Commit 139ca04e authored by Jeff Layton's avatar Jeff Layton Committed by Al Viro

locks: convert fl_link to a hlist_node

Testing has shown that iterating over the blocked_list for deadlock
detection turns out to be a bottleneck. In order to alleviate that,
begin the process of turning it into a hashtable. We start by turning
the fl_link into a hlist_node and the global lists into hlists. A later
patch will do the conversion of the blocked_list to a hashtable.
Signed-off-by: default avatarJeff Layton <jlayton@redhat.com>
Acked-by: default avatarJ. Bruce Fields <bfields@fieldses.org>
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 4e8c765d
...@@ -157,13 +157,13 @@ int lease_break_time = 45; ...@@ -157,13 +157,13 @@ int lease_break_time = 45;
* The global file_lock_list is only used for displaying /proc/locks. Protected * The global file_lock_list is only used for displaying /proc/locks. Protected
* by the file_lock_lock. * by the file_lock_lock.
*/ */
static LIST_HEAD(file_lock_list); static HLIST_HEAD(file_lock_list);
/* /*
* The blocked_list is used to find POSIX lock loops for deadlock detection. * The blocked_list is used to find POSIX lock loops for deadlock detection.
* Protected by file_lock_lock. * Protected by file_lock_lock.
*/ */
static LIST_HEAD(blocked_list); static HLIST_HEAD(blocked_list);
/* /*
* This lock protects the blocked_list, and the file_lock_list. Generally, if * This lock protects the blocked_list, and the file_lock_list. Generally, if
...@@ -188,7 +188,7 @@ static struct kmem_cache *filelock_cache __read_mostly; ...@@ -188,7 +188,7 @@ static struct kmem_cache *filelock_cache __read_mostly;
static void locks_init_lock_heads(struct file_lock *fl) static void locks_init_lock_heads(struct file_lock *fl)
{ {
INIT_LIST_HEAD(&fl->fl_link); INIT_HLIST_NODE(&fl->fl_link);
INIT_LIST_HEAD(&fl->fl_block); INIT_LIST_HEAD(&fl->fl_block);
init_waitqueue_head(&fl->fl_wait); init_waitqueue_head(&fl->fl_wait);
} }
...@@ -222,7 +222,7 @@ void locks_free_lock(struct file_lock *fl) ...@@ -222,7 +222,7 @@ void locks_free_lock(struct file_lock *fl)
{ {
BUG_ON(waitqueue_active(&fl->fl_wait)); BUG_ON(waitqueue_active(&fl->fl_wait));
BUG_ON(!list_empty(&fl->fl_block)); BUG_ON(!list_empty(&fl->fl_block));
BUG_ON(!list_empty(&fl->fl_link)); BUG_ON(!hlist_unhashed(&fl->fl_link));
locks_release_private(fl); locks_release_private(fl);
kmem_cache_free(filelock_cache, fl); kmem_cache_free(filelock_cache, fl);
...@@ -500,7 +500,7 @@ static inline void ...@@ -500,7 +500,7 @@ static inline void
locks_insert_global_locks(struct file_lock *fl) locks_insert_global_locks(struct file_lock *fl)
{ {
spin_lock(&file_lock_lock); spin_lock(&file_lock_lock);
list_add_tail(&fl->fl_link, &file_lock_list); hlist_add_head(&fl->fl_link, &file_lock_list);
spin_unlock(&file_lock_lock); spin_unlock(&file_lock_lock);
} }
...@@ -508,20 +508,20 @@ static inline void ...@@ -508,20 +508,20 @@ static inline void
locks_delete_global_locks(struct file_lock *fl) locks_delete_global_locks(struct file_lock *fl)
{ {
spin_lock(&file_lock_lock); spin_lock(&file_lock_lock);
list_del_init(&fl->fl_link); hlist_del_init(&fl->fl_link);
spin_unlock(&file_lock_lock); spin_unlock(&file_lock_lock);
} }
static inline void static inline void
locks_insert_global_blocked(struct file_lock *waiter) locks_insert_global_blocked(struct file_lock *waiter)
{ {
list_add(&waiter->fl_link, &blocked_list); hlist_add_head(&waiter->fl_link, &blocked_list);
} }
static inline void static inline void
locks_delete_global_blocked(struct file_lock *waiter) locks_delete_global_blocked(struct file_lock *waiter)
{ {
list_del_init(&waiter->fl_link); hlist_del_init(&waiter->fl_link);
} }
/* Remove waiter from blocker's block list. /* Remove waiter from blocker's block list.
...@@ -748,7 +748,7 @@ static struct file_lock *what_owner_is_waiting_for(struct file_lock *block_fl) ...@@ -748,7 +748,7 @@ static struct file_lock *what_owner_is_waiting_for(struct file_lock *block_fl)
{ {
struct file_lock *fl; struct file_lock *fl;
list_for_each_entry(fl, &blocked_list, fl_link) { hlist_for_each_entry(fl, &blocked_list, fl_link) {
if (posix_same_owner(fl, block_fl)) if (posix_same_owner(fl, block_fl))
return fl->fl_next; return fl->fl_next;
} }
...@@ -2300,7 +2300,7 @@ static int locks_show(struct seq_file *f, void *v) ...@@ -2300,7 +2300,7 @@ static int locks_show(struct seq_file *f, void *v)
{ {
struct file_lock *fl, *bfl; struct file_lock *fl, *bfl;
fl = list_entry(v, struct file_lock, fl_link); fl = hlist_entry(v, struct file_lock, fl_link);
lock_get_status(f, fl, *((loff_t *)f->private), ""); lock_get_status(f, fl, *((loff_t *)f->private), "");
...@@ -2316,14 +2316,14 @@ static void *locks_start(struct seq_file *f, loff_t *pos) ...@@ -2316,14 +2316,14 @@ static void *locks_start(struct seq_file *f, loff_t *pos)
spin_lock(&file_lock_lock); spin_lock(&file_lock_lock);
*p = (*pos + 1); *p = (*pos + 1);
return seq_list_start(&file_lock_list, *pos); return seq_hlist_start(&file_lock_list, *pos);
} }
static void *locks_next(struct seq_file *f, void *v, loff_t *pos) static void *locks_next(struct seq_file *f, void *v, loff_t *pos)
{ {
loff_t *p = f->private; loff_t *p = f->private;
++*p; ++*p;
return seq_list_next(v, &file_lock_list, pos); return seq_hlist_next(v, &file_lock_list, pos);
} }
static void locks_stop(struct seq_file *f, void *v) static void locks_stop(struct seq_file *f, void *v)
......
...@@ -946,7 +946,7 @@ int locks_in_grace(struct net *); ...@@ -946,7 +946,7 @@ int locks_in_grace(struct net *);
*/ */
struct file_lock { struct file_lock {
struct file_lock *fl_next; /* singly linked list for this inode */ struct file_lock *fl_next; /* singly linked list for this inode */
struct list_head fl_link; /* doubly linked list of all locks */ struct hlist_node fl_link; /* node in global lists */
struct list_head fl_block; /* circular list of blocked processes */ struct list_head fl_block; /* circular list of blocked processes */
fl_owner_t fl_owner; fl_owner_t fl_owner;
unsigned int fl_flags; unsigned int fl_flags;
......
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