[patch 34/39] tick: broadcast-hrtimer: Remove overly clever return value abuse

From: Thomas Gleixner
Date: Tue Apr 14 2015 - 17:10:35 EST


The assignment of bc_moved in the conditional construct relies on the
fact that in the case of hrtimer_start() invocation the return value
is always 0. It took me a while to understand it.

We want to get rid of the hrtimer_start() return value. Open code the
logic which makes it readable as well.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Preeti U Murthy <preeti@xxxxxxxxxxxxxxxxxx>
---
kernel/time/tick-broadcast-hrtimer.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

Index: tip/kernel/time/tick-broadcast-hrtimer.c
===================================================================
--- tip.orig/kernel/time/tick-broadcast-hrtimer.c
+++ tip/kernel/time/tick-broadcast-hrtimer.c
@@ -66,9 +66,11 @@ static int bc_set_next(ktime_t expires,
* hrtimer_{start/cancel} functions call into tracing,
* calls to these functions must be bound within RCU_NONIDLE.
*/
- RCU_NONIDLE(bc_moved = (hrtimer_try_to_cancel(&bctimer) >= 0) ?
- !hrtimer_start(&bctimer, expires, HRTIMER_MODE_ABS_PINNED) :
- 0);
+ RCU_NONIDLE({
+ bc_moved = hrtimer_try_to_cancel(&bctimer) >= 0;
+ if (bc_moved)
+ hrtimer_start(&bctimer, expires,
+ HRTIMER_MODE_ABS_PINNED);});
if (bc_moved) {
/* Bind the "device" to the cpu */
bc->bound_on = smp_processor_id();


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