path: root/include/linux/fs.h
diff options
authorJeff Layton <jlayton@redhat.com>2013-06-21 08:58:22 -0400
committerAl Viro <viro@zeniv.linux.org.uk>2013-07-08 13:36:42 +0400
commit7012b02a2b2c42bb1e1d95040a6e3bb59c7284f7 (patch)
tree6a1c54cdca608ad75db6282cc4c0c7a6bb5f7673 /include/linux/fs.h
parent0bc77381c1b1600e659eb7322c39d1753615722d (diff)
locks: move file_lock_list to a set of percpu hlist_heads and convert file_lock_lock to an lglock
The file_lock_list is only used for /proc/locks. The vastly common case is for locks to be put onto the list and come off again, without ever being traversed. Help optimize for this use-case by moving to percpu hlist_head-s. At the same time, we can make the locking less contentious by moving to an lglock. When iterating over the lists for /proc/locks, we must take the global lock and then iterate over each CPU's list in turn. This change necessitates a new fl_link_cpu field to keep track of which CPU the entry is on. On x86_64 at least, this field is placed within an existing hole in the struct to avoid growing the size. Signed-off-by: Jeff Layton <jlayton@redhat.com> Acked-by: J. Bruce Fields <bfields@fieldses.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'include/linux/fs.h')
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 99be011e00de..834c9e5113d9 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -954,6 +954,7 @@ struct file_lock {
unsigned int fl_flags;
unsigned char fl_type;
unsigned int fl_pid;
+ int fl_link_cpu; /* what cpu's list is this on? */
struct pid *fl_nspid;
wait_queue_head_t fl_wait;
struct file *fl_file;