diff options
authorLinus Torvalds <torvalds@linux-foundation.org>2019-10-02 16:16:07 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-10-02 16:16:07 -0700
commit0f1a7b3fac0583083ca19d4de47403511ced3521 (patch)
parent5021b9182ee805603e3b180220a929af7bd4b960 (diff)
timer-of: don't use conditional expression with mixed 'void' types
Randy Dunlap reports on the sparse list that sparse warns about this expression: of_irq->percpu ? free_percpu_irq(of_irq->irq, clkevt) : free_irq(of_irq->irq, clkevt); and honestly, sparse is correct to warn. The return type of free_percpu_irq() is 'void', while free_irq() returns a 'const void *' that is the devname argument passed in to the request_irq(). You can't mix a void type with a non-void types in a conditional expression according to the C standard. It so happens that gcc seems to accept it - and the resulting type of the expression is void - but there's really no reason for the kernel to have this kind of non-standard expression with no real upside. The natural way to write that expression is with an if-statement: if (of_irq->percpu) free_percpu_irq(of_irq->irq, clkevt); else free_irq(of_irq->irq, clkevt); which is more legible anyway. I'm not sure why that timer-of code seems to have this odd pattern. It does the same at allocation time, but at least there the types match, and it makes sense as an expression. Reported-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/clocksource/timer-of.c b/drivers/clocksource/timer-of.c
index d8c2bd4391d0..11ff701ff4bb 100644
--- a/drivers/clocksource/timer-of.c
+++ b/drivers/clocksource/timer-of.c
@@ -25,7 +25,9 @@ static __init void timer_of_irq_exit(struct of_timer_irq *of_irq)
struct clock_event_device *clkevt = &to->clkevt;
- of_irq->percpu ? free_percpu_irq(of_irq->irq, clkevt) :
+ if (of_irq->percpu)
+ free_percpu_irq(of_irq->irq, clkevt);
+ else
free_irq(of_irq->irq, clkevt);