Re: [PATCH] xen/bitops: Fix break with in a for_each_set_bit() loop

["Roger Pau Monné" <roger.pau@citrix.com>]

On Thu, Nov 21, 2024 at 05:35:16PM +0000, Andrew Cooper wrote:
> On 21/11/2024 4:32 pm, Roger Pau Monné wrote:
> > On Thu, Nov 21, 2024 at 02:50:00PM +0000, Andrew Cooper wrote:
> >> diff --git a/xen/common/bitops.c b/xen/common/bitops.c
> >> index 91ae961440af..0edd62d25c28 100644
> >> --- a/xen/common/bitops.c
> >> +++ b/xen/common/bitops.c
> >> @@ -110,6 +110,22 @@ static void __init test_for_each_set_bit(void)
> >>  
> >>      if ( ull != ull_res )
> >>          panic("for_each_set_bit(uint64) expected %#"PRIx64", got %#"PRIx64"\n", ull, ull_res);
> >> +
> >> +    /* Check that we break from the middle of the loop */
> >> +    ui = HIDE(0x80001008U);
> >> +    ui_res = 0;
> >> +    for_each_set_bit ( i, ui )
> >> +    {
> >> +        static __initdata unsigned int count;
> > Preferably as you suggested without the static variable, I may suggest
> > that you use ui_tmp instead of plain tmp as the variable name?
> 
> For this, I'd prefer not to.
> 
> For ui, ul and ull, there are a pair of variables with precise usage.
> 
> This is one random number that gets as far as 2.  And it's test code.

My suggestion was on the basis that we might need to add more 'tmp'
variables of different types in the future maybe?  No strong opinion
anyway, I'm fine if you prefer to leave as plain 'tmp'.

Thanks, Roger.