sched/deadline: Don't use dubious signed bitfields

It doesn't cause a run-time bug, but these bitfields should be unsigned.
When it's signed ->dl_throttled is set to either 0 or -1, instead of
0 and 1 as expected.

The sched.h file is included into tons of places so Sparse generates
a flood of warnings like this:

  ./include/linux/sched.h:477:54: error: dubious one-bit signed bitfield

Reported-by: Matthew Wilcox <willy@infradead.org>
Reported-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Luca Abeni <luca.abeni@santannapisa.it>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-janitors@vger.kernel.org
Cc: luca abeni <luca.abeni@santannapisa.it>
Link: http://lkml.kernel.org/r/20171013070121.dzcncojuj2f4utij@mwanda
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/include/linux/sched.h b/include/linux/sched.h
index a5dc7c98b0a2e5d54814a2cd6d3ecc2ffd6f4ea1..21991d668d35231e625b95d99e2bd6826ba6a47e 100644 (file)
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -473,10 +473,10 @@ struct sched_dl_entity {
         * conditions between the inactive timer handler and the wakeup
         * code.
         */
-       int                             dl_throttled      : 1;
-       int                             dl_boosted        : 1;
-       int                             dl_yielded        : 1;
-       int                             dl_non_contending : 1;
+       unsigned int                    dl_throttled      : 1;
+       unsigned int                    dl_boosted        : 1;
+       unsigned int                    dl_yielded        : 1;
+       unsigned int                    dl_non_contending : 1;
 
        /*
         * Bandwidth enforcement timer. Each -deadline task has its