Avoid open-coded atomic_dec on mm->context.active_cpus and use the
function made for it. Add CONFIG_DEBUG_VM underflow checking on the
counter.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230524060821.148015-3-npiggin@gmail.com
#define arch_clear_mm_cpumask_cpu(cpu, mm) \
do { \
if (cpumask_test_cpu(cpu, mm_cpumask(mm))) { \
- atomic_dec(&(mm)->context.active_cpus); \
+ dec_mm_active_cpus(mm); \
cpumask_clear_cpu(cpu, mm_cpumask(mm)); \
} \
} while (0)
static inline void dec_mm_active_cpus(struct mm_struct *mm)
{
+ VM_WARN_ON_ONCE(atomic_read(&mm->context.active_cpus) <= 0);
atomic_dec(&mm->context.active_cpus);
}
* that's what the caller expects.
*/
if (cpumask_test_cpu(cpu, mm_cpumask(mm))) {
- atomic_dec(&mm->context.active_cpus);
+ dec_mm_active_cpus(mm);
cpumask_clear_cpu(cpu, mm_cpumask(mm));
always_flush = true;
}