2022-03-25 18:27:36

by Jakob Koschel

Subject: [PATCH] w1: replace usage of found with dedicated list iterator variable

To move the list iterator variable into the list_for_each_entry_*()
macro in the future it should be avoided to use the list iterator
variable after the loop body.

To *never* use the list iterator variable after the loop it was
concluded to use a separate iterator variable instead of a
found boolean [1].

This removes the need to use a found variable and simply checking if
the variable was set, can determine if the break/goto was hit.

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/
Signed-off-by: Jakob Koschel <[email protected]>
---
drivers/w1/w1.c | 32 +++++++++++++++-----------------
1 file changed, 15 insertions(+), 17 deletions(-)

diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c
index f2ae2e563dc5..1219476cce88 100644
--- a/drivers/w1/w1.c
+++ b/drivers/w1/w1.c
@@ -830,49 +830,47 @@ int w1_slave_detach(struct w1_slave *sl)

struct w1_master *w1_search_master_id(u32 id)
{
- struct w1_master *dev;
- int found = 0;
+ struct w1_master *dev = NULL, *iter;

mutex_lock(&w1_mlock);
- list_for_each_entry(dev, &w1_masters, w1_master_entry) {
- if (dev->id == id) {
- found = 1;
- atomic_inc(&dev->refcnt);
+ list_for_each_entry(iter, &w1_masters, w1_master_entry) {
+ if (iter->id == id) {
+ dev = iter;
+ atomic_inc(&iter->refcnt);
break;
}
}
mutex_unlock(&w1_mlock);

- return (found)?dev:NULL;
+ return dev;
}

struct w1_slave *w1_search_slave(struct w1_reg_num *id)
{
struct w1_master *dev;
- struct w1_slave *sl = NULL;
- int found = 0;
+ struct w1_slave *sl = NULL, *iter;

mutex_lock(&w1_mlock);
list_for_each_entry(dev, &w1_masters, w1_master_entry) {
mutex_lock(&dev->list_mutex);
- list_for_each_entry(sl, &dev->slist, w1_slave_entry) {
- if (sl->reg_num.family == id->family &&
- sl->reg_num.id == id->id &&
- sl->reg_num.crc == id->crc) {
- found = 1;
+ list_for_each_entry(iter, &dev->slist, w1_slave_entry) {
+ if (iter->reg_num.family == id->family &&
+ iter->reg_num.id == id->id &&
+ iter->reg_num.crc == id->crc) {
+ sl = iter;
atomic_inc(&dev->refcnt);
- atomic_inc(&sl->refcnt);
+ atomic_inc(&iter->refcnt);
break;
}
}
mutex_unlock(&dev->list_mutex);

- if (found)
+ if (sl)
break;
}
mutex_unlock(&w1_mlock);

- return (found)?sl:NULL;
+ return sl;
}

void w1_reconnect_slaves(struct w1_family *f, int attach)

base-commit: f443e374ae131c168a065ea1748feac6b2e76613
--
2.25.1

2023-05-06 09:02:59

by Krzysztof Kozlowski

Subject: Re: [PATCH] w1: replace usage of found with dedicated list iterator variable

On 24/03/2022 08:32, Jakob Koschel wrote:
> To move the list iterator variable into the list_for_each_entry_*()
> macro in the future it should be avoided to use the list iterator
> variable after the loop body.
>
> To *never* use the list iterator variable after the loop it was
> concluded to use a separate iterator variable instead of a
> found boolean [1].
>
> This removes the need to use a found variable and simply checking if
> the variable was set, can determine if the break/goto was hit.
>
> Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/
> Signed-off-by: Jakob Koschel <[email protected]>
> ---
> drivers/w1/w1.c | 32 +++++++++++++++-----------------
> 1 file changed, 15 insertions(+), 17 deletions(-)

Hi,

I am going through old w1 patches and wanted to apply this, but it pops
a checkpatch warning about indentation. Can you fix the warning and send
a new version?

Best regards,
Krzysztof