2010-12-02 10:03:54

by Lino Sanfilippo

Subject: [PATCH 1/6] fsnotify: introduce new group mutex

This patch intoduces a group specific mutex that is used to synchronize all
group related data/tasks for which no dedicated lock exists yet.

Signed-off-by: Lino Sanfilippo <[email protected]>
---
fs/notify/group.c | 1 +
include/linux/fsnotify_backend.h | 1 +
2 files changed, 2 insertions(+), 0 deletions(-)

Please apply this against commit 9f71741c75e5206e1fea72ddf2adf5661105444d of
branch 'origin/for-next' from git.infradead.org/users/eparis/notify.git

Eric, as you can see i chose to introduce a new mutex instead of using the
notification_mutex since you may be right with you concerns about performance.
I guess its ok since its what you preferred.

diff --git a/fs/notify/group.c b/fs/notify/group.c
index d309f38..cc341d3 100644
--- a/fs/notify/group.c
+++ b/fs/notify/group.c
@@ -90,6 +90,7 @@ struct fsnotify_group *fsnotify_alloc_group(const struct fsnotify_ops *ops)
*/
atomic_set(&group->num_marks, 1);

+ mutex_init(&group->mutex);
mutex_init(&group->notification_mutex);
INIT_LIST_HEAD(&group->notification_list);
init_waitqueue_head(&group->notification_waitq);
diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index add1351..6a3c660 100644
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -125,6 +125,7 @@ struct fsnotify_group {

const struct fsnotify_ops *ops; /* how this group handles things */

+ struct mutex mutex;
/* needed to send notification to userspace */
struct mutex notification_mutex; /* protect the notification_list */
struct list_head notification_list; /* list of event_holder this group needs to send to userspace */
--
1.5.6.5

2010-12-07 19:56:21

by Eric Paris

Subject: Re: [PATCH 1/6] fsnotify: introduce new group mutex

On Thu, 2010-12-02 at 11:01 +0100, Lino Sanfilippo wrote:
> This patch intoduces a group specific mutex that is used to synchronize all
> group related data/tasks for which no dedicated lock exists yet.
>
> Signed-off-by: Lino Sanfilippo <[email protected]>

Patch 1-4 applied to for-next;