On Thu, Jan 12, 2017 at 12:19:37PM -0700, Andreas Dilger wrote:

On Jan 11, 2017, at 8:49 PM, Theodore Ts'o [off-list ref] wrote:

quoted

In order to test the inode extra isize expansion code, it is useful to
be able to easily create file systems that have inodes with extra
isize values smaller than the current desired value.

Rather than adding all of the debug hooks as mount options, wouldn't it
make more sense to add tunables via debugfs or as an attr_extra_isize or
similar?

Debugfs would be lot more complicated to implement, and especially if
we had to set up a separate directory hierarchy for each file system.
And both debugfs and setting it up in sysfs would mean more runtime
memory in use for each file system this is mounted.  The mount option
is actually one of the simpler, lighter weight ways of adding the
debug hook.

What's the objection (or objections) you have to using mount options?

       	   	   	     	      - Ted