On 5/28/19 1:08 PM, Vladimir Davydov
wrote:
static void flush_memcg_workqueue(struct kmem_cache *s)
{
+ /*
+ * memcg_params.dying is synchronized using slab_mutex AND
+ * memcg_kmem_wq_lock spinlock, because it's not always
+ * possible to grab slab_mutex.
+ */
mutex_lock(&slab_mutex);
+ spin_lock(&memcg_kmem_wq_lock);
s->memcg_params.dying = true;
+ spin_unlock(&memcg_kmem_wq_lock);
I would completely switch from the mutex to the new spin lock -
acquiring them both looks weird.
mutex_unlock(&slab_mutex);
/*
There are places where the slab_mutex is held and sleeping
functions like kvzalloc() are called. I understand that taking
both mutex and spinlocks look ugly, but converting all the
slab_mutex critical sections to spinlock critical sections will be
a major undertaking by itself. So I would suggest leaving that for
now.
Cheers,
Longman
