diff options
author | Arnd Bergmann <arnd@arndb.de> | 2006-10-04 17:26:15 +0200 |
---|---|---|
committer | Paul Mackerras <paulus@samba.org> | 2006-10-05 09:21:01 +1000 |
commit | 6263203ed6e9ff107129a1ebe613290b342a4465 (patch) | |
tree | dc7d68b783fed2b5ffcb8905c62086ebe078368b /arch/powerpc/platforms/cell/spufs/inode.c | |
parent | 9add11daeee2f6d69f6b86237f197824332a4a3b (diff) | |
download | op-kernel-dev-6263203ed6e9ff107129a1ebe613290b342a4465.zip op-kernel-dev-6263203ed6e9ff107129a1ebe613290b342a4465.tar.gz |
[POWERPC] spufs: Add infrastructure needed for gang scheduling
Add the concept of a gang to spufs as a new type of object.
So far, this has no impact whatsover on scheduling, but makes
it possible to add that later.
A new type of object in spufs is now a spu_gang. It is created
with the spu_create system call with the flags argument set
to SPU_CREATE_GANG (0x2). Inside of a spu_gang, it
is then possible to create spu_context objects, which until
now was only possible at the root of spufs.
There is a new member in struct spu_context pointing to
the spu_gang it belongs to, if any. The spu_gang maintains
a list of spu_context structures that are its children.
This information can then be used in the scheduler in the
future.
There is still a bug that needs to be resolved in this
basic infrastructure regarding the order in which objects
are removed. When the spu_gang file descriptor is closed
before the spu_context descriptors, we leak the dentry
and inode for the gang. Any ideas how to cleanly solve
this are appreciated.
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/platforms/cell/spufs/inode.c')
-rw-r--r-- | arch/powerpc/platforms/cell/spufs/inode.c | 225 |
1 files changed, 189 insertions, 36 deletions
diff --git a/arch/powerpc/platforms/cell/spufs/inode.c b/arch/powerpc/platforms/cell/spufs/inode.c index 8cc615f..427d00a 100644 --- a/arch/powerpc/platforms/cell/spufs/inode.c +++ b/arch/powerpc/platforms/cell/spufs/inode.c @@ -50,6 +50,10 @@ spufs_alloc_inode(struct super_block *sb) ei = kmem_cache_alloc(spufs_inode_cache, SLAB_KERNEL); if (!ei) return NULL; + + ei->i_gang = NULL; + ei->i_ctx = NULL; + return &ei->vfs_inode; } @@ -128,14 +132,19 @@ out: static void spufs_delete_inode(struct inode *inode) { - if (SPUFS_I(inode)->i_ctx) - put_spu_context(SPUFS_I(inode)->i_ctx); + struct spufs_inode_info *ei = SPUFS_I(inode); + + if (ei->i_ctx) + put_spu_context(ei->i_ctx); + if (ei->i_gang) + put_spu_gang(ei->i_gang); clear_inode(inode); } static void spufs_prune_dir(struct dentry *dir) { struct dentry *dentry, *tmp; + mutex_lock(&dir->d_inode->i_mutex); list_for_each_entry_safe(dentry, tmp, &dir->d_subdirs, d_u.d_child) { spin_lock(&dcache_lock); @@ -156,13 +165,13 @@ static void spufs_prune_dir(struct dentry *dir) mutex_unlock(&dir->d_inode->i_mutex); } -/* Caller must hold root->i_mutex */ -static int spufs_rmdir(struct inode *root, struct dentry *dir_dentry) +/* Caller must hold parent->i_mutex */ +static int spufs_rmdir(struct inode *parent, struct dentry *dir) { /* remove all entries */ - spufs_prune_dir(dir_dentry); + spufs_prune_dir(dir); - return simple_rmdir(root, dir_dentry); + return simple_rmdir(parent, dir); } static int spufs_fill_dir(struct dentry *dir, struct tree_descr *files, @@ -191,17 +200,17 @@ out: static int spufs_dir_close(struct inode *inode, struct file *file) { struct spu_context *ctx; - struct inode *dir; - struct dentry *dentry; + struct inode *parent; + struct dentry *dir; int ret; - dentry = file->f_dentry; - dir = dentry->d_parent->d_inode; - ctx = SPUFS_I(dentry->d_inode)->i_ctx; + dir = file->f_dentry; + parent = dir->d_parent->d_inode; + ctx = SPUFS_I(dir->d_inode)->i_ctx; - mutex_lock(&dir->i_mutex); - ret = spufs_rmdir(dir, dentry); - mutex_unlock(&dir->i_mutex); + mutex_lock(&parent->i_mutex); + ret = spufs_rmdir(parent, dir); + mutex_unlock(&parent->i_mutex); WARN_ON(ret); /* We have to give up the mm_struct */ @@ -240,7 +249,7 @@ spufs_mkdir(struct inode *dir, struct dentry *dentry, unsigned int flags, inode->i_gid = dir->i_gid; inode->i_mode &= S_ISGID; } - ctx = alloc_spu_context(); + ctx = alloc_spu_context(SPUFS_I(dir)->i_gang); /* XXX gang */ SPUFS_I(inode)->i_ctx = ctx; if (!ctx) goto out_iput; @@ -292,24 +301,177 @@ out: return ret; } +static int spufs_create_context(struct inode *inode, + struct dentry *dentry, + struct vfsmount *mnt, int flags, int mode) +{ + int ret; + + ret = spufs_mkdir(inode, dentry, flags, mode & S_IRWXUGO); + if (ret) + goto out_unlock; + + /* + * get references for dget and mntget, will be released + * in error path of *_open(). + */ + ret = spufs_context_open(dget(dentry), mntget(mnt)); + if (ret < 0) { + WARN_ON(spufs_rmdir(inode, dentry)); + mutex_unlock(&inode->i_mutex); + spu_forget(SPUFS_I(dentry->d_inode)->i_ctx); + goto out; + } + +out_unlock: + mutex_unlock(&inode->i_mutex); +out: + dput(dentry); + return ret; +} + +static int spufs_rmgang(struct inode *root, struct dentry *dir) +{ + /* FIXME: this fails if the dir is not empty, + which causes a leak of gangs. */ + return simple_rmdir(root, dir); +} + +static int spufs_gang_close(struct inode *inode, struct file *file) +{ + struct inode *parent; + struct dentry *dir; + int ret; + + dir = file->f_dentry; + parent = dir->d_parent->d_inode; + + ret = spufs_rmgang(parent, dir); + WARN_ON(ret); + + return dcache_dir_close(inode, file); +} + +struct file_operations spufs_gang_fops = { + .open = dcache_dir_open, + .release = spufs_gang_close, + .llseek = dcache_dir_lseek, + .read = generic_read_dir, + .readdir = dcache_readdir, + .fsync = simple_sync_file, +}; + +static int +spufs_mkgang(struct inode *dir, struct dentry *dentry, int mode) +{ + int ret; + struct inode *inode; + struct spu_gang *gang; + + ret = -ENOSPC; + inode = spufs_new_inode(dir->i_sb, mode | S_IFDIR); + if (!inode) + goto out; + + ret = 0; + if (dir->i_mode & S_ISGID) { + inode->i_gid = dir->i_gid; + inode->i_mode &= S_ISGID; + } + gang = alloc_spu_gang(); + SPUFS_I(inode)->i_ctx = NULL; + SPUFS_I(inode)->i_gang = gang; + if (!gang) + goto out_iput; + + inode->i_op = &spufs_dir_inode_operations; + inode->i_fop = &simple_dir_operations; + + d_instantiate(dentry, inode); + dget(dentry); + dir->i_nlink++; + dentry->d_inode->i_nlink++; + return ret; + +out_iput: + iput(inode); +out: + return ret; +} + +static int spufs_gang_open(struct dentry *dentry, struct vfsmount *mnt) +{ + int ret; + struct file *filp; + + ret = get_unused_fd(); + if (ret < 0) { + dput(dentry); + mntput(mnt); + goto out; + } + + filp = dentry_open(dentry, mnt, O_RDONLY); + if (IS_ERR(filp)) { + put_unused_fd(ret); + ret = PTR_ERR(filp); + goto out; + } + + filp->f_op = &spufs_gang_fops; + fd_install(ret, filp); +out: + return ret; +} + +static int spufs_create_gang(struct inode *inode, + struct dentry *dentry, + struct vfsmount *mnt, int mode) +{ + int ret; + + ret = spufs_mkgang(inode, dentry, mode & S_IRWXUGO); + if (ret) + goto out; + + /* + * get references for dget and mntget, will be released + * in error path of *_open(). + */ + ret = spufs_gang_open(dget(dentry), mntget(mnt)); + if (ret < 0) + WARN_ON(spufs_rmgang(inode, dentry)); + +out: + mutex_unlock(&inode->i_mutex); + dput(dentry); + return ret; +} + + static struct file_system_type spufs_type; -long spufs_create_thread(struct nameidata *nd, - unsigned int flags, mode_t mode) +long spufs_create(struct nameidata *nd, unsigned int flags, mode_t mode) { struct dentry *dentry; int ret; - /* need to be at the root of spufs */ ret = -EINVAL; - if (nd->dentry->d_sb->s_type != &spufs_type || - nd->dentry != nd->dentry->d_sb->s_root) + /* check if we are on spufs */ + if (nd->dentry->d_sb->s_type != &spufs_type) goto out; - /* all flags are reserved */ + /* don't accept undefined flags */ if (flags & (~SPU_CREATE_FLAG_ALL)) goto out; + /* only threads can be underneath a gang */ + if (nd->dentry != nd->dentry->d_sb->s_root) { + if ((flags & SPU_CREATE_GANG) || + !SPUFS_I(nd->dentry->d_inode)->i_gang) + goto out; + } + dentry = lookup_create(nd, 1); ret = PTR_ERR(dentry); if (IS_ERR(dentry)) @@ -320,22 +482,13 @@ long spufs_create_thread(struct nameidata *nd, goto out_dput; mode &= ~current->fs->umask; - ret = spufs_mkdir(nd->dentry->d_inode, dentry, flags, mode & S_IRWXUGO); - if (ret) - goto out_dput; - /* - * get references for dget and mntget, will be released - * in error path of *_open(). - */ - ret = spufs_context_open(dget(dentry), mntget(nd->mnt)); - if (ret < 0) { - WARN_ON(spufs_rmdir(nd->dentry->d_inode, dentry)); - mutex_unlock(&nd->dentry->d_inode->i_mutex); - spu_forget(SPUFS_I(dentry->d_inode)->i_ctx); - dput(dentry); - goto out; - } + if (flags & SPU_CREATE_GANG) + return spufs_create_gang(nd->dentry->d_inode, + dentry, nd->mnt, mode); + else + return spufs_create_context(nd->dentry->d_inode, + dentry, nd->mnt, flags, mode); out_dput: dput(dentry); |