vfs_caches_init_early()

<kernel v5.0>

VFS 캐시 초기화

vfs_caches_init_early()

fs/dcache.c

void __init vfs_caches_init_early(void)
{
        int i;

        for (i = 0; i < ARRAY_SIZE(in_lookup_hashtable); i++)
                INIT_HLIST_BL_HEAD(&in_lookup_hashtable[i]);

        dcache_init_early();
        inode_init_early();
}

vfs(virtual file system)에서 사용되는 각종 해시 테이블들을 초기화한다.

 

dcache_init_early()

fs/dcache.c

static void __init dcache_init_early(void)
{
        /* If hashes are distributed across NUMA nodes, defer
         * hash allocation until vmalloc space is available.
         */
        if (hashdist)
                return;

        dentry_hashtable =
                alloc_large_system_hash("Dentry cache",
                                        sizeof(struct hlist_bl_head),
                                        dhash_entries,
                                        13,
                                        HASH_EARLY | HASH_ZERO,
                                        &d_hash_shift,
                                        NULL,
                                        0,
                                        0);
        d_hash_shift = 32 - d_hash_shift;
}

Dentry 캐시 해시 리스트를 memblock에 early 할당 받고 초기화한다.

 

inode_init_early()

fs/inode.c

/*
 * Initialize the waitqueues and inode hash table.
 */

void __init inode_init_early(void)
{
        /* If hashes are distributed across NUMA nodes, defer
         * hash allocation until vmalloc space is available.
         */
        if (hashdist)
                return;

        inode_hashtable =
                alloc_large_system_hash("Inode-cache",
                                        sizeof(struct hlist_head),
                                        ihash_entries,
                                        14,
                                        HASH_EARLY | HASH_ZERO,
                                        &i_hash_shift,
                                        &i_hash_mask,
                                        0,
                                        0);
}

Inode 캐시 해시 리스트를 memblock에 early 할당 받고 초기화한다.

 

참고

• alloc_large_system_hash() | 문c