sh: use clear_tasks_mm_cpumask()
Checking for process->mm is not enough because process' main thread may
exit or detach its mm via use_mm(), but other threads may still have a
valid mm.
To fix this we would need to use find_lock_task_mm(), which would walk up
all threads and returns an appropriate task (with task lock held).
clear_tasks_mm_cpumask() has the issue fixed, so let's use it.
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/sh/kernel/smp.c b/arch/sh/kernel/smp.c
index b86e9ca..2062aa8 100644
--- a/arch/sh/kernel/smp.c
+++ b/arch/sh/kernel/smp.c
@@ -123,7 +123,6 @@
int __cpu_disable(void)
{
unsigned int cpu = smp_processor_id();
- struct task_struct *p;
int ret;
ret = mp_ops->cpu_disable(cpu);
@@ -153,11 +152,7 @@
flush_cache_all();
local_flush_tlb_all();
- read_lock(&tasklist_lock);
- for_each_process(p)
- if (p->mm)
- cpumask_clear_cpu(cpu, mm_cpumask(p->mm));
- read_unlock(&tasklist_lock);
+ clear_tasks_mm_cpumask(cpu);
return 0;
}
