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SubjectRe: [PATCH 4/4] sched/deadline: use C bitfields for the state flags
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On 09/07/2017 12:09 PM, luca abeni wrote:
> Ask the compiler to use a single bit for storing true / false values,
> instead of wasting the size of a whole int value.
> Tested with gcc 5.4.0 on x86_64, and the compiler produces the expected
> Assembly (similar to the Assembly code generated when explicitly accessing
> the bits with bitmasks, "&" and "|").
>
> Signed-off-by: luca abeni <luca.abeni@santannapisa.it>

Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com>

-- Daniel
> ---
> include/linux/sched.h | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/include/linux/sched.h b/include/linux/sched.h
> index 68b3833..e03cc69 100644
> --- a/include/linux/sched.h
> +++ b/include/linux/sched.h
> @@ -472,10 +472,10 @@ struct sched_dl_entity {
> * conditions between the inactive timer handler and the wakeup
> * code.
> */
> - int dl_throttled;
> - int dl_boosted;
> - int dl_yielded;
> - int dl_non_contending;
> + int dl_throttled : 1;
> + int dl_boosted : 1;
> + int dl_yielded : 1;
> + int dl_non_contending : 1;
>
> /*
> * Bandwidth enforcement timer. Each -deadline task has its
>

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