Hi Matthew,
On Tue, Feb 20, 2018 at 7:07 PM, Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote:
> On Tue, Feb 20, 2018 at 04:52:46AM -0800, Matthew Wilcox wrote:
>> On Tue, Feb 20, 2018 at 04:25:15PM +0530, Souptick Joarder wrote:
>> > On Tue, Feb 20, 2018 at 2:38 PM, Minchan Kim <minchan@xxxxxxxxxx> wrote:
>> > > Yub, bool could be more appropriate. However, there are lots of other places
>> > > in kernel where use int instead of bool.
>> > > If we fix every such places with each patch, it would be very painful.
>> > > If you believe it's really worth, it would be better to find/fix every
>> > > such places in one patch. But I'm not sure it's worth.
>> > >
>> >
>> > Sure, I will create patch series and send it.
>>
>> Please don't. If you're touching a function for another reason, it's
>> fine to convert it to return bool. A series of patches converting every
>> function in the kernel that could be converted will not make friends.
>
> ... but if you're looking for something to do, here's something from my
> TODO list that's in the same category.
Thanks. I would like to take it.
>
> The vm_ops fault, huge_fault, page_mkwrite and pfn_mkwrite handlers are
> currently defined to return an int (see linux/mm.h). Unlike the majority
> of functions which return int, these functions are supposed to return
> one or more of the VM_FAULT flags. There's general agreement that this
> should become a new typedef, vm_fault_t. We can do a gradual conversion;
> start off by adding
>
> typedef int vm_fault_t;
>
> to linux/mm.h. Then the individual drivers can be converted (one patch
> per driver) to return vm_fault_t from those handlers (probably about
> 180 patches, so take it slowly). Once all drivers are converted, we
> can change that typedef to:
>
> typedef enum {
> VM_FAULT_OOM = 1,
> VM_FAULT_SIGBUS = 2,
> VM_FAULT_MAJOR = 4,
> ...
> } vm_fault_t;
>
> and then the compiler will warn if anyone tries to introduce a new handler
> that returns int.
>
Let me go through the shared details and will reply you back
before making any changes.
-Souptick
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
