On Wed, Feb 01, 2023 at 05:06:22PM -0800, Bart Van Assche wrote:

On 2/1/23 15:59, Luis Chamberlain wrote:

quoted

My point was commit 85e0cbbb8a made blk_debugfs_root non-null always now
when debugfs is enabled for both request-based block drivers and for
make_request block drivers (multiqueue). My reading is that with your
patch blk_debugfs_root will not be created for request-based block
drivers.

Hi Luis,

The empty version of blk_mq_debugfs_init() in my patch is only selected if
CONFIG_BLK_DEBUG_FS=n. I think that my patch preserves the behavior that
/sys/kernel/debug/block/ is created independent of the type of request
queues that is created. Am I perhaps misunderstanding your feedback?

Yes, my point is prior to this patch the debugfs directory is created
even if you have CONFIG_BLK_DEBUG_FS=n and I've mentioned the commit
which describes why, but the skinnys is blktrace.

  Luis