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Subject[PATCH 4/4] sched/deadline: use C bitfields for the state flags
Date
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>
---
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
--
2.7.4
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