Regarding random grouop search start for allocation of inode.

[lokesh jaliminche <lokesh.jaliminche@xxxxxxxxx>]

hello folks,
                I am new to ext4 code. I was going through the
ext4-source for allocation of inode.
There is one thing that I did not understand while selection of groups
for inode allocation . I came across this code snippet which is part
of find_group_orlov function. question is, why group search start is
random ?

Code snippet:
==========
···if (qstr) {
»·······»·······»·······hinfo.hash_version = LDISKFS_DX_HASH_HALF_MD4;
»·······»·······»·······hinfo.seed = sbi->s_hash_seed;
»·······»·······»·······ldiskfsfs_dirhash(qstr->name, qstr->len, &hinfo);
»·······»·······»·······grp = hinfo.hash;
»·······»·······} else
»·······»·······»·······get_random_bytes(&grp, sizeof(grp));
»·······»·······parent_group = (unsigned)grp % ngroups;
»·······»·······for (i = 0; i < ngroups; i++) {
»·······»·······»·······g = (parent_group + i) % ngroups;
»·······»·······»·······get_orlov_stats(sb, g, flex_size, &stats);
»·······»·······»·······if (!stats.free_inodes)
»·······»·······»·······»·······continue;
»·······»·······»·······if (stats.used_dirs >= best_ndir)
»·······»·······»·······»·······continue;
»·······»·······»·······if (stats.free_inodes < avefreei)
»·······»·······»·······»·······continue;
»·······»·······»·······if (stats.free_blocks < avefreeb)
»·······»·······»·······»·······continue;
»·······»·······»·······grp = g;
»·······»·······»·······ret = 0;
»·······»·······»·······best_ndir = stats.used_dirs;
»·······»·······}

Thanks & Regards,
  Lokesh
��.n��������+%������w��{.n�����{�����ܨ}���Ơz�j:+v�����w����ޙ��&�)ߡ�a����z�ޗ���ݢj��w�f