[PATCH v3] w1: Replace usage of found with dedicated list iterator variable

From: Jakob Koschel
Date: Fri May 12 2023 - 07:36:23 EST


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@xxxxxxxxxxxxxx/ [1]
Signed-off-by: Jakob Koschel <jkl820.git@xxxxxxxxx>
---
Changes in v2:
- fix checkpatch intentation issues

Changes in v3:
- actually fix checkpatch intentation issues

Note: I've changed my email address to contributions to
jkl820.git@xxxxxxxxx, I hope that's not an issue since the v1 was still
on my old email.
---
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 9d199fed9628..a5e18de7a25a 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: cc3c44c9fda264c6d401be04e95449a57c1231c6
change-id: 20230509-w1-replace-usage-of-found-with-tmp-list-iterator-variable-c56393ff0339

Best regards,
--
Jakob Koschel <jkl820.git@xxxxxxxxx>