struct work_struct free_work;
#endif
spinlock_t lock;
+ atomic_t compaction_in_progress;
};
struct zspage {
struct size_class *class;
unsigned long pages_freed = 0;
+ /*
+ * Pool compaction is performed under pool->lock so it is basically
+ * single-threaded. Having more than one thread in __zs_compact()
+ * will increase pool->lock contention, which will impact other
+ * zsmalloc operations that need pool->lock.
+ */
+ if (atomic_xchg(&pool->compaction_in_progress, 1))
+ return 0;
+
for (i = ZS_SIZE_CLASSES - 1; i >= 0; i--) {
class = pool->size_class[i];
if (class->index != i)
pages_freed += __zs_compact(pool, class);
}
atomic_long_add(pages_freed, &pool->stats.pages_compacted);
+ atomic_set(&pool->compaction_in_progress, 0);
return pages_freed;
}
init_deferred_free(pool);
spin_lock_init(&pool->lock);
+ atomic_set(&pool->compaction_in_progress, 0);
pool->name = kstrdup(name, GFP_KERNEL);
if (!pool->name)