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[PATCH v2] w1: Replace usage of found with dedicated list iterator variable

Jakob Koschel posted 1 patch 2 years, 9 months ago
There is a newer version of this series
drivers/w1/w1.c | 32 +++++++++++++++-----------------
1 file changed, 15 insertions(+), 17 deletions(-)
[PATCH v2] w1: Replace usage of found with dedicated list iterator variable
Posted by Jakob Koschel 2 years, 9 months ago 
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/ [1]
Signed-off-by: Jakob Koschel <jkl820.git@gmail.com>
---
Changes in v2:
  - fix checkpatch intentation issues

Note: I've changed my email address to contributions to
jkl820.git@gmail.com, 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..c453160684e1 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: eeac8ede17557680855031c6f305ece2378af326
change-id: 20230509-w1-replace-usage-of-found-with-tmp-list-iterator-variable-c56393ff0339

Best regards,
-- 
Jakob Koschel <jkl820.git@gmail.com>
Re: [PATCH v2] w1: Replace usage of found with dedicated list iterator variable
Posted by Krzysztof Kozlowski 2 years, 9 months ago 
On 10/05/2023 00:49, 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/ [1]
> Signed-off-by: Jakob Koschel <jkl820.git@gmail.com>
> ---
> Changes in v2:
>   - fix checkpatch intentation issues

I don't see the differences and checkpatch still complains. Are you sure
you sent v2?

Best regards,
Krzysztof
Re: [PATCH v2] w1: Replace usage of found with dedicated list iterator variable
Posted by Jakob Koschel 2 years, 9 months ago 
How strange, I just checked and my checkpatch doesn't complain.

I also redownloaded and double checked 
(b4 am 20230509-w1-replace-usage-of-found-with-tmp-list-iterator-variable-v2-1-259bf1ba44ed@gmail.com).

What's the exact issue you are seeing?

- jakob

On 23/05/12 09:27AM, Krzysztof Kozlowski wrote:
> On 10/05/2023 00:49, 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/ [1]
> > Signed-off-by: Jakob Koschel <jkl820.git@gmail.com>
> > ---
> > Changes in v2:
> >   - fix checkpatch intentation issues
> 
> I don't see the differences and checkpatch still complains. Are you sure
> you sent v2?
> 
> Best regards,
> Krzysztof
>
Re: [PATCH v2] w1: Replace usage of found with dedicated list iterator variable
Posted by Krzysztof Kozlowski 2 years, 9 months ago 
On 12/05/2023 12:19, Jakob Koschel wrote:
> How strange, I just checked and my checkpatch doesn't complain.
> 
> I also redownloaded and double checked 
> (b4 am 20230509-w1-replace-usage-of-found-with-tmp-list-iterator-variable-v2-1-259bf1ba44ed@gmail.com).
> 
> What's the exact issue you are seeing?

  ✓ [PATCH v2] w1: Replace usage of found with dedicated list iterator
variable
    + Link:
https://lore.kernel.org/r/20230509-w1-replace-usage-of-found-with-tmp-list-iterator-variable-v2-1-259bf1ba44ed@gmail.com
    + Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
  ---
  ✗ No key: ed25519/jkl820.git@gmail.com
  ✓ Signed: DKIM/gmail.com
---
Total patches: 1
---
 Base: using specified base-commit eeac8ede17557680855031c6f305ece2378af326
Applying: w1: Replace usage of found with dedicated list iterator variable
[Checking commit]  12b61e664c29 w1: Replace usage of found with
dedicated list iterator variable
[Checkpatch]
CHECK: Alignment should match open parenthesis
#70: FILE: drivers/w1/w1.c:849:
+			if (iter->reg_num.family == id->family &&
+					iter->reg_num.id == id->id &&



Best regards,
Krzysztof
Re: [PATCH v2] w1: Replace usage of found with dedicated list iterator variable
Posted by Jakob Koschel 2 years, 9 months ago 
On 23/05/12 12:26PM, Krzysztof Kozlowski wrote:
> On 12/05/2023 12:19, Jakob Koschel wrote:
> > How strange, I just checked and my checkpatch doesn't complain.
> > 
> > I also redownloaded and double checked 
> > (b4 am 20230509-w1-replace-usage-of-found-with-tmp-list-iterator-variable-v2-1-259bf1ba44ed@gmail.com).
> > 
> > What's the exact issue you are seeing?
> 
>   ✓ [PATCH v2] w1: Replace usage of found with dedicated list iterator
> variable
>     + Link:
> https://lore.kernel.org/r/20230509-w1-replace-usage-of-found-with-tmp-list-iterator-variable-v2-1-259bf1ba44ed@gmail.com
>     + Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>   ---
>   ✗ No key: ed25519/jkl820.git@gmail.com
>   ✓ Signed: DKIM/gmail.com
> ---
> Total patches: 1
> ---
>  Base: using specified base-commit eeac8ede17557680855031c6f305ece2378af326
> Applying: w1: Replace usage of found with dedicated list iterator variable
> [Checking commit]  12b61e664c29 w1: Replace usage of found with
> dedicated list iterator variable
> [Checkpatch]
> CHECK: Alignment should match open parenthesis
> #70: FILE: drivers/w1/w1.c:849:
> +			if (iter->reg_num.family == id->family &&
> +					iter->reg_num.id == id->id &&

I tried a bunch of things but I can't see this message. I tried with 'checkpatch.pl' from different kernel commits.

I did:

  b4 am 20230509-w1-replace-usage-of-found-with-tmp-list-iterator-variable-v2-1-259bf1ba44ed@gmail.com
  scripts/checkpatch.pl ./v2_20230510_jkl820_git_w1_replace_usage_of_found_with_dedicated_list_iterator_variable.mbx

and always get:

  total: 0 errors, 0 warnings, 64 lines checked

  ./v2_20230510_jkl820_git_w1_replace_usage_of_found_with_dedicated_list_iterator_variable.mbx has no obvious style problems and is ready for submission.

I'm out of ideas...

> 
> 
> 
> Best regards,
> Krzysztof
>
Re: [PATCH v2] w1: Replace usage of found with dedicated list iterator variable
Posted by Krzysztof Kozlowski 2 years, 9 months ago 
On 12/05/2023 13:17, Jakob Koschel wrote:
> On 23/05/12 12:26PM, Krzysztof Kozlowski wrote:
>> On 12/05/2023 12:19, Jakob Koschel wrote:
>>> How strange, I just checked and my checkpatch doesn't complain.
>>>
>>> I also redownloaded and double checked 
>>> (b4 am 20230509-w1-replace-usage-of-found-with-tmp-list-iterator-variable-v2-1-259bf1ba44ed@gmail.com).
>>>
>>> What's the exact issue you are seeing?
>>
>>   ✓ [PATCH v2] w1: Replace usage of found with dedicated list iterator
>> variable
>>     + Link:
>> https://lore.kernel.org/r/20230509-w1-replace-usage-of-found-with-tmp-list-iterator-variable-v2-1-259bf1ba44ed@gmail.com
>>     + Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>>   ---
>>   ✗ No key: ed25519/jkl820.git@gmail.com
>>   ✓ Signed: DKIM/gmail.com
>> ---
>> Total patches: 1
>> ---
>>  Base: using specified base-commit eeac8ede17557680855031c6f305ece2378af326
>> Applying: w1: Replace usage of found with dedicated list iterator variable
>> [Checking commit]  12b61e664c29 w1: Replace usage of found with
>> dedicated list iterator variable
>> [Checkpatch]
>> CHECK: Alignment should match open parenthesis
>> #70: FILE: drivers/w1/w1.c:849:
>> +			if (iter->reg_num.family == id->family &&
>> +					iter->reg_num.id == id->id &&
> 
> I tried a bunch of things but I can't see this message. I tried with 'checkpatch.pl' from different kernel commits.
> 
> I did:
> 
>   b4 am 20230509-w1-replace-usage-of-found-with-tmp-list-iterator-variable-v2-1-259bf1ba44ed@gmail.com
>   scripts/checkpatch.pl ./v2_20230510_jkl820_git_w1_replace_usage_of_found_with_dedicated_list_iterator_variable.mbx
> 
> and always get:
> 
>   total: 0 errors, 0 warnings, 64 lines checked
> 
>   ./v2_20230510_jkl820_git_w1_replace_usage_of_found_with_dedicated_list_iterator_variable.mbx has no obvious style problems and is ready for submission.
> 

First - the missing indentation is visible with bare eyes, you can also
fix it without checking in checkpatch.

It seems you are not running checkpatch with --strict. If you want to
see the exact error - run with strict.

Best regards,
Krzysztof
Re: [PATCH v2] w1: Replace usage of found with dedicated list iterator variable
Posted by Jakob Koschel 2 years, 9 months ago 
On 23/05/12 01:23PM, Krzysztof Kozlowski wrote:
> On 12/05/2023 13:17, Jakob Koschel wrote:
> > On 23/05/12 12:26PM, Krzysztof Kozlowski wrote:
> >> On 12/05/2023 12:19, Jakob Koschel wrote:
> >>> How strange, I just checked and my checkpatch doesn't complain.
> >>>
> >>> I also redownloaded and double checked 
> >>> (b4 am 20230509-w1-replace-usage-of-found-with-tmp-list-iterator-variable-v2-1-259bf1ba44ed@gmail.com).
> >>>
> >>> What's the exact issue you are seeing?
> >>
> >>   ✓ [PATCH v2] w1: Replace usage of found with dedicated list iterator
> >> variable
> >>     + Link:
> >> https://lore.kernel.org/r/20230509-w1-replace-usage-of-found-with-tmp-list-iterator-variable-v2-1-259bf1ba44ed@gmail.com
> >>     + Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> >>   ---
> >>   ✗ No key: ed25519/jkl820.git@gmail.com
> >>   ✓ Signed: DKIM/gmail.com
> >> ---
> >> Total patches: 1
> >> ---
> >>  Base: using specified base-commit eeac8ede17557680855031c6f305ece2378af326
> >> Applying: w1: Replace usage of found with dedicated list iterator variable
> >> [Checking commit]  12b61e664c29 w1: Replace usage of found with
> >> dedicated list iterator variable
> >> [Checkpatch]
> >> CHECK: Alignment should match open parenthesis
> >> #70: FILE: drivers/w1/w1.c:849:
> >> +			if (iter->reg_num.family == id->family &&
> >> +					iter->reg_num.id == id->id &&
> > 
> > I tried a bunch of things but I can't see this message. I tried with 'checkpatch.pl' from different kernel commits.
> > 
> > I did:
> > 
> >   b4 am 20230509-w1-replace-usage-of-found-with-tmp-list-iterator-variable-v2-1-259bf1ba44ed@gmail.com
> >   scripts/checkpatch.pl ./v2_20230510_jkl820_git_w1_replace_usage_of_found_with_dedicated_list_iterator_variable.mbx
> > 
> > and always get:
> > 
> >   total: 0 errors, 0 warnings, 64 lines checked
> > 
> >   ./v2_20230510_jkl820_git_w1_replace_usage_of_found_with_dedicated_list_iterator_variable.mbx has no obvious style problems and is ready for submission.
> > 
> 
> First - the missing indentation is visible with bare eyes, you can also
> fix it without checking in checkpatch.

Ah the original code was already wrong and I just kept that way.
Since I'm not frequently contributing and didn't have an error to work with I also didn't know what the correct
way should be.

> 
> It seems you are not running checkpatch with --strict. If you want to
> see the exact error - run with strict.

Thanks, I wasn't aware there is a strict version I should be using.
Good to know for the future.

Not that I can reproduce, I'll fix and send send v3. Sorry about the mess.

> 
> Best regards,
> Krzysztof
>

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