- 1708 80 0 1788 6fc drivers/clk/clk-devres.o
+ 1524 80 0 1604 644 drivers/clk/clk-devres.o
Signed-off-by: Marc Gonzalez <marc.w.gonzalez@xxxxxxx>
---
Differences from v2 to v3
x Make devm_add() return an error-code rather than the raw data pointer
(in case devres_alloc ever returns an ERR_PTR) as suggested by Geert
x Provide a variadic version devm_vadd() to work with structs as suggested
by Geert
x Don't use nested ifs in clk_devm* implementations (hopefully simpler
code logic to follow) as suggested by Geert
Questions:
x This patch might need to be split in two? (Introduce the new API, then use it)
x Convert other subsystems to show the value of this proposal?
x Maybe comment the API usage somewhere
---
drivers/base/devres.c | 15 ++++++
drivers/clk/clk-devres.c | 99 ++++++++++++++--------------------------
include/linux/device.h | 3 ++
3 files changed, 53 insertions(+), 64 deletions(-)
diff --git a/drivers/base/devres.c b/drivers/base/devres.c
index 0bbb328bd17f..b2603789755b 100644
--- a/drivers/base/devres.c
+++ b/drivers/base/devres.c
@@ -685,6 +685,21 @@ int devres_release_group(struct device *dev, void *id)
}
EXPORT_SYMBOL_GPL(devres_release_group);
+int devm_add(struct device *dev, dr_release_t func, void *arg, size_t size)
+{
+ void *data = devres_alloc(func, size, GFP_KERNEL);
+
+ if (!data) {
+ func(dev, arg);
+ return -ENOMEM;
+ }
+
+ memcpy(data, arg, size);
+ devres_add(dev, data);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(devm_add);
+
/*
* Custom devres actions allow inserting a simple function call
* into the teadown sequence.
diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c
index be160764911b..1da69d273855 100644
--- a/drivers/clk/clk-devres.c
+++ b/drivers/clk/clk-devres.c
@@ -4,26 +4,22 @@
#include <linux/export.h>
#include <linux/gfp.h>
-static void devm_clk_release(struct device *dev, void *res)
+static void my_clk_put(struct device *dev, void *res)
{
clk_put(*(struct clk **)res);
}
struct clk *devm_clk_get(struct device *dev, const char *id)
{
- struct clk **ptr, *clk;
-
- ptr = devres_alloc(devm_clk_release, sizeof(*ptr), GFP_KERNEL);
- if (!ptr)
- return ERR_PTR(-ENOMEM);
-
- clk = clk_get(dev, id);
- if (!IS_ERR(clk)) {
- *ptr = clk;
- devres_add(dev, ptr);
- } else {
- devres_free(ptr);
- }
+ int ret;
+ struct clk *clk = clk_get(dev, id);
+
+ if (IS_ERR(clk))
+ return clk;
+
+ ret = devm_add(dev, my_clk_put, &clk, sizeof(clk));
+ if (ret)
+ return ERR_PTR(ret);
return clk;
}
@@ -40,14 +36,14 @@ struct clk *devm_clk_get_optional(struct device *dev, const char *id)
}
EXPORT_SYMBOL(devm_clk_get_optional);
-struct clk_bulk_devres {
- struct clk_bulk_data *clks;
+struct clk_bulk_args {
int num_clks;
+ struct clk_bulk_data *clks;
};
-static void devm_clk_bulk_release(struct device *dev, void *res)
+static void my_clk_bulk_put(struct device *dev, void *res)
{
- struct clk_bulk_devres *devres = res;
+ struct clk_bulk_args *devres = res;
clk_bulk_put(devres->num_clks, devres->clks);
}
@@ -55,25 +51,17 @@ static void devm_clk_bulk_release(struct device *dev, void *res)
static int __devm_clk_bulk_get(struct device *dev, int num_clks,
struct clk_bulk_data *clks, bool optional)
{
- struct clk_bulk_devres *devres;
int ret;
- devres = devres_alloc(devm_clk_bulk_release,
- sizeof(*devres), GFP_KERNEL);
- if (!devres)
- return -ENOMEM;
-
if (optional)
ret = clk_bulk_get_optional(dev, num_clks, clks);
else
ret = clk_bulk_get(dev, num_clks, clks);
- if (!ret) {
- devres->clks = clks;
- devres->num_clks = num_clks;
- devres_add(dev, devres);
- } else {
- devres_free(devres);
- }
+
+ if (ret)
+ return ret;
+
+ ret = devm_vadd(dev, my_clk_bulk_put, clk_bulk_args, num_clks, clks);
return ret;
}
@@ -95,24 +83,15 @@ EXPORT_SYMBOL_GPL(devm_clk_bulk_get_optional);
int __must_check devm_clk_bulk_get_all(struct device *dev,
struct clk_bulk_data **clks)
{
- struct clk_bulk_devres *devres;
int ret;
+ int num_clks = clk_bulk_get_all(dev, clks);
- devres = devres_alloc(devm_clk_bulk_release,
- sizeof(*devres), GFP_KERNEL);
- if (!devres)
- return -ENOMEM;
-
- ret = clk_bulk_get_all(dev, &devres->clks);
- if (ret > 0) {
- *clks = devres->clks;
- devres->num_clks = ret;
- devres_add(dev, devres);
- } else {
- devres_free(devres);
- }
+ if (num_clks <= 0)
+ return num_clks;
- return ret;
+ ret = devm_vadd(dev, my_clk_bulk_put, clk_bulk_args, num_clks, *clks);
+
+ return ret ? : num_clks;
}
EXPORT_SYMBOL_GPL(devm_clk_bulk_get_all);
@@ -128,30 +107,22 @@ static int devm_clk_match(struct device *dev, void *res, void *data)
void devm_clk_put(struct device *dev, struct clk *clk)
{
- int ret;
-
- ret = devres_release(dev, devm_clk_release, devm_clk_match, clk);
-
- WARN_ON(ret);
+ WARN_ON(devres_release(dev, my_clk_put, devm_clk_match, clk));
}
EXPORT_SYMBOL(devm_clk_put);
struct clk *devm_get_clk_from_child(struct device *dev,
struct device_node *np, const char *con_id)
{
- struct clk **ptr, *clk;
-
- ptr = devres_alloc(devm_clk_release, sizeof(*ptr), GFP_KERNEL);
- if (!ptr)
- return ERR_PTR(-ENOMEM);
-
- clk = of_clk_get_by_name(np, con_id);
- if (!IS_ERR(clk)) {
- *ptr = clk;
- devres_add(dev, ptr);
- } else {
- devres_free(ptr);
- }
+ int ret;
+ struct clk *clk = of_clk_get_by_name(np, con_id);
+
+ if (IS_ERR(clk))
+ return clk;
+
+ ret = devm_add(dev, my_clk_put, &clk, sizeof(clk));
+ if (ret)
+ return ERR_PTR(ret);
return clk;
}
diff --git a/include/linux/device.h b/include/linux/device.h
index e226030c1df3..9f18582fc0f9 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -969,6 +969,9 @@ void __iomem *devm_of_iomap(struct device *dev,
struct device_node *node, int index,
resource_size_t *size);
+int devm_add(struct device *dev, dr_release_t func, void *arg, size_t size);
+#define devm_vadd(dev, func, type, args...) \
+ devm_add(dev, func, &(struct type){args}, sizeof(struct type))
/* allows to add/remove a custom action to devres stack */
int devm_add_action(struct device *dev, void (*action)(void *), void *data);
void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
--
2.17.1