fsnotify: remove destroy_list from fsnotify_mark
destroy_list is used to track marks which still need waiting for srcu
period end before they can be freed. However by the time mark is added to
destroy_list it isn't in group's list of marks anymore and thus we can
reuse fsnotify_mark->g_list for queueing into destroy_list. This saves
two pointers for each fsnotify_mark.
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Eric Paris <eparis@redhat.com>
Cc: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/notify/mark.c b/fs/notify/mark.c
index 3942d5c..92e48c7 100644
--- a/fs/notify/mark.c
+++ b/fs/notify/mark.c
@@ -161,7 +161,7 @@
mutex_unlock(&group->mark_mutex);
spin_lock(&destroy_lock);
- list_add(&mark->destroy_list, &destroy_list);
+ list_add(&mark->g_list, &destroy_list);
spin_unlock(&destroy_lock);
wake_up(&destroy_waitq);
/*
@@ -370,7 +370,7 @@
spin_unlock(&mark->lock);
spin_lock(&destroy_lock);
- list_add(&mark->destroy_list, &destroy_list);
+ list_add(&mark->g_list, &destroy_list);
spin_unlock(&destroy_lock);
wake_up(&destroy_waitq);
@@ -469,8 +469,8 @@
synchronize_srcu(&fsnotify_mark_srcu);
- list_for_each_entry_safe(mark, next, &private_destroy_list, destroy_list) {
- list_del_init(&mark->destroy_list);
+ list_for_each_entry_safe(mark, next, &private_destroy_list, g_list) {
+ list_del_init(&mark->g_list);
fsnotify_put_mark(mark);
}
diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index 442847a..0f313f9 100644
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -212,7 +212,11 @@
* in kernel that found and may be using this mark. */
atomic_t refcnt; /* active things looking at this mark */
struct fsnotify_group *group; /* group this mark is for */
- struct list_head g_list; /* list of marks by group->i_fsnotify_marks */
+ struct list_head g_list; /* list of marks by group->i_fsnotify_marks
+ * Also reused for queueing mark into
+ * destroy_list when it's waiting for
+ * the end of SRCU period before it can
+ * be freed */
spinlock_t lock; /* protect group and inode */
struct hlist_node obj_list; /* list of marks for inode / vfsmount */
struct list_head free_list; /* tmp list used when freeing this mark */
@@ -227,7 +231,6 @@
#define FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY 0x08
#define FSNOTIFY_MARK_FLAG_ALIVE 0x10
unsigned int flags; /* vfsmount or inode mark? */
- struct list_head destroy_list;
void (*free_mark)(struct fsnotify_mark *mark); /* called on final put+free */
};
