[PATCH 0/2 v4 RESEND] drivers: arch_topology: introduce automatic cleanup feature
From: Vincenzo Mezzela
Date: Fri Jun 07 2024 - 12:36:31 EST
Hi,
I am resending this patch series rebased on top of -rc2 as the old one [1] might
have got lost deep in the mailbox.
This patch series introduces the automatic cleanup feature using the __free
attribute. With this modification, resources allocated with __free are
automatically released at the end of the scope.
In some cases, modifying the structure of loops is necessary to utilize the
__free attribute effectively. For example:
```
struct device_node *t;
do {
t = of_get_child_by_name(..);
if (t) {
// some code here
of_node_put(t);
}
i++;
} while (t);
// ^
// |
// device_node here
```
To use the __free attribute here, we need to move the declaration of the device_node
within the loop, otherwise the automatic cleanup is called only at the end of the
function, and not at end of each iteration of the loop, being it scope-based.
However, moving the declaration of the device_node within the loop, we can no
longer check the exit condition in the loop statement, being it outside
the loop's scope.
Therefore, this work is split into two patches. The first patch moves the exit
condition of the loop directly within the loop's scope with an explicit break
statement:
```
struct device_node *t;
do {
t = of_get_child_by_name(..);
if (!t)
break;
// some code here
of_node_put(t);
i++;
} while (1);
```
The second patch eliminates all of_node_put() calls, introducing the __free
attribute to the device_node.
changes in v2:
- check loop exit condition within the loop
- add cleanup.h header
changes in v3:
- split patch in two
- fix misalignment
- fix checkpatch warnings
- replace break with return statement where possible
changes in v4:
- fix commit subject
- fix coding style
- [1] https://lore.kernel.org/all/Zl2CjZ9mCpK1ylMf@bogus/
Vincenzo Mezzela (2):
drivers: arch_topology: Refactor do-while loops
drivers: arch_topology: use __free attribute instead of of_node_put()
drivers/base/arch_topology.c | 145 +++++++++++++++++------------------
1 file changed, 72 insertions(+), 73 deletions(-)
--
2.34.1