On 5/8/19 9:16 PM, Benjamin Herrenschmidt wrote:
On Wed, 2019-05-08 at 18:19 -0700, Jae Hyun Yoo wrote:
I changed that from a bool because the maintainer of this code, Eddie
doesn't like adding of an additional flag. I'll change it back with
codes in the first submit:
https://www.spinics.net/lists/linux-media/msg148955.html
Eddie,
Please let me know if you have any objection on that.
Thats fine with me. I merely thought it was more conventional to use
flags rather than bools, but I may be mistaken.
Thanks!
Eddie
Ok, so random flags ... ugh.
Well, you can approach it either way. Have them all be bitops or all be
bool.
The tricky thing however is that if they are bitops you need to ensure
that they are *all* manipulated under the same lock. If not you have to
use the atomic bitops variants.
The reason I don't like that is that experience shows that most uses of
such atomic variants in drivers usually are failed attempts at papering
over broken locking.
If everything is covered by a lock, then using the non-atomic versions
is more efficient, but so is using bool (optionally with :1 bitfield
qualifiers to avoid wasting memory), which from a pure C language
perspective I think is more expressive of what you are doing and more
readable.
Cheers,
Ben.
