locks: keep a count of locks on the flctx lists
authorJeff Layton <jlayton@primarydata.com>
Fri, 16 Jan 2015 20:05:57 +0000 (15:05 -0500)
committerJeff Layton <jeff.layton@primarydata.com>
Fri, 16 Jan 2015 21:08:50 +0000 (16:08 -0500)
This makes things a bit more efficient in the cifs and ceph lock
pushing code.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Acked-by: Christoph Hellwig <hch@lst.de>
fs/ceph/locks.c
fs/cifs/file.c
fs/locks.c
include/linux/fs.h

index 0303da8e3233180bf9da1b82ff7fa440a8df35c8..06ea5cd05cd9ebcf47161b813fc0a39472911b93 100644 (file)
@@ -242,12 +242,9 @@ int ceph_flock(struct file *file, int cmd, struct file_lock *fl)
 /*
  * Fills in the passed counter variables, so you can prepare pagelist metadata
  * before calling ceph_encode_locks.
- *
- * FIXME: add counters to struct file_lock_context so we don't need to do this?
  */
 void ceph_count_locks(struct inode *inode, int *fcntl_count, int *flock_count)
 {
-       struct file_lock *lock;
        struct file_lock_context *ctx;
 
        *fcntl_count = 0;
@@ -255,12 +252,8 @@ void ceph_count_locks(struct inode *inode, int *fcntl_count, int *flock_count)
 
        ctx = inode->i_flctx;
        if (ctx) {
-               spin_lock(&ctx->flc_lock);
-               list_for_each_entry(lock, &ctx->flc_posix, fl_list)
-                       ++(*fcntl_count);
-               list_for_each_entry(lock, &ctx->flc_flock, fl_list)
-                       ++(*flock_count);
-               spin_unlock(&ctx->flc_lock);
+               *fcntl_count = ctx->flc_posix_cnt;
+               *flock_count = ctx->flc_flock_cnt;
        }
        dout("counted %d flock locks and %d fcntl locks",
             *flock_count, *fcntl_count);
index b65166eb111ee7b8c2f538c68440c37469e2d39d..8c2ca6f62bad093bfcbf4586c32fe8c505a92730 100644 (file)
@@ -1125,7 +1125,7 @@ cifs_push_posix_locks(struct cifsFileInfo *cfile)
        struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
        struct file_lock *flock;
        struct file_lock_context *flctx = inode->i_flctx;
-       unsigned int count = 0, i;
+       unsigned int i;
        int rc = 0, xid, type;
        struct list_head locks_to_send, *el;
        struct lock_to_push *lck, *tmp;
@@ -1136,20 +1136,14 @@ cifs_push_posix_locks(struct cifsFileInfo *cfile)
        if (!flctx)
                goto out;
 
-       spin_lock(&flctx->flc_lock);
-       list_for_each(el, &flctx->flc_posix) {
-               count++;
-       }
-       spin_unlock(&flctx->flc_lock);
-
        INIT_LIST_HEAD(&locks_to_send);
 
        /*
-        * Allocating count locks is enough because no FL_POSIX locks can be
-        * added to the list while we are holding cinode->lock_sem that
+        * Allocating flc_posix_cnt locks is enough because no FL_POSIX locks
+        * can be added to the list while we are holding cinode->lock_sem that
         * protects locking operations of this inode.
         */
-       for (i = 0; i < count; i++) {
+       for (i = 0; i < flctx->flc_posix_cnt; i++) {
                lck = kmalloc(sizeof(struct lock_to_push), GFP_KERNEL);
                if (!lck) {
                        rc = -ENOMEM;
index 864f2460a0ad89bc1ec6510fd9124a07046b1f6f..bd578700342d47b0eb70d38768dbb2ff8969be0e 100644 (file)
@@ -681,18 +681,21 @@ static void locks_wake_up_blocks(struct file_lock *blocker)
 }
 
 static void
-locks_insert_lock_ctx(struct file_lock *fl, struct list_head *before)
+locks_insert_lock_ctx(struct file_lock *fl, int *counter,
+                     struct list_head *before)
 {
        fl->fl_nspid = get_pid(task_tgid(current));
        list_add_tail(&fl->fl_list, before);
+       ++*counter;
        locks_insert_global_locks(fl);
 }
 
 static void
-locks_unlink_lock_ctx(struct file_lock *fl)
+locks_unlink_lock_ctx(struct file_lock *fl, int *counter)
 {
        locks_delete_global_locks(fl);
        list_del_init(&fl->fl_list);
+       --*counter;
        if (fl->fl_nspid) {
                put_pid(fl->fl_nspid);
                fl->fl_nspid = NULL;
@@ -701,9 +704,10 @@ locks_unlink_lock_ctx(struct file_lock *fl)
 }
 
 static void
-locks_delete_lock_ctx(struct file_lock *fl, struct list_head *dispose)
+locks_delete_lock_ctx(struct file_lock *fl, int *counter,
+                     struct list_head *dispose)
 {
-       locks_unlink_lock_ctx(fl);
+       locks_unlink_lock_ctx(fl, counter);
        if (dispose)
                list_add(&fl->fl_list, dispose);
        else
@@ -891,7 +895,7 @@ static int flock_lock_file(struct file *filp, struct file_lock *request)
                if (request->fl_type == fl->fl_type)
                        goto out;
                found = true;
-               locks_delete_lock_ctx(fl, &dispose);
+               locks_delete_lock_ctx(fl, &ctx->flc_flock_cnt, &dispose);
                break;
        }
 
@@ -925,7 +929,7 @@ find_conflict:
        if (request->fl_flags & FL_ACCESS)
                goto out;
        locks_copy_lock(new_fl, request);
-       locks_insert_lock_ctx(new_fl, &ctx->flc_flock);
+       locks_insert_lock_ctx(new_fl, &ctx->flc_flock_cnt, &ctx->flc_flock);
        new_fl = NULL;
        error = 0;
 
@@ -1042,7 +1046,8 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str
                        else
                                request->fl_end = fl->fl_end;
                        if (added) {
-                               locks_delete_lock_ctx(fl, &dispose);
+                               locks_delete_lock_ctx(fl, &ctx->flc_posix_cnt,
+                                                       &dispose);
                                continue;
                        }
                        request = fl;
@@ -1071,7 +1076,8 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str
                                 * one (This may happen several times).
                                 */
                                if (added) {
-                                       locks_delete_lock_ctx(fl, &dispose);
+                                       locks_delete_lock_ctx(fl,
+                                               &ctx->flc_posix_cnt, &dispose);
                                        continue;
                                }
                                /*
@@ -1087,8 +1093,10 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str
                                locks_copy_lock(new_fl, request);
                                request = new_fl;
                                new_fl = NULL;
-                               locks_insert_lock_ctx(request, &fl->fl_list);
-                               locks_delete_lock_ctx(fl, &dispose);
+                               locks_insert_lock_ctx(request,
+                                       &ctx->flc_posix_cnt, &fl->fl_list);
+                               locks_delete_lock_ctx(fl,
+                                       &ctx->flc_posix_cnt, &dispose);
                                added = true;
                        }
                }
@@ -1116,7 +1124,8 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str
                        goto out;
                }
                locks_copy_lock(new_fl, request);
-               locks_insert_lock_ctx(new_fl, &fl->fl_list);
+               locks_insert_lock_ctx(new_fl, &ctx->flc_posix_cnt,
+                                       &fl->fl_list);
                new_fl = NULL;
        }
        if (right) {
@@ -1127,7 +1136,8 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str
                        left = new_fl2;
                        new_fl2 = NULL;
                        locks_copy_lock(left, right);
-                       locks_insert_lock_ctx(left, &fl->fl_list);
+                       locks_insert_lock_ctx(left, &ctx->flc_posix_cnt,
+                                               &fl->fl_list);
                }
                right->fl_start = request->fl_end + 1;
                locks_wake_up_blocks(right);
@@ -1311,6 +1321,7 @@ static void lease_clear_pending(struct file_lock *fl, int arg)
 /* We already had a lease on this file; just change its type */
 int lease_modify(struct file_lock *fl, int arg, struct list_head *dispose)
 {
+       struct file_lock_context *flctx;
        int error = assign_type(fl, arg);
 
        if (error)
@@ -1320,6 +1331,7 @@ int lease_modify(struct file_lock *fl, int arg, struct list_head *dispose)
        if (arg == F_UNLCK) {
                struct file *filp = fl->fl_file;
 
+               flctx = file_inode(filp)->i_flctx;
                f_delown(filp);
                filp->f_owner.signum = 0;
                fasync_helper(0, fl->fl_file, 0, &fl->fl_fasync);
@@ -1327,7 +1339,7 @@ int lease_modify(struct file_lock *fl, int arg, struct list_head *dispose)
                        printk(KERN_ERR "locks_delete_lock: fasync == %p\n", fl->fl_fasync);
                        fl->fl_fasync = NULL;
                }
-               locks_delete_lock_ctx(fl, dispose);
+               locks_delete_lock_ctx(fl, &flctx->flc_lease_cnt, dispose);
        }
        return 0;
 }
@@ -1442,7 +1454,8 @@ int __break_lease(struct inode *inode, unsigned int mode, unsigned int type)
                        fl->fl_downgrade_time = break_time;
                }
                if (fl->fl_lmops->lm_break(fl))
-                       locks_delete_lock_ctx(fl, &dispose);
+                       locks_delete_lock_ctx(fl, &ctx->flc_lease_cnt,
+                                               &dispose);
        }
 
        if (list_empty(&ctx->flc_lease))
@@ -1678,7 +1691,7 @@ generic_add_lease(struct file *filp, long arg, struct file_lock **flp, void **pr
        if (!leases_enable)
                goto out;
 
-       locks_insert_lock_ctx(lease, &ctx->flc_lease);
+       locks_insert_lock_ctx(lease, &ctx->flc_lease_cnt, &ctx->flc_lease);
        /*
         * The check in break_lease() is lockless. It's possible for another
         * open to race in after we did the earlier check for a conflicting
@@ -1691,7 +1704,7 @@ generic_add_lease(struct file *filp, long arg, struct file_lock **flp, void **pr
        smp_mb();
        error = check_conflicting_open(dentry, arg);
        if (error) {
-               locks_unlink_lock_ctx(lease);
+               locks_unlink_lock_ctx(lease, &ctx->flc_lease_cnt);
                goto out;
        }
 
index 94e706a0a4083e7d44b11328de60a883b8f6a7cc..f87cb2f03103373be88fee94f4e69d17bfbdf8d3 100644 (file)
@@ -972,6 +972,9 @@ struct file_lock_context {
        struct list_head        flc_flock;
        struct list_head        flc_posix;
        struct list_head        flc_lease;
+       int                     flc_flock_cnt;
+       int                     flc_posix_cnt;
+       int                     flc_lease_cnt;
 };
 
 /* The following constant reflects the upper bound of the file/locking space */