brlocks/lglocks: cleanups

lglocks and brlocks are currently generated with some complicated macros
in lglock.h.  But there's no reason to not just use common utility
functions and put all the data into a common data structure.

Since there are at least two users it makes sense to share this code in a
library.  This is also easier maintainable than a macro forest.

This will also make it later possible to dynamically allocate lglocks and
also use them in modules (this would both still need some additional, but
now straightforward, code)

In general the users now look more like normal function calls with
pointers, not magic macros.

The patch is rather large because I move over all users in one go to keep
it bisectable.  This impacts the VFS somewhat in terms of lines changed.
But no actual behaviour change.

[akpm@linux-foundation.org: checkpatch fixes]
[levinsasha928@gmail.com: fix dup_mnt_ns()]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/fs/dcache.c b/fs/dcache.c
index b60ddc41d78385d168e67e98adc6020fedc1cfeb..58a6ecfbb06268483c27215376de6046b19785e8 100644 (file)
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -2489,7 +2489,7 @@ static int prepend_path(const struct path *path,
        bool slash = false;
        int error = 0;
 
-       br_read_lock(vfsmount_lock);
+       br_read_lock(&vfsmount_lock);
        while (dentry != root->dentry || vfsmnt != root->mnt) {
                struct dentry * parent;
 
@@ -2520,7 +2520,7 @@ static int prepend_path(const struct path *path,
                error = prepend(buffer, buflen, "/", 1);
 
 out:
-       br_read_unlock(vfsmount_lock);
+       br_read_unlock(&vfsmount_lock);
        return error;
 
 global_root:

diff --git a/fs/file_table.c b/fs/file_table.c
index 70f2a0fd6aec62b28724d46e356dc0ff871f88b8..a305d9e2d1b2aac05dcd456bdd23885652272439 100644 (file)
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -34,7 +34,6 @@ struct files_stat_struct files_stat = {
        .max_files = NR_FILE
 };
 
-DECLARE_LGLOCK(files_lglock);
 DEFINE_LGLOCK(files_lglock);
 
 /* SLAB cache for file structures */
@@ -421,9 +420,9 @@ static inline void __file_sb_list_add(struct file *file, struct super_block *sb)
  */
 void file_sb_list_add(struct file *file, struct super_block *sb)
 {
-       lg_local_lock(files_lglock);
+       lg_local_lock(&files_lglock);
        __file_sb_list_add(file, sb);
-       lg_local_unlock(files_lglock);
+       lg_local_unlock(&files_lglock);
 }
 
 /**
@@ -436,9 +435,9 @@ void file_sb_list_add(struct file *file, struct super_block *sb)
 void file_sb_list_del(struct file *file)
 {
        if (!list_empty(&file->f_u.fu_list)) {
-               lg_local_lock_cpu(files_lglock, file_list_cpu(file));
+               lg_local_lock_cpu(&files_lglock, file_list_cpu(file));
                list_del_init(&file->f_u.fu_list);
-               lg_local_unlock_cpu(files_lglock, file_list_cpu(file));
+               lg_local_unlock_cpu(&files_lglock, file_list_cpu(file));
        }
 }
 
@@ -485,7 +484,7 @@ void mark_files_ro(struct super_block *sb)
        struct file *f;
 
 retry:
-       lg_global_lock(files_lglock);
+       lg_global_lock(&files_lglock);
        do_file_list_for_each_entry(sb, f) {
                struct vfsmount *mnt;
                if (!S_ISREG(f->f_path.dentry->d_inode->i_mode))
@@ -502,12 +501,12 @@ retry:
                file_release_write(f);
                mnt = mntget(f->f_path.mnt);
                /* This can sleep, so we can't hold the spinlock. */
-               lg_global_unlock(files_lglock);
+               lg_global_unlock(&files_lglock);
                mnt_drop_write(mnt);
                mntput(mnt);
                goto retry;
        } while_file_list_for_each_entry;
-       lg_global_unlock(files_lglock);
+       lg_global_unlock(&files_lglock);
 }
 
 void __init files_init(unsigned long mempages)
@@ -525,6 +524,6 @@ void __init files_init(unsigned long mempages)
        n = (mempages * (PAGE_SIZE / 1024)) / 10;
        files_stat.max_files = max_t(unsigned long, n, NR_FILE);
        files_defer_init();
-       lg_lock_init(files_lglock);
+       lg_lock_init(&files_lglock, "files_lglock");
        percpu_counter_init(&nr_files, 0);
 } 

diff --git a/fs/internal.h b/fs/internal.h
index 9962c59ba280b1c75d78adc55b8491733075a5e0..0765acf586ef1784c50ccd8a39902891facb62bc 100644 (file)
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -56,8 +56,7 @@ extern int sb_prepare_remount_readonly(struct super_block *);
 
 extern void __init mnt_init(void);
 
-DECLARE_BRLOCK(vfsmount_lock);
-
+extern struct lglock vfsmount_lock;
 
 /*
  * fs_struct.c

diff --git a/fs/namei.c b/fs/namei.c
index 1bb54dd130a462dbea599939719c0f44e23b2932..1cf23510f2d1389ad1997bfd6e0e442fe851a404 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -462,7 +462,7 @@ static int unlazy_walk(struct nameidata *nd, struct dentry *dentry)
        mntget(nd->path.mnt);
 
        rcu_read_unlock();
-       br_read_unlock(vfsmount_lock);
+       br_read_unlock(&vfsmount_lock);
        nd->flags &= ~LOOKUP_RCU;
        return 0;
 
@@ -520,14 +520,14 @@ static int complete_walk(struct nameidata *nd)
                if (unlikely(!__d_rcu_to_refcount(dentry, nd->seq))) {
                        spin_unlock(&dentry->d_lock);
                        rcu_read_unlock();
-                       br_read_unlock(vfsmount_lock);
+                       br_read_unlock(&vfsmount_lock);
                        return -ECHILD;
                }
                BUG_ON(nd->inode != dentry->d_inode);
                spin_unlock(&dentry->d_lock);
                mntget(nd->path.mnt);
                rcu_read_unlock();
-               br_read_unlock(vfsmount_lock);
+               br_read_unlock(&vfsmount_lock);
        }
 
        if (likely(!(nd->flags & LOOKUP_JUMPED)))
@@ -846,15 +846,15 @@ int follow_up(struct path *path)
        struct mount *parent;
        struct dentry *mountpoint;
 
-       br_read_lock(vfsmount_lock);
+       br_read_lock(&vfsmount_lock);
        parent = mnt->mnt_parent;
        if (&parent->mnt == path->mnt) {
-               br_read_unlock(vfsmount_lock);
+               br_read_unlock(&vfsmount_lock);
                return 0;
        }
        mntget(&parent->mnt);
        mountpoint = dget(mnt->mnt_mountpoint);
-       br_read_unlock(vfsmount_lock);
+       br_read_unlock(&vfsmount_lock);
        dput(path->dentry);
        path->dentry = mountpoint;
        mntput(path->mnt);
@@ -1112,7 +1112,7 @@ failed:
        if (!(nd->flags & LOOKUP_ROOT))
                nd->root.mnt = NULL;
        rcu_read_unlock();
-       br_read_unlock(vfsmount_lock);
+       br_read_unlock(&vfsmount_lock);
        return -ECHILD;
 }
 
@@ -1417,7 +1417,7 @@ static void terminate_walk(struct nameidata *nd)
                if (!(nd->flags & LOOKUP_ROOT))
                        nd->root.mnt = NULL;
                rcu_read_unlock();
-               br_read_unlock(vfsmount_lock);
+               br_read_unlock(&vfsmount_lock);
        }
 }
 
@@ -1770,7 +1770,7 @@ static int path_init(int dfd, const char *name, unsigned int flags,
                nd->path = nd->root;
                nd->inode = inode;
                if (flags & LOOKUP_RCU) {
-                       br_read_lock(vfsmount_lock);
+                       br_read_lock(&vfsmount_lock);
                        rcu_read_lock();
                        nd->seq = __read_seqcount_begin(&nd->path.dentry->d_seq);
                } else {
@@ -1783,7 +1783,7 @@ static int path_init(int dfd, const char *name, unsigned int flags,
 
        if (*name=='/') {
                if (flags & LOOKUP_RCU) {
-                       br_read_lock(vfsmount_lock);
+                       br_read_lock(&vfsmount_lock);
                        rcu_read_lock();
                        set_root_rcu(nd);
                } else {
@@ -1796,7 +1796,7 @@ static int path_init(int dfd, const char *name, unsigned int flags,
                        struct fs_struct *fs = current->fs;
                        unsigned seq;
 
-                       br_read_lock(vfsmount_lock);
+                       br_read_lock(&vfsmount_lock);
                        rcu_read_lock();
 
                        do {
@@ -1832,7 +1832,7 @@ static int path_init(int dfd, const char *name, unsigned int flags,
                        if (fput_needed)
                                *fp = file;
                        nd->seq = __read_seqcount_begin(&nd->path.dentry->d_seq);
-                       br_read_lock(vfsmount_lock);
+                       br_read_lock(&vfsmount_lock);
                        rcu_read_lock();
                } else {
                        path_get(&file->f_path);

diff --git a/fs/namespace.c b/fs/namespace.c
index e6081996c9a2f9d26525740545445630c4737583..224aff1c0dfda0d964e8d5248b658c8c8c334af1 100644 (file)
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -397,7 +397,7 @@ static int mnt_make_readonly(struct mount *mnt)
 {
        int ret = 0;
 
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
        mnt->mnt.mnt_flags |= MNT_WRITE_HOLD;
        /*
         * After storing MNT_WRITE_HOLD, we'll read the counters. This store
@@ -431,15 +431,15 @@ static int mnt_make_readonly(struct mount *mnt)
         */
        smp_wmb();
        mnt->mnt.mnt_flags &= ~MNT_WRITE_HOLD;
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
        return ret;
 }
 
 static void __mnt_unmake_readonly(struct mount *mnt)
 {
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
        mnt->mnt.mnt_flags &= ~MNT_READONLY;
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
 }
 
 int sb_prepare_remount_readonly(struct super_block *sb)
@@ -451,7 +451,7 @@ int sb_prepare_remount_readonly(struct super_block *sb)
        if (atomic_long_read(&sb->s_remove_count))
                return -EBUSY;
 
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
        list_for_each_entry(mnt, &sb->s_mounts, mnt_instance) {
                if (!(mnt->mnt.mnt_flags & MNT_READONLY)) {
                        mnt->mnt.mnt_flags |= MNT_WRITE_HOLD;
@@ -473,7 +473,7 @@ int sb_prepare_remount_readonly(struct super_block *sb)
                if (mnt->mnt.mnt_flags & MNT_WRITE_HOLD)
                        mnt->mnt.mnt_flags &= ~MNT_WRITE_HOLD;
        }
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
 
        return err;
 }
@@ -522,14 +522,14 @@ struct vfsmount *lookup_mnt(struct path *path)
 {
        struct mount *child_mnt;
 
-       br_read_lock(vfsmount_lock);
+       br_read_lock(&vfsmount_lock);
        child_mnt = __lookup_mnt(path->mnt, path->dentry, 1);
        if (child_mnt) {
                mnt_add_count(child_mnt, 1);
-               br_read_unlock(vfsmount_lock);
+               br_read_unlock(&vfsmount_lock);
                return &child_mnt->mnt;
        } else {
-               br_read_unlock(vfsmount_lock);
+               br_read_unlock(&vfsmount_lock);
                return NULL;
        }
 }
@@ -714,9 +714,9 @@ vfs_kern_mount(struct file_system_type *type, int flags, const char *name, void
        mnt->mnt.mnt_sb = root->d_sb;
        mnt->mnt_mountpoint = mnt->mnt.mnt_root;
        mnt->mnt_parent = mnt;
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
        list_add_tail(&mnt->mnt_instance, &root->d_sb->s_mounts);
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
        return &mnt->mnt;
 }
 EXPORT_SYMBOL_GPL(vfs_kern_mount);
@@ -745,9 +745,9 @@ static struct mount *clone_mnt(struct mount *old, struct dentry *root,
                mnt->mnt.mnt_root = dget(root);
                mnt->mnt_mountpoint = mnt->mnt.mnt_root;
                mnt->mnt_parent = mnt;
-               br_write_lock(vfsmount_lock);
+               br_write_lock(&vfsmount_lock);
                list_add_tail(&mnt->mnt_instance, &sb->s_mounts);
-               br_write_unlock(vfsmount_lock);
+               br_write_unlock(&vfsmount_lock);
 
                if (flag & CL_SLAVE) {
                        list_add(&mnt->mnt_slave, &old->mnt_slave_list);
@@ -803,35 +803,36 @@ static void mntput_no_expire(struct mount *mnt)
 {
 put_again:
 #ifdef CONFIG_SMP
-       br_read_lock(vfsmount_lock);
+       br_read_lock(&vfsmount_lock);
        if (likely(atomic_read(&mnt->mnt_longterm))) {
                mnt_add_count(mnt, -1);
-               br_read_unlock(vfsmount_lock);
+               br_read_unlock(&vfsmount_lock);
                return;
        }
-       br_read_unlock(vfsmount_lock);
+       br_read_unlock(&vfsmount_lock);
 
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
        mnt_add_count(mnt, -1);
        if (mnt_get_count(mnt)) {
-               br_write_unlock(vfsmount_lock);
+               br_write_unlock(&vfsmount_lock);
                return;
        }
 #else
        mnt_add_count(mnt, -1);
        if (likely(mnt_get_count(mnt)))
                return;
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
 #endif
        if (unlikely(mnt->mnt_pinned)) {
                mnt_add_count(mnt, mnt->mnt_pinned + 1);
                mnt->mnt_pinned = 0;
-               br_write_unlock(vfsmount_lock);
+               br_write_unlock(&vfsmount_lock);
                acct_auto_close_mnt(&mnt->mnt);
                goto put_again;
        }
+
        list_del(&mnt->mnt_instance);
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
        mntfree(mnt);
 }
 
@@ -857,21 +858,21 @@ EXPORT_SYMBOL(mntget);
 
 void mnt_pin(struct vfsmount *mnt)
 {
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
        real_mount(mnt)->mnt_pinned++;
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
 }
 EXPORT_SYMBOL(mnt_pin);
 
 void mnt_unpin(struct vfsmount *m)
 {
        struct mount *mnt = real_mount(m);
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
        if (mnt->mnt_pinned) {
                mnt_add_count(mnt, 1);
                mnt->mnt_pinned--;
        }
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
 }
 EXPORT_SYMBOL(mnt_unpin);
 
@@ -988,12 +989,12 @@ int may_umount_tree(struct vfsmount *m)
        BUG_ON(!m);
 
        /* write lock needed for mnt_get_count */
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
        for (p = mnt; p; p = next_mnt(p, mnt)) {
                actual_refs += mnt_get_count(p);
                minimum_refs += 2;
        }
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
 
        if (actual_refs > minimum_refs)
                return 0;
@@ -1020,10 +1021,10 @@ int may_umount(struct vfsmount *mnt)
 {
        int ret = 1;
        down_read(&namespace_sem);
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
        if (propagate_mount_busy(real_mount(mnt), 2))
                ret = 0;
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
        up_read(&namespace_sem);
        return ret;
 }
@@ -1040,13 +1041,13 @@ void release_mounts(struct list_head *head)
                        struct dentry *dentry;
                        struct mount *m;
 
-                       br_write_lock(vfsmount_lock);
+                       br_write_lock(&vfsmount_lock);
                        dentry = mnt->mnt_mountpoint;
                        m = mnt->mnt_parent;
                        mnt->mnt_mountpoint = mnt->mnt.mnt_root;
                        mnt->mnt_parent = mnt;
                        m->mnt_ghosts--;
-                       br_write_unlock(vfsmount_lock);
+                       br_write_unlock(&vfsmount_lock);
                        dput(dentry);
                        mntput(&m->mnt);
                }
@@ -1112,12 +1113,12 @@ static int do_umount(struct mount *mnt, int flags)
                 * probably don't strictly need the lock here if we examined
                 * all race cases, but it's a slowpath.
                 */
-               br_write_lock(vfsmount_lock);
+               br_write_lock(&vfsmount_lock);
                if (mnt_get_count(mnt) != 2) {
-                       br_write_unlock(vfsmount_lock);
+                       br_write_unlock(&vfsmount_lock);
                        return -EBUSY;
                }
-               br_write_unlock(vfsmount_lock);
+               br_write_unlock(&vfsmount_lock);
 
                if (!xchg(&mnt->mnt_expiry_mark, 1))
                        return -EAGAIN;
@@ -1159,7 +1160,7 @@ static int do_umount(struct mount *mnt, int flags)
        }
 
        down_write(&namespace_sem);
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
        event++;
 
        if (!(flags & MNT_DETACH))
@@ -1171,7 +1172,7 @@ static int do_umount(struct mount *mnt, int flags)
                        umount_tree(mnt, 1, &umount_list);
                retval = 0;
        }
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
        up_write(&namespace_sem);
        release_mounts(&umount_list);
        return retval;
@@ -1286,19 +1287,19 @@ struct mount *copy_tree(struct mount *mnt, struct dentry *dentry,
                        q = clone_mnt(p, p->mnt.mnt_root, flag);
                        if (!q)
                                goto Enomem;
-                       br_write_lock(vfsmount_lock);
+                       br_write_lock(&vfsmount_lock);
                        list_add_tail(&q->mnt_list, &res->mnt_list);
                        attach_mnt(q, &path);
-                       br_write_unlock(vfsmount_lock);
+                       br_write_unlock(&vfsmount_lock);
                }
        }
        return res;
 Enomem:
        if (res) {
                LIST_HEAD(umount_list);
-               br_write_lock(vfsmount_lock);
+               br_write_lock(&vfsmount_lock);
                umount_tree(res, 0, &umount_list);
-               br_write_unlock(vfsmount_lock);
+               br_write_unlock(&vfsmount_lock);
                release_mounts(&umount_list);
        }
        return NULL;
@@ -1318,9 +1319,9 @@ void drop_collected_mounts(struct vfsmount *mnt)
 {
        LIST_HEAD(umount_list);
        down_write(&namespace_sem);
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
        umount_tree(real_mount(mnt), 0, &umount_list);
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
        up_write(&namespace_sem);
        release_mounts(&umount_list);
 }
@@ -1448,7 +1449,7 @@ static int attach_recursive_mnt(struct mount *source_mnt,
        if (err)
                goto out_cleanup_ids;
 
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
 
        if (IS_MNT_SHARED(dest_mnt)) {
                for (p = source_mnt; p; p = next_mnt(p, source_mnt))
@@ -1467,7 +1468,7 @@ static int attach_recursive_mnt(struct mount *source_mnt,
                list_del_init(&child->mnt_hash);
                commit_tree(child);
        }
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
 
        return 0;
 
@@ -1565,10 +1566,10 @@ static int do_change_type(struct path *path, int flag)
                        goto out_unlock;
        }
 
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
        for (m = mnt; m; m = (recurse ? next_mnt(m, mnt) : NULL))
                change_mnt_propagation(m, type);
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
 
  out_unlock:
        up_write(&namespace_sem);
@@ -1617,9 +1618,9 @@ static int do_loopback(struct path *path, char *old_name,
 
        err = graft_tree(mnt, path);
        if (err) {
-               br_write_lock(vfsmount_lock);
+               br_write_lock(&vfsmount_lock);
                umount_tree(mnt, 0, &umount_list);
-               br_write_unlock(vfsmount_lock);
+               br_write_unlock(&vfsmount_lock);
        }
 out2:
        unlock_mount(path);
@@ -1677,16 +1678,16 @@ static int do_remount(struct path *path, int flags, int mnt_flags,
        else
                err = do_remount_sb(sb, flags, data, 0);
        if (!err) {
-               br_write_lock(vfsmount_lock);
+               br_write_lock(&vfsmount_lock);
                mnt_flags |= mnt->mnt.mnt_flags & MNT_PROPAGATION_MASK;
                mnt->mnt.mnt_flags = mnt_flags;
-               br_write_unlock(vfsmount_lock);
+               br_write_unlock(&vfsmount_lock);
        }
        up_write(&sb->s_umount);
        if (!err) {
-               br_write_lock(vfsmount_lock);
+               br_write_lock(&vfsmount_lock);
                touch_mnt_namespace(mnt->mnt_ns);
-               br_write_unlock(vfsmount_lock);
+               br_write_unlock(&vfsmount_lock);
        }
        return err;
 }
@@ -1893,9 +1894,9 @@ fail:
        /* remove m from any expiration list it may be on */
        if (!list_empty(&mnt->mnt_expire)) {
                down_write(&namespace_sem);
-               br_write_lock(vfsmount_lock);
+               br_write_lock(&vfsmount_lock);
                list_del_init(&mnt->mnt_expire);
-               br_write_unlock(vfsmount_lock);
+               br_write_unlock(&vfsmount_lock);
                up_write(&namespace_sem);
        }
        mntput(m);
@@ -1911,11 +1912,11 @@ fail:
 void mnt_set_expiry(struct vfsmount *mnt, struct list_head *expiry_list)
 {
        down_write(&namespace_sem);
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
 
        list_add_tail(&real_mount(mnt)->mnt_expire, expiry_list);
 
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
        up_write(&namespace_sem);
 }
 EXPORT_SYMBOL(mnt_set_expiry);
@@ -1935,7 +1936,7 @@ void mark_mounts_for_expiry(struct list_head *mounts)
                return;
 
        down_write(&namespace_sem);
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
 
        /* extract from the expiration list every vfsmount that matches the
         * following criteria:
@@ -1954,7 +1955,7 @@ void mark_mounts_for_expiry(struct list_head *mounts)
                touch_mnt_namespace(mnt->mnt_ns);
                umount_tree(mnt, 1, &umounts);
        }
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
        up_write(&namespace_sem);
 
        release_mounts(&umounts);
@@ -2218,9 +2219,9 @@ void mnt_make_shortterm(struct vfsmount *m)
        struct mount *mnt = real_mount(m);
        if (atomic_add_unless(&mnt->mnt_longterm, -1, 1))
                return;
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
        atomic_dec(&mnt->mnt_longterm);
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
 #endif
 }
 
@@ -2250,9 +2251,9 @@ static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns,
                return ERR_PTR(-ENOMEM);
        }
        new_ns->root = new;
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
        list_add_tail(&new_ns->list, &new->mnt_list);
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
 
        /*
         * Second pass: switch the tsk->fs->* elements and mark new vfsmounts
@@ -2416,9 +2417,9 @@ bool is_path_reachable(struct mount *mnt, struct dentry *dentry,
 int path_is_under(struct path *path1, struct path *path2)
 {
        int res;
-       br_read_lock(vfsmount_lock);
+       br_read_lock(&vfsmount_lock);
        res = is_path_reachable(real_mount(path1->mnt), path1->dentry, path2);
-       br_read_unlock(vfsmount_lock);
+       br_read_unlock(&vfsmount_lock);
        return res;
 }
 EXPORT_SYMBOL(path_is_under);
@@ -2505,7 +2506,7 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root,
        /* make sure we can reach put_old from new_root */
        if (!is_path_reachable(real_mount(old.mnt), old.dentry, &new))
                goto out4;
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
        detach_mnt(new_mnt, &parent_path);
        detach_mnt(root_mnt, &root_parent);
        /* mount old root on put_old */
@@ -2513,7 +2514,7 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root,
        /* mount new_root on / */
        attach_mnt(new_mnt, &root_parent);
        touch_mnt_namespace(current->nsproxy->mnt_ns);
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
        chroot_fs_refs(&root, &new);
        error = 0;
 out4:
@@ -2576,7 +2577,7 @@ void __init mnt_init(void)
        for (u = 0; u < HASH_SIZE; u++)
                INIT_LIST_HEAD(&mount_hashtable[u]);
 
-       br_lock_init(vfsmount_lock);
+       br_lock_init(&vfsmount_lock);
 
        err = sysfs_init();
        if (err)
@@ -2596,9 +2597,9 @@ void put_mnt_ns(struct mnt_namespace *ns)
        if (!atomic_dec_and_test(&ns->count))
                return;
        down_write(&namespace_sem);
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
        umount_tree(ns->root, 0, &umount_list);
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
        up_write(&namespace_sem);
        release_mounts(&umount_list);
        kfree(ns);

diff --git a/fs/pnode.c b/fs/pnode.c
index ab5fa9e1a79ac8277ac1cb51db6a92e55ba2c935..bed378db075813350362c39f423d1b4335240bfa 100644 (file)
--- a/fs/pnode.c
+++ b/fs/pnode.c
@@ -257,12 +257,12 @@ int propagate_mnt(struct mount *dest_mnt, struct dentry *dest_dentry,
                prev_src_mnt  = child;
        }
 out:
-       br_write_lock(vfsmount_lock);
+       br_write_lock(&vfsmount_lock);
        while (!list_empty(&tmp_list)) {
                child = list_first_entry(&tmp_list, struct mount, mnt_hash);
                umount_tree(child, 0, &umount_list);
        }
-       br_write_unlock(vfsmount_lock);
+       br_write_unlock(&vfsmount_lock);
        release_mounts(&umount_list);
        return ret;
 }

diff --git a/fs/proc_namespace.c b/fs/proc_namespace.c
index 12412852d88a94d574bacebb5e64200f202db852..5e289a7cbad17d8547458f1d8b2526f2e85e5cb9 100644 (file)
--- a/fs/proc_namespace.c
+++ b/fs/proc_namespace.c
@@ -23,12 +23,12 @@ static unsigned mounts_poll(struct file *file, poll_table *wait)
 
        poll_wait(file, &p->ns->poll, wait);
 
-       br_read_lock(vfsmount_lock);
+       br_read_lock(&vfsmount_lock);
        if (p->m.poll_event != ns->event) {
                p->m.poll_event = ns->event;
                res |= POLLERR | POLLPRI;
        }
-       br_read_unlock(vfsmount_lock);
+       br_read_unlock(&vfsmount_lock);
 
        return res;
 }

diff --git a/include/linux/lglock.h b/include/linux/lglock.h
index 87f402ccec55567330943ab774ffb12ae21c7da8..51520561c9e9c2ee13b654cd05d7f87d6a137655 100644 (file)
--- a/include/linux/lglock.h
+++ b/include/linux/lglock.h
@@ -23,28 +23,17 @@
 #include <linux/lockdep.h>
 #include <linux/percpu.h>
 #include <linux/cpu.h>
+#include <linux/notifier.h>
 
 /* can make br locks by using local lock for read side, global lock for write */
-#define br_lock_init(name)     name##_lock_init()
-#define br_read_lock(name)     name##_local_lock()
-#define br_read_unlock(name)   name##_local_unlock()
-#define br_write_lock(name)    name##_global_lock_online()
-#define br_write_unlock(name)  name##_global_unlock_online()
+#define br_lock_init(name)     lg_lock_init(name, #name)
+#define br_read_lock(name)     lg_local_lock(name)
+#define br_read_unlock(name)   lg_local_unlock(name)
+#define br_write_lock(name)    lg_global_lock_online(name)
+#define br_write_unlock(name)  lg_global_unlock_online(name)
 
-#define DECLARE_BRLOCK(name)   DECLARE_LGLOCK(name)
 #define DEFINE_BRLOCK(name)    DEFINE_LGLOCK(name)
 
-
-#define lg_lock_init(name)     name##_lock_init()
-#define lg_local_lock(name)    name##_local_lock()
-#define lg_local_unlock(name)  name##_local_unlock()
-#define lg_local_lock_cpu(name, cpu)   name##_local_lock_cpu(cpu)
-#define lg_local_unlock_cpu(name, cpu) name##_local_unlock_cpu(cpu)
-#define lg_global_lock(name)   name##_global_lock()
-#define lg_global_unlock(name) name##_global_unlock()
-#define lg_global_lock_online(name) name##_global_lock_online()
-#define lg_global_unlock_online(name) name##_global_unlock_online()
-
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 #define LOCKDEP_INIT_MAP lockdep_init_map
 
@@ -59,142 +48,34 @@
 #define DEFINE_LGLOCK_LOCKDEP(name)
 #endif
 
+struct lglock {
+       arch_spinlock_t __percpu *lock;
+       cpumask_t cpus; /* XXX need to put on separate cacheline? */
+       spinlock_t cpu_lock;
+       struct notifier_block cpu_notifier;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+       struct lock_class_key lock_key;
+       struct lockdep_map    lock_dep_map;
+#endif
+};
+
+#define DEFINE_LGLOCK(name) \
+       DEFINE_PER_CPU(arch_spinlock_t, name ## _lock) = __ARCH_SPIN_LOCK_UNLOCKED; \
+       struct lglock name = { .lock = &name ## _lock,                          \
+                              .cpu_lock = __SPIN_LOCK_UNLOCKED(cpu_lock),      \
+                              .cpu_notifier.notifier_call = lg_cpu_callback }
+
+/* Only valid for statics */
+void lg_lock_init(struct lglock *lg, char *name);
+void lg_local_lock(struct lglock *lg);
+void lg_local_unlock(struct lglock *lg);
+void lg_local_lock_cpu(struct lglock *lg, int cpu);
+void lg_local_unlock_cpu(struct lglock *lg, int cpu);
+void lg_global_lock_online(struct lglock *lg);
+void lg_global_unlock_online(struct lglock *lg);
+void lg_global_lock(struct lglock *lg);
+void lg_global_unlock(struct lglock *lg);
 
-#define DECLARE_LGLOCK(name)                                           \
- extern void name##_lock_init(void);                                   \
- extern void name##_local_lock(void);                                  \
- extern void name##_local_unlock(void);                                        \
- extern void name##_local_lock_cpu(int cpu);                           \
- extern void name##_local_unlock_cpu(int cpu);                         \
- extern void name##_global_lock(void);                                 \
- extern void name##_global_unlock(void);                               \
- extern void name##_global_lock_online(void);                          \
- extern void name##_global_unlock_online(void);                                \
+int lg_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu);
 
-#define DEFINE_LGLOCK(name)                                            \
-                                                                       \
- DEFINE_SPINLOCK(name##_cpu_lock);                                     \
- cpumask_t name##_cpus __read_mostly;                                  \
- DEFINE_PER_CPU(arch_spinlock_t, name##_lock);                         \
- DEFINE_LGLOCK_LOCKDEP(name);                                          \
-                                                                       \
- static int                                                            \
- name##_lg_cpu_callback(struct notifier_block *nb,                     \
-                               unsigned long action, void *hcpu)       \
- {                                                                     \
-       switch (action & ~CPU_TASKS_FROZEN) {                           \
-       case CPU_UP_PREPARE:                                            \
-               spin_lock(&name##_cpu_lock);                            \
-               cpu_set((unsigned long)hcpu, name##_cpus);              \
-               spin_unlock(&name##_cpu_lock);                          \
-               break;                                                  \
-       case CPU_UP_CANCELED: case CPU_DEAD:                            \
-               spin_lock(&name##_cpu_lock);                            \
-               cpu_clear((unsigned long)hcpu, name##_cpus);            \
-               spin_unlock(&name##_cpu_lock);                          \
-       }                                                               \
-       return NOTIFY_OK;                                               \
- }                                                                     \
- static struct notifier_block name##_lg_cpu_notifier = {               \
-       .notifier_call = name##_lg_cpu_callback,                        \
- };                                                                    \
- void name##_lock_init(void) {                                         \
-       int i;                                                          \
-       LOCKDEP_INIT_MAP(&name##_lock_dep_map, #name, &name##_lock_key, 0); \
-       for_each_possible_cpu(i) {                                      \
-               arch_spinlock_t *lock;                                  \
-               lock = &per_cpu(name##_lock, i);                        \
-               *lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;     \
-       }                                                               \
-       register_hotcpu_notifier(&name##_lg_cpu_notifier);              \
-       get_online_cpus();                                              \
-       for_each_online_cpu(i)                                          \
-               cpu_set(i, name##_cpus);                                \
-       put_online_cpus();                                              \
- }                                                                     \
- EXPORT_SYMBOL(name##_lock_init);                                      \
-                                                                       \
- void name##_local_lock(void) {                                                \
-       arch_spinlock_t *lock;                                          \
-       preempt_disable();                                              \
-       rwlock_acquire_read(&name##_lock_dep_map, 0, 0, _THIS_IP_);     \
-       lock = &__get_cpu_var(name##_lock);                             \
-       arch_spin_lock(lock);                                           \
- }                                                                     \
- EXPORT_SYMBOL(name##_local_lock);                                     \
-                                                                       \
- void name##_local_unlock(void) {                                      \
-       arch_spinlock_t *lock;                                          \
-       rwlock_release(&name##_lock_dep_map, 1, _THIS_IP_);             \
-       lock = &__get_cpu_var(name##_lock);                             \
-       arch_spin_unlock(lock);                                         \
-       preempt_enable();                                               \
- }                                                                     \
- EXPORT_SYMBOL(name##_local_unlock);                                   \
-                                                                       \
- void name##_local_lock_cpu(int cpu) {                                 \
-       arch_spinlock_t *lock;                                          \
-       preempt_disable();                                              \
-       rwlock_acquire_read(&name##_lock_dep_map, 0, 0, _THIS_IP_);     \
-       lock = &per_cpu(name##_lock, cpu);                              \
-       arch_spin_lock(lock);                                           \
- }                                                                     \
- EXPORT_SYMBOL(name##_local_lock_cpu);                                 \
-                                                                       \
- void name##_local_unlock_cpu(int cpu) {                               \
-       arch_spinlock_t *lock;                                          \
-       rwlock_release(&name##_lock_dep_map, 1, _THIS_IP_);             \
-       lock = &per_cpu(name##_lock, cpu);                              \
-       arch_spin_unlock(lock);                                         \
-       preempt_enable();                                               \
- }                                                                     \
- EXPORT_SYMBOL(name##_local_unlock_cpu);                               \
-                                                                       \
- void name##_global_lock_online(void) {                                        \
-       int i;                                                          \
-       spin_lock(&name##_cpu_lock);                                    \
-       rwlock_acquire(&name##_lock_dep_map, 0, 0, _RET_IP_);           \
-       for_each_cpu(i, &name##_cpus) {                                 \
-               arch_spinlock_t *lock;                                  \
-               lock = &per_cpu(name##_lock, i);                        \
-               arch_spin_lock(lock);                                   \
-       }                                                               \
- }                                                                     \
- EXPORT_SYMBOL(name##_global_lock_online);                             \
-                                                                       \
- void name##_global_unlock_online(void) {                              \
-       int i;                                                          \
-       rwlock_release(&name##_lock_dep_map, 1, _RET_IP_);              \
-       for_each_cpu(i, &name##_cpus) {                                 \
-               arch_spinlock_t *lock;                                  \
-               lock = &per_cpu(name##_lock, i);                        \
-               arch_spin_unlock(lock);                                 \
-       }                                                               \
-       spin_unlock(&name##_cpu_lock);                                  \
- }                                                                     \
- EXPORT_SYMBOL(name##_global_unlock_online);                           \
-                                                                       \
- void name##_global_lock(void) {                                       \
-       int i;                                                          \
-       preempt_disable();                                              \
-       rwlock_acquire(&name##_lock_dep_map, 0, 0, _RET_IP_);           \
-       for_each_possible_cpu(i) {                                      \
-               arch_spinlock_t *lock;                                  \
-               lock = &per_cpu(name##_lock, i);                        \
-               arch_spin_lock(lock);                                   \
-       }                                                               \
- }                                                                     \
- EXPORT_SYMBOL(name##_global_lock);                                    \
-                                                                       \
- void name##_global_unlock(void) {                                     \
-       int i;                                                          \
-       rwlock_release(&name##_lock_dep_map, 1, _RET_IP_);              \
-       for_each_possible_cpu(i) {                                      \
-               arch_spinlock_t *lock;                                  \
-               lock = &per_cpu(name##_lock, i);                        \
-               arch_spin_unlock(lock);                                 \
-       }                                                               \
-       preempt_enable();                                               \
- }                                                                     \
- EXPORT_SYMBOL(name##_global_unlock);
 #endif

diff --git a/kernel/Makefile b/kernel/Makefile
index cb41b9547c9f082b4978ef425771b6b0c38c57a6..ace94dd413533d5b0f64610fcc6caf58aa647e86 100644 (file)
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -10,7 +10,7 @@ obj-y     = fork.o exec_domain.o panic.o printk.o \
            kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \
            hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
            notifier.o ksysfs.o cred.o \
-           async.o range.o groups.o
+           async.o range.o groups.o lglock.o
 
 ifdef CONFIG_FUNCTION_TRACER
 # Do not trace debug files and internal ftrace files

diff --git a/kernel/lglock.c b/kernel/lglock.c
new file mode 100644 (file)
index 0000000..c6e6f09
--- /dev/null
+++ b/kernel/lglock.c
@@ -0,0 +1,136 @@
+/* See include/linux/lglock.h for description */
+#include <linux/module.h>
+#include <linux/lglock.h>
+#include <linux/cpu.h>
+#include <linux/string.h>
+
+/* Note there is no uninit, so lglocks cannot be defined in
+ * modules (but it's fine to use them from there)
+ * Could be added though, just undo lg_lock_init
+ */
+
+void lg_lock_init(struct lglock *lg, char *name)
+{
+       int i;
+
+       LOCKDEP_INIT_MAP(&lg->lock_dep_map, name, &lg->lock_key, 0);
+
+       register_hotcpu_notifier(&lg->cpu_notifier);
+       get_online_cpus();
+       for_each_online_cpu (i)
+               cpu_set(i, lg->cpus);
+       put_online_cpus();
+}
+EXPORT_SYMBOL(lg_lock_init);
+
+void lg_local_lock(struct lglock *lg)
+{
+       arch_spinlock_t *lock;
+       preempt_disable();
+       rwlock_acquire_read(&lg->lock_dep_map, 0, 0, _RET_IP_);
+       lock = this_cpu_ptr(lg->lock);
+       arch_spin_lock(lock);
+}
+EXPORT_SYMBOL(lg_local_lock);
+
+void lg_local_unlock(struct lglock *lg)
+{
+       arch_spinlock_t *lock;
+       rwlock_release(&lg->lock_dep_map, 1, _RET_IP_);
+       lock = this_cpu_ptr(lg->lock);
+       arch_spin_unlock(lock);
+       preempt_enable();
+}
+EXPORT_SYMBOL(lg_local_unlock);
+
+void lg_local_lock_cpu(struct lglock *lg, int cpu)
+{
+       arch_spinlock_t *lock;
+       preempt_disable();
+       rwlock_acquire_read(&lg->lock_dep_map, 0, 0, _RET_IP_);
+       lock = per_cpu_ptr(lg->lock, cpu);
+       arch_spin_lock(lock);
+}
+EXPORT_SYMBOL(lg_local_lock_cpu);
+
+void lg_local_unlock_cpu(struct lglock *lg, int cpu)
+{
+       arch_spinlock_t *lock;
+       rwlock_release(&lg->lock_dep_map, 1, _RET_IP_);
+       lock = per_cpu_ptr(lg->lock, cpu);
+       arch_spin_unlock(lock);
+       preempt_enable();
+}
+EXPORT_SYMBOL(lg_local_unlock_cpu);
+
+void lg_global_lock_online(struct lglock *lg)
+{
+       int i;
+       spin_lock(&lg->cpu_lock);
+       rwlock_acquire(&lg->lock_dep_map, 0, 0, _RET_IP_);
+       for_each_cpu(i, &lg->cpus) {
+               arch_spinlock_t *lock;
+               lock = per_cpu_ptr(lg->lock, i);
+               arch_spin_lock(lock);
+       }
+}
+EXPORT_SYMBOL(lg_global_lock_online);
+
+void lg_global_unlock_online(struct lglock *lg)
+{
+       int i;
+       rwlock_release(&lg->lock_dep_map, 1, _RET_IP_);
+       for_each_cpu(i, &lg->cpus) {
+               arch_spinlock_t *lock;
+               lock = per_cpu_ptr(lg->lock, i);
+               arch_spin_unlock(lock);
+       }
+       spin_unlock(&lg->cpu_lock);
+}
+EXPORT_SYMBOL(lg_global_unlock_online);
+
+void lg_global_lock(struct lglock *lg)
+{
+       int i;
+       preempt_disable();
+       rwlock_acquire(&lg->lock_dep_map, 0, 0, _RET_IP_);
+       for_each_possible_cpu(i) {
+               arch_spinlock_t *lock;
+               lock = per_cpu_ptr(lg->lock, i);
+               arch_spin_lock(lock);
+       }
+}
+EXPORT_SYMBOL(lg_global_lock);
+
+void lg_global_unlock(struct lglock *lg)
+{
+       int i;
+       rwlock_release(&lg->lock_dep_map, 1, _RET_IP_);
+       for_each_possible_cpu(i) {
+               arch_spinlock_t *lock;
+               lock = per_cpu_ptr(lg->lock, i);
+               arch_spin_unlock(lock);
+       }
+       preempt_enable();
+}
+EXPORT_SYMBOL(lg_global_unlock);
+
+int lg_cpu_callback(struct notifier_block *nb,
+                              unsigned long action, void *hcpu)
+{
+       struct lglock *lglock = container_of(nb, struct lglock, cpu_notifier);
+       switch (action & ~CPU_TASKS_FROZEN) {
+       case CPU_UP_PREPARE:
+               spin_lock(&lglock->cpu_lock);
+               cpu_set((unsigned long)hcpu, lglock->cpus);
+               spin_unlock(&lglock->cpu_lock);
+               break;
+       case CPU_UP_CANCELED: case CPU_DEAD:
+               spin_lock(&lglock->cpu_lock);
+               cpu_clear((unsigned long)hcpu, lglock->cpus);
+               spin_unlock(&lglock->cpu_lock);
+       }
+       return NOTIFY_OK;
+}
+EXPORT_SYMBOL(lg_cpu_callback);
+