genirq: Make - vs ?: precedence explicit

Noticed with a Clang build. This improves the readability of the ?:
expression, as it has lower precedence than the - expression. Show explicitly that - is evaluated first.

Cc Thomas Gleixner <[email protected]>

Signed-off-by Kees Cook <[email protected]>

---
 kernel/irq/matrix.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

kernel/irq/matrix.c +0 -0

index a3cbbc8191c5..7df2480005f8 100644

Quoted 15 lines · Kees Cook

Noticed with a Clang build. This improves the readability of the ?:
expression, as it has lower precedence than the - expression. Show explicitly that - is evaluated first.

Cc Thomas Gleixner <[email protected]>

Signed-off-by Kees Cook <[email protected]>

---
 kernel/irq/matrix.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

kernel/irq/matrix.c +0 -0

index a3cbbc8191c5..7df2480005f8 100644

kernel/irq/matrix.c unsigned int irq_matrix_available(struct irq_matrix *m, bool cpudown) · line 388

Quoted 6 lines

kernel/irq/matrix.c +1 -1

@@ -384,7 +384,7 @@ unsigned int irq_matrix_available(struct irq_matrix *m, bool cpudown)
 {
 	struct cpumap *cm = this_cpu_ptr(m->maps);
 
-	return m->global_available - cpudown ? cm->available : 0;
+	return (m->global_available - cpudown) ? cm->available : 0;
 }

I see that this got applied, and that doesn't change the semantics of the code. But surely the code is and was buggy, right? From the kernel doc, I'm pretty sure the idea is to subtract cm->available if cpudown is true, otherwise subtract 0, i.e.

  return m->global_available - (cpudown ? cm->available : 0);