Create a kmem cache of tracefs_inodes. To be more efficient, as there are lots of tracefs inodes, create its own cache. This also allows to see how many tracefs inodes have been created.
Add helper functions: tracefs_alloc_inode() tracefs_free_inode() get_tracefs()
Signed-off-by: Ajay Kaher akaher@vmware.com Co-developed-by: Steven Rostedt (VMware) rostedt@goodmis.org Signed-off-by: Steven Rostedt (VMware) rostedt@goodmis.org Tested-by: Ching-lin Yu chinglinyu@google.com --- fs/tracefs/inode.c | 39 +++++++++++++++++++++++++++++++++++++++ fs/tracefs/internal.h | 15 +++++++++++++++ 2 files changed, 54 insertions(+) create mode 100644 fs/tracefs/internal.h
diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c index 57ac8aa4a724..2508944cc4d8 100644 --- a/fs/tracefs/inode.c +++ b/fs/tracefs/inode.c @@ -21,13 +21,33 @@ #include <linux/parser.h> #include <linux/magic.h> #include <linux/slab.h> +#include "internal.h"
#define TRACEFS_DEFAULT_MODE 0700 +static struct kmem_cache *tracefs_inode_cachep __ro_after_init;
static struct vfsmount *tracefs_mount; static int tracefs_mount_count; static bool tracefs_registered;
+static struct inode *tracefs_alloc_inode(struct super_block *sb) +{ + struct tracefs_inode *ti; + + ti = kmem_cache_alloc(tracefs_inode_cachep, GFP_KERNEL); + if (!ti) + return NULL; + + ti->flags = 0; + + return &ti->vfs_inode; +} + +static void tracefs_free_inode(struct inode *inode) +{ + kmem_cache_free(tracefs_inode_cachep, get_tracefs(inode)); +} + static ssize_t default_read_file(struct file *file, char __user *buf, size_t count, loff_t *ppos) { @@ -346,6 +366,9 @@ static int tracefs_show_options(struct seq_file *m, struct dentry *root) }
static const struct super_operations tracefs_super_operations = { + .alloc_inode = tracefs_alloc_inode, + .free_inode = tracefs_free_inode, + .drop_inode = generic_delete_inode, .statfs = simple_statfs, .remount_fs = tracefs_remount, .show_options = tracefs_show_options, @@ -628,10 +651,26 @@ bool tracefs_initialized(void) return tracefs_registered; }
+static void init_once(void *foo) +{ + struct tracefs_inode *ti = (struct tracefs_inode *) foo; + + inode_init_once(&ti->vfs_inode); +} + static int __init tracefs_init(void) { int retval;
+ tracefs_inode_cachep = kmem_cache_create("tracefs_inode_cache", + sizeof(struct tracefs_inode), + 0, (SLAB_RECLAIM_ACCOUNT| + SLAB_MEM_SPREAD| + SLAB_ACCOUNT), + init_once); + if (!tracefs_inode_cachep) + return -ENOMEM; + retval = sysfs_create_mount_point(kernel_kobj, "tracing"); if (retval) return -EINVAL; diff --git a/fs/tracefs/internal.h b/fs/tracefs/internal.h new file mode 100644 index 000000000000..954ea005632b --- /dev/null +++ b/fs/tracefs/internal.h @@ -0,0 +1,15 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _TRACEFS_INTERNAL_H +#define _TRACEFS_INTERNAL_H + +struct tracefs_inode { + unsigned long flags; + void *private; + struct inode vfs_inode; +}; + +static inline struct tracefs_inode *get_tracefs(const struct inode *inode) +{ + return container_of(inode, struct tracefs_inode, vfs_inode); +} +#endif /* _TRACEFS_INTERNAL_H */