diff mbox series

IB/SA: replace usage of found with dedicated list iterator variable

Message ID 20220324071124.59849-1-jakobkoschel@gmail.com (mailing list archive)
State Superseded
Delegated to: Jason Gunthorpe
Headers show
Series IB/SA: replace usage of found with dedicated list iterator variable | expand

Commit Message

Jakob Koschel March 24, 2022, 7:11 a.m. UTC 
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 <jakobkoschel@gmail.com>
---
 drivers/infiniband/core/sa_query.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)


base-commit: f443e374ae131c168a065ea1748feac6b2e76613

Comments

Mark Zhang March 24, 2022, 7:53 a.m. UTC | #1 
On 3/24/2022 3:11 PM, Jakob Koschel wrote:
> External email: Use caution opening links or attachments
> 
> 
> 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 <jakobkoschel@gmail.com>
> ---
>   drivers/infiniband/core/sa_query.c | 15 +++++++--------
>   1 file changed, 7 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/infiniband/core/sa_query.c b/drivers/infiniband/core/sa_query.c
> index 74ecd7456a11..74cd84045e5b 100644
> --- a/drivers/infiniband/core/sa_query.c
> +++ b/drivers/infiniband/core/sa_query.c
> @@ -1035,10 +1035,9 @@ int ib_nl_handle_resolve_resp(struct sk_buff *skb,
>                                struct netlink_ext_ack *extack)
>   {
>          unsigned long flags;
> -       struct ib_sa_query *query;
> +       struct ib_sa_query *query = NULL, *iter;
>          struct ib_mad_send_buf *send_buf;
>          struct ib_mad_send_wc mad_send_wc;
> -       int found = 0;
>          int ret;
> 
>          if ((nlh->nlmsg_flags & NLM_F_REQUEST) ||
> @@ -1046,20 +1045,20 @@ int ib_nl_handle_resolve_resp(struct sk_buff *skb,
>                  return -EPERM;
> 
>          spin_lock_irqsave(&ib_nl_request_lock, flags);
> -       list_for_each_entry(query, &ib_nl_request_list, list) {
> +       list_for_each_entry(iter, &ib_nl_request_list, list) {
>                  /*
>                   * If the query is cancelled, let the timeout routine
>                   * take care of it.
>                   */
> -               if (nlh->nlmsg_seq == query->seq) {
> -                       found = !ib_sa_query_cancelled(query);
> -                       if (found)
> -                               list_del(&query->list);
> +               if (nlh->nlmsg_seq == iter->seq) {
> +                       if (!ib_sa_query_cancelled(iter))
> +                               list_del(&iter->list);
> +                       query = iter;
>                          break;

Should it be:

if (nlh->nlmsg_seq == iter->seq) {
	if (!ib_sa_query_cancelled(iter)) {
		list_del(&iter->list);
		query = iter;
	}
	break;

>                  }
>          }
> 
> -       if (!found) {
> +       if (!query) {
>                  spin_unlock_irqrestore(&ib_nl_request_lock, flags);
>                  goto resp_out;
>          }
> 
> base-commit: f443e374ae131c168a065ea1748feac6b2e76613
> --
> 2.25.1
>
Jakob Koschel March 24, 2022, 8:24 a.m. UTC | #2 
> On 24. Mar 2022, at 08:53, Mark Zhang <markzhang@nvidia.com> wrote:
> 
> On 3/24/2022 3:11 PM, Jakob Koschel wrote:
>> External email: Use caution opening links or attachments
>> 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 <jakobkoschel@gmail.com>
>> ---
>> drivers/infiniband/core/sa_query.c | 15 +++++++--------
>> 1 file changed, 7 insertions(+), 8 deletions(-)
>> diff --git a/drivers/infiniband/core/sa_query.c b/drivers/infiniband/core/sa_query.c
>> index 74ecd7456a11..74cd84045e5b 100644
>> --- a/drivers/infiniband/core/sa_query.c
>> +++ b/drivers/infiniband/core/sa_query.c
>> @@ -1035,10 +1035,9 @@ int ib_nl_handle_resolve_resp(struct sk_buff *skb,
>> struct netlink_ext_ack *extack)
>> {
>> unsigned long flags;
>> - struct ib_sa_query *query;
>> + struct ib_sa_query *query = NULL, *iter;
>> struct ib_mad_send_buf *send_buf;
>> struct ib_mad_send_wc mad_send_wc;
>> - int found = 0;
>> int ret;
>> if ((nlh->nlmsg_flags & NLM_F_REQUEST) ||
>> @@ -1046,20 +1045,20 @@ int ib_nl_handle_resolve_resp(struct sk_buff *skb,
>> return -EPERM;
>> spin_lock_irqsave(&ib_nl_request_lock, flags);
>> - list_for_each_entry(query, &ib_nl_request_list, list) {
>> + list_for_each_entry(iter, &ib_nl_request_list, list) {
>> /*
>> * If the query is cancelled, let the timeout routine
>> * take care of it.
>> */
>> - if (nlh->nlmsg_seq == query->seq) {
>> - found = !ib_sa_query_cancelled(query);
>> - if (found)
>> - list_del(&query->list);
>> + if (nlh->nlmsg_seq == iter->seq) {
>> + if (!ib_sa_query_cancelled(iter))
>> + list_del(&iter->list);
>> + query = iter;
>> break;
> 
> Should it be:
> 
> if (nlh->nlmsg_seq == iter->seq) {
> 	if (!ib_sa_query_cancelled(iter)) {
> 		list_del(&iter->list);
> 		query = iter;
> 	}
> 	break;

yes you are right. Sorry about that, I'll send a fixed version with v2.

> 
>> }
>> }
>> - if (!found) {
>> + if (!query) {
>> spin_unlock_irqrestore(&ib_nl_request_lock, flags);
>> goto resp_out;
>> }
>> base-commit: f443e374ae131c168a065ea1748feac6b2e76613
>> --
>> 2.25.1
diff mbox series

Patch

diff --git a/drivers/infiniband/core/sa_query.c b/drivers/infiniband/core/sa_query.c
index 74ecd7456a11..74cd84045e5b 100644
--- a/drivers/infiniband/core/sa_query.c
+++ b/drivers/infiniband/core/sa_query.c
@@ -1035,10 +1035,9 @@  int ib_nl_handle_resolve_resp(struct sk_buff *skb,
 			      struct netlink_ext_ack *extack)
 {
 	unsigned long flags;
-	struct ib_sa_query *query;
+	struct ib_sa_query *query = NULL, *iter;
 	struct ib_mad_send_buf *send_buf;
 	struct ib_mad_send_wc mad_send_wc;
-	int found = 0;
 	int ret;
 
 	if ((nlh->nlmsg_flags & NLM_F_REQUEST) ||
@@ -1046,20 +1045,20 @@  int ib_nl_handle_resolve_resp(struct sk_buff *skb,
 		return -EPERM;
 
 	spin_lock_irqsave(&ib_nl_request_lock, flags);
-	list_for_each_entry(query, &ib_nl_request_list, list) {
+	list_for_each_entry(iter, &ib_nl_request_list, list) {
 		/*
 		 * If the query is cancelled, let the timeout routine
 		 * take care of it.
 		 */
-		if (nlh->nlmsg_seq == query->seq) {
-			found = !ib_sa_query_cancelled(query);
-			if (found)
-				list_del(&query->list);
+		if (nlh->nlmsg_seq == iter->seq) {
+			if (!ib_sa_query_cancelled(iter))
+				list_del(&iter->list);
+			query = iter;
 			break;
 		}
 	}
 
-	if (!found) {
+	if (!query) {
 		spin_unlock_irqrestore(&ib_nl_request_lock, flags);
 		goto resp_out;
 	}