Re: [PATCH v5 02/10] eventfs: Implement tracefs_inode_cache

From: Ajay Kaher
Date: Wed Jul 26 2023 - 14:45:43 EST



>> 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..49b5e8949e1c
>> --- /dev/null
>> +++ b/fs/tracefs/internal.h
>> @@ -0,0 +1,19 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +#ifndef _TRACEFS_INTERNAL_H
>> +#define _TRACEFS_INTERNAL_H
>> +
>> +enum {
>> + TRACEFS_EVENT_INODE = BIT(1),
>> +};
>
> Let's not introduce the enum until it is used.


Ok, I will move this to v6 04/10.
Let me know once you will complete the review of v5.

-Ajay