On 11/05/2024 10:44, Greg KH wrote:
On Fri, May 10, 2024 at 04:01:01PM +0200, Przemek Kitszel wrote:
On 5/10/24 15:07, Greg KH wrote:
On Fri, May 10, 2024 at 02:54:49PM +0200, Przemek Kitszel wrote:
+static ssize_t auxiliary_irq_mode_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct auxiliary_irq_info *info =
+ container_of(attr, struct auxiliary_irq_info, sysfs_attr);
+
+ if (refcount_read(xa_load(&irqs, info->irq)) > 1)
refcount combined with xa? That feels wrong, why is refcount used for
this at all?
Not long ago I commented on similar usage for ice driver,
~"since you are locking anyway this could be a plain counter",
and author replied
~"additional semantics (like saturation) of refcount make me feel warm
and fuzzy" (sorry if misquoting too much).
That convinced me back then, so I kept quiet about that here.
But why is this being incremented / decremented at all? What is that
for?
[global]
This is just a counter, it is used to tell if given IRQ is shared or
exclusive. Hence there is a global xarray for that.
And my argument is for this case precisely.
[other]
There is also a separate xarray for each auxdev (IIRC) which is used as
generic dynamic container [that stores sysfs attrs], any other would
work (with different characteristics), but I see no problems with
picking xarray here.
Again, why is an xarray needed, why isn't this part of the auxdevice
structure to start with?
If I understand you correctly, you are referring to the xarray of the
auxdevice (not the global one).
If so, instead of xarray what can be used by the auxdevice?
thanks,
greg k-h
