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Re: [PATCH 1/1] workqueue: use type int instead of bool to index array

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On 2017/9/6 22:33, Tejun Heo wrote:
> Hello,
> 
> On Wed, Sep 06, 2017 at 11:34:14AM +0800, zijun_hu wrote:
>> From: zijun_hu <zijun_hu@htc.com>
>>
>> type bool is used to index three arrays in alloc_and_link_pwqs()
>> it doesn't look like conventional.
>>
>> it is fixed by using type int to index the relevant arrays.
> 
> bool is a uint type which can be either 0 or 1.  I don't see what the
> benefit of this patch is.q
> 
bool is NOT a uint type now, it is a new type introduced by gcc, it is
rather different with "typedef int bool" historically
see following code segments for more info about type bool
	bool v = 0x10;
	printf("v = %d\n", v);
the output is v = 1.

it maybe cause a invalid array index if bool is represented as uint
bool highpri = wq->flags & WQ_HIGHPRI; WQ_HIGHPRI = 1 << 4,
@highpri maybe 16, but the number of array elements is 2.

bool is a logic value, the valid value is true or false. 
indexing array by type bool is not a good program custom

it is more extendable to use type int, type bool maybe is improper if the number of
array elements is extended to more than 2 in future

besides, the relevant array is indexed by type int in many other places of the
same source file. this patch can keep consistency
> 

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[PATCH 1/1] workqueue: use type int instead of bool to index array zijun_hu <zijun_hu@zoho.com> - 2017-09-06 06:00 +0200
  Re: [PATCH 1/1] workqueue: use type int instead of bool to index  array Tejun Heo <tj@kernel.org> - 2017-09-06 16:40 +0200
    Re: [PATCH 1/1] workqueue: use type int instead of bool to index  array zijun_hu <zijun_hu@zoho.com> - 2017-09-06 18:10 +0200
      Re: [PATCH 1/1] workqueue: use type int instead of bool to index  array Tejun Heo <tj@kernel.org> - 2017-09-06 18:50 +0200
        Re: [PATCH 1/1] workqueue: use type int instead of bool to index  array zijun_hu <zijun_hu@zoho.com> - 2017-09-06 19:10 +0200
          Re: [PATCH 1/1] workqueue: use type int instead of bool to index  array Tejun Heo <tj@kernel.org> - 2017-09-06 19:30 +0200

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