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[PATCH mptcp-net v2 3/3] mptcp: pm: avoid code duplication to lookup endp

Matthieu Baerts (NGI0) posted 3 patches 1 year, 3 months ago
There is a newer version of this series
[PATCH mptcp-net v2 3/3] mptcp: pm: avoid code duplication to lookup endp
Posted by Matthieu Baerts (NGI0) 1 year, 3 months ago 
From: Geliang Tang <tanggeliang@kylinos.cn>

The helper __lookup_addr_rcu() can be used in mptcp_pm_nl_get_local_id()
and mptcp_pm_nl_is_backup() to simplify the code, and avoid code
duplication.

Co-developed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
Notes:
 - This is also for -next.
---
 net/mptcp/pm_netlink.c | 20 ++++++--------------
 1 file changed, 6 insertions(+), 14 deletions(-)

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index f38e1ccd34e95cd88b179a8b50e6965731542871..7c6e664b236d1659a554d003c78c72ec91895ba5 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -1154,17 +1154,13 @@ int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc
 {
 	struct mptcp_pm_addr_entry *entry;
 	struct pm_nl_pernet *pernet;
-	int ret = -1;
+	int ret;
 
 	pernet = pm_nl_get_pernet_from_msk(msk);
 
 	rcu_read_lock();
-	list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
-		if (mptcp_addresses_equal(&entry->addr, skc, entry->addr.port)) {
-			ret = entry->addr.id;
-			break;
-		}
-	}
+	entry = __lookup_addr_rcu(pernet, skc);
+	ret = entry ? entry->addr.id : -1;
 	rcu_read_unlock();
 	if (ret >= 0)
 		return ret;
@@ -1191,15 +1187,11 @@ bool mptcp_pm_nl_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc)
 {
 	struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk);
 	struct mptcp_pm_addr_entry *entry;
-	bool backup = false;
+	bool backup;
 
 	rcu_read_lock();
-	list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
-		if (mptcp_addresses_equal(&entry->addr, skc, entry->addr.port)) {
-			backup = !!(entry->flags & MPTCP_PM_ADDR_FLAG_BACKUP);
-			break;
-		}
-	}
+	entry = __lookup_addr_rcu(pernet, skc);
+	backup = entry && !!(entry->flags & MPTCP_PM_ADDR_FLAG_BACKUP);
 	rcu_read_unlock();
 
 	return backup;

-- 
2.45.2
Re: [PATCH mptcp-net v2 3/3] mptcp: pm: avoid code duplication to lookup endp
Posted by Geliang Tang 1 year, 3 months ago 
Hi Matt,

Thanks for this patch.

On Fri, 2024-10-25 at 11:32 +0200, Matthieu Baerts (NGI0) wrote:
> From: Geliang Tang <tanggeliang@kylinos.cn>
> 
> The helper __lookup_addr_rcu() can be used in
> mptcp_pm_nl_get_local_id()
> and mptcp_pm_nl_is_backup() to simplify the code, and avoid code
> duplication.
> 
> Co-developed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
> Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
> ---
> Notes:
>  - This is also for -next.
> ---
>  net/mptcp/pm_netlink.c | 20 ++++++--------------
>  1 file changed, 6 insertions(+), 14 deletions(-)
> 
> diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
> index
> f38e1ccd34e95cd88b179a8b50e6965731542871..7c6e664b236d1659a554d003c78
> c72ec91895ba5 100644
> --- a/net/mptcp/pm_netlink.c
> +++ b/net/mptcp/pm_netlink.c
> @@ -1154,17 +1154,13 @@ int mptcp_pm_nl_get_local_id(struct
> mptcp_sock *msk, struct mptcp_addr_info *skc
>  {
>  	struct mptcp_pm_addr_entry *entry;
>  	struct pm_nl_pernet *pernet;
> -	int ret = -1;
> +	int ret;
>  
>  	pernet = pm_nl_get_pernet_from_msk(msk);
>  
>  	rcu_read_lock();
> -	list_for_each_entry_rcu(entry, &pernet->local_addr_list,
> list) {
> -		if (mptcp_addresses_equal(&entry->addr, skc, entry-
> >addr.port)) {
> -			ret = entry->addr.id;
> -			break;
> -		}
> -	}
> +	entry = __lookup_addr_rcu(pernet, skc);
> +	ret = entry ? entry->addr.id : -1;
>  	rcu_read_unlock();
>  	if (ret >= 0)
>  		return ret;
> @@ -1191,15 +1187,11 @@ bool mptcp_pm_nl_is_backup(struct mptcp_sock
> *msk, struct mptcp_addr_info *skc)
>  {
>  	struct pm_nl_pernet *pernet =
> pm_nl_get_pernet_from_msk(msk);
>  	struct mptcp_pm_addr_entry *entry;
> -	bool backup = false;
> +	bool backup;
>  
>  	rcu_read_lock();
> -	list_for_each_entry_rcu(entry, &pernet->local_addr_list,
> list) {
> -		if (mptcp_addresses_equal(&entry->addr, skc, entry-
> >addr.port)) {
> -			backup = !!(entry->flags &
> MPTCP_PM_ADDR_FLAG_BACKUP);
> -			break;
> -		}
> -	}
> +	entry = __lookup_addr_rcu(pernet, skc);
> +	backup = entry && !!(entry->flags &
> MPTCP_PM_ADDR_FLAG_BACKUP);

I think we should check whether entry is NULL here too. No?

-Geliang

>  	rcu_read_unlock();
>  
>  	return backup;
>
Re: [PATCH mptcp-net v2 3/3] mptcp: pm: avoid code duplication to lookup endp
Posted by Geliang Tang 1 year, 3 months ago 
On Fri, 2024-10-25 at 18:37 +0800, Geliang Tang wrote:
> Hi Matt,
> 
> Thanks for this patch.
> 
> On Fri, 2024-10-25 at 11:32 +0200, Matthieu Baerts (NGI0) wrote:
> > From: Geliang Tang <tanggeliang@kylinos.cn>
> > 
> > The helper __lookup_addr_rcu() can be used in
> > mptcp_pm_nl_get_local_id()
> > and mptcp_pm_nl_is_backup() to simplify the code, and avoid code
> > duplication.
> > 
> > Co-developed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
> > Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
> > Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
> > ---
> > Notes:
> >  - This is also for -next.
> > ---
> >  net/mptcp/pm_netlink.c | 20 ++++++--------------
> >  1 file changed, 6 insertions(+), 14 deletions(-)
> > 
> > diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
> > index
> > f38e1ccd34e95cd88b179a8b50e6965731542871..7c6e664b236d1659a554d003c
> > 78
> > c72ec91895ba5 100644
> > --- a/net/mptcp/pm_netlink.c
> > +++ b/net/mptcp/pm_netlink.c
> > @@ -1154,17 +1154,13 @@ int mptcp_pm_nl_get_local_id(struct
> > mptcp_sock *msk, struct mptcp_addr_info *skc
> >  {
> >  	struct mptcp_pm_addr_entry *entry;
> >  	struct pm_nl_pernet *pernet;
> > -	int ret = -1;
> > +	int ret;
> >  
> >  	pernet = pm_nl_get_pernet_from_msk(msk);
> >  
> >  	rcu_read_lock();
> > -	list_for_each_entry_rcu(entry, &pernet->local_addr_list,
> > list) {
> > -		if (mptcp_addresses_equal(&entry->addr, skc,
> > entry-
> > > addr.port)) {
> > -			ret = entry->addr.id;
> > -			break;
> > -		}
> > -	}
> > +	entry = __lookup_addr_rcu(pernet, skc);
> > +	ret = entry ? entry->addr.id : -1;
> >  	rcu_read_unlock();
> >  	if (ret >= 0)
> >  		return ret;
> > @@ -1191,15 +1187,11 @@ bool mptcp_pm_nl_is_backup(struct
> > mptcp_sock
> > *msk, struct mptcp_addr_info *skc)
> >  {
> >  	struct pm_nl_pernet *pernet =
> > pm_nl_get_pernet_from_msk(msk);
> >  	struct mptcp_pm_addr_entry *entry;
> > -	bool backup = false;
> > +	bool backup;
> >  
> >  	rcu_read_lock();
> > -	list_for_each_entry_rcu(entry, &pernet->local_addr_list,
> > list) {
> > -		if (mptcp_addresses_equal(&entry->addr, skc,
> > entry-
> > > addr.port)) {
> > -			backup = !!(entry->flags &
> > MPTCP_PM_ADDR_FLAG_BACKUP);
> > -			break;
> > -		}
> > -	}
> > +	entry = __lookup_addr_rcu(pernet, skc);
> > +	backup = entry && !!(entry->flags &
> > MPTCP_PM_ADDR_FLAG_BACKUP);
> 
> I think we should check whether entry is NULL here too. No?

Sorry, ignore my comment, your code is correct. :)

-Geliang

> 
> -Geliang
> 
> >  	rcu_read_unlock();
> >  
> >  	return backup;
> > 
> 
>
Re: [PATCH mptcp-net v2 3/3] mptcp: pm: avoid code duplication to lookup endp
Posted by Matthieu Baerts 1 year, 3 months ago 
Hi Geliang,

Thank you for the review!

On 25/10/2024 12:37, Geliang Tang wrote:
> On Fri, 2024-10-25 at 11:32 +0200, Matthieu Baerts (NGI0) wrote:
>> From: Geliang Tang <tanggeliang@kylinos.cn>
>>
>> The helper __lookup_addr_rcu() can be used in
>> mptcp_pm_nl_get_local_id()
>> and mptcp_pm_nl_is_backup() to simplify the code, and avoid code
>> duplication.

(...)

>> diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
>> index
>> f38e1ccd34e95cd88b179a8b50e6965731542871..7c6e664b236d1659a554d003c78
>> c72ec91895ba5 100644
>> --- a/net/mptcp/pm_netlink.c
>> +++ b/net/mptcp/pm_netlink.c

(...)

>> @@ -1191,15 +1187,11 @@ bool mptcp_pm_nl_is_backup(struct mptcp_sock
>> *msk, struct mptcp_addr_info *skc)
>>  {
>>  	struct pm_nl_pernet *pernet =
>> pm_nl_get_pernet_from_msk(msk);
>>  	struct mptcp_pm_addr_entry *entry;
>> -	bool backup = false;
>> +	bool backup;
>>  
>>  	rcu_read_lock();
>> -	list_for_each_entry_rcu(entry, &pernet->local_addr_list,
>> list) {
>> -		if (mptcp_addresses_equal(&entry->addr, skc, entry-
>>> addr.port)) {
>> -			backup = !!(entry->flags &
>> MPTCP_PM_ADDR_FLAG_BACKUP);
>> -			break;
>> -		}
>> -	}
>> +	entry = __lookup_addr_rcu(pernet, skc);
>> +	backup = entry && !!(entry->flags &
>> MPTCP_PM_ADDR_FLAG_BACKUP);
> 
> I think we should check whether entry is NULL here too. No?

Yes, but that's what I did, no?

  backup = entry && (entry->flags & BACKUP)

"backup" is set to "true" if entry is not NULL and the backup flag is set.

Cheers,
Matt
-- 
Sponsored by the NGI0 Core fund.

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