2015-04-13 14:14:26

by Lukasz Skalski

Subject: [PATCH] kdbus: do not append the same connection to the queue twice

As it was discussed on systemd ML [1], the same connection should be
queued up only once for a given well-known name.

[1] http://lists.freedesktop.org/archives/systemd-devel/2015-April/030494.html

Signed-off-by: Lukasz Skalski <[email protected]>

diff --git a/ipc/kdbus/names.c b/ipc/kdbus/names.c
index 657008e..a546a84 100644
--- a/ipc/kdbus/names.c
+++ b/ipc/kdbus/names.c
@@ -353,10 +353,23 @@ int kdbus_name_acquire(struct kdbus_name_registry *reg,
} else if (flags & KDBUS_NAME_QUEUE) {
/* add to waiting-queue of the name */

- ret = kdbus_name_pending_new(e, conn, flags);
- if (ret >= 0)
- /* tell the caller that we queued it */
- rflags |= KDBUS_NAME_IN_QUEUE;
+ struct kdbus_name_pending *p;
+ bool in_queue = false;
+
+ list_for_each_entry(p, &e->queue, name_entry) {
+ if (p->conn == conn) {
+ /* connection is already queued */
+ rflags |= KDBUS_NAME_IN_QUEUE;
+ in_queue = true;
+ }
+ }
+
+ if (!in_queue) {
+ ret = kdbus_name_pending_new(e, conn, flags);
+ if (ret >= 0)
+ /* tell the caller that we queued it */
+ rflags |= KDBUS_NAME_IN_QUEUE;
+ }
} else {
/* the name is busy, return a failure */
ret = -EEXIST;
--
1.9.3

2015-04-13 21:48:40

by Sergei Zviagintsev

Subject: Re: [PATCH] kdbus: do not append the same connection to the queue twice

Hi Lukasz,

On Mon, Apr 13, 2015 at 04:14:06PM +0200, Lukasz Skalski wrote:
> As it was discussed on systemd ML [1], the same connection should be
> queued up only once for a given well-known name.
>
> [1] http://lists.freedesktop.org/archives/systemd-devel/2015-April/030494.html
>
> Signed-off-by: Lukasz Skalski <[email protected]>
>
> diff --git a/ipc/kdbus/names.c b/ipc/kdbus/names.c
> index 657008e..a546a84 100644
> --- a/ipc/kdbus/names.c
> +++ b/ipc/kdbus/names.c
> @@ -353,10 +353,23 @@ int kdbus_name_acquire(struct kdbus_name_registry *reg,
> } else if (flags & KDBUS_NAME_QUEUE) {
> /* add to waiting-queue of the name */
>
> - ret = kdbus_name_pending_new(e, conn, flags);
> - if (ret >= 0)
> - /* tell the caller that we queued it */
> - rflags |= KDBUS_NAME_IN_QUEUE;
> + struct kdbus_name_pending *p;
> + bool in_queue = false;
> +
> + list_for_each_entry(p, &e->queue, name_entry) {
> + if (p->conn == conn) {
> + /* connection is already queued */
> + rflags |= KDBUS_NAME_IN_QUEUE;
> + in_queue = true;

break here?

> + }
> + }
> +
> + if (!in_queue) {
> + ret = kdbus_name_pending_new(e, conn, flags);
> + if (ret >= 0)
> + /* tell the caller that we queued it */
> + rflags |= KDBUS_NAME_IN_QUEUE;
> + }
> } else {
> /* the name is busy, return a failure */
> ret = -EEXIST;
> --
> 1.9.3
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/

2015-04-14 08:27:47

by Lukasz Skalski

Subject: Re: [PATCH] kdbus: do not append the same connection to the queue twice

On 04/13/2015 11:48 PM, Sergei Zviagintsev wrote:
> Hi Lukasz,
>

Hi,

> On Mon, Apr 13, 2015 at 04:14:06PM +0200, Lukasz Skalski wrote:
>> As it was discussed on systemd ML [1], the same connection should be
>> queued up only once for a given well-known name.
>>
>> [1] http://lists.freedesktop.org/archives/systemd-devel/2015-April/030494.html
>>
>> Signed-off-by: Lukasz Skalski <[email protected]>
>>
>> diff --git a/ipc/kdbus/names.c b/ipc/kdbus/names.c
>> index 657008e..a546a84 100644
>> --- a/ipc/kdbus/names.c
>> +++ b/ipc/kdbus/names.c
>> @@ -353,10 +353,23 @@ int kdbus_name_acquire(struct kdbus_name_registry *reg,
>> } else if (flags & KDBUS_NAME_QUEUE) {
>> /* add to waiting-queue of the name */
>>
>> - ret = kdbus_name_pending_new(e, conn, flags);
>> - if (ret >= 0)
>> - /* tell the caller that we queued it */
>> - rflags |= KDBUS_NAME_IN_QUEUE;
>> + struct kdbus_name_pending *p;
>> + bool in_queue = false;
>> +
>> + list_for_each_entry(p, &e->queue, name_entry) {
>> + if (p->conn == conn) {
>> + /* connection is already queued */
>> + rflags |= KDBUS_NAME_IN_QUEUE;
>> + in_queue = true;
>
> break here?
>

Right. I've just sent v2. Thanks!

>> + }
>> + }
>> +
>> + if (!in_queue) {
>> + ret = kdbus_name_pending_new(e, conn, flags);
>> + if (ret >= 0)
>> + /* tell the caller that we queued it */
>> + rflags |= KDBUS_NAME_IN_QUEUE;
>> + }
>> } else {
>> /* the name is busy, return a failure */
>> ret = -EEXIST;
>> --
>> 1.9.3
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to [email protected]
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at http://www.tux.org/lkml/
>

Cheers,
--
Lukasz Skalski
Samsung R&D Institute Poland
Samsung Electronics
[email protected]