workqueue: Convert to XArray

Signed-off-by: Matthew Wilcox <willy@infradead.org>

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 601d61150b65de35d5b27cddb87462ff943ca52c..c3d612e63761145e2e6722171c81a8f372c97895 100644 (file)
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -327,7 +327,7 @@ module_param_named(debug_force_rr_cpu, wq_debug_force_rr_cpu, bool, 0644);
 /* the per-cpu worker pools */
 static DEFINE_PER_CPU_SHARED_ALIGNED(struct worker_pool [NR_STD_WORKER_POOLS], cpu_worker_pools);
 
-static DEFINE_IDR(worker_pool_idr);    /* PR: idr of all pools */
+static DEFINE_XARRAY_ALLOC(worker_pools);      /* PR: array of all pools */
 
 /* PL: hash of all unbound pools keyed by pool->attrs */
 static DEFINE_HASHTABLE(unbound_pool_hash, UNBOUND_POOL_HASH_ORDER);
@@ -393,7 +393,7 @@ static void workqueue_sysfs_unregister(struct workqueue_struct *wq);
  * ignored.
  */
 #define for_each_pool(pool, pi)                                                \
-       idr_for_each_entry(&worker_pool_idr, pool, pi)                  \
+       xa_for_each(&worker_pools, pi, pool)                            \
                if (({ assert_rcu_or_pool_mutex(); false; })) { }       \
                else
 
@@ -535,17 +535,10 @@ static inline void debug_work_deactivate(struct work_struct *work) { }
  */
 static int worker_pool_assign_id(struct worker_pool *pool)
 {
-       int ret;
-
        lockdep_assert_held(&wq_pool_mutex);
 
-       ret = idr_alloc(&worker_pool_idr, pool, 0, WORK_OFFQ_POOL_NONE,
-                       GFP_KERNEL);
-       if (ret >= 0) {
-               pool->id = ret;
-               return 0;
-       }
-       return ret;
+       return xa_alloc(&worker_pools, &pool->id, pool,
+                       XA_LIMIT(0, WORK_OFFQ_POOL_NONE - 1), GFP_KERNEL);
 }
 
 /**
@@ -722,7 +715,7 @@ static struct worker_pool *get_work_pool(struct work_struct *work)
        if (pool_id == WORK_OFFQ_POOL_NONE)
                return NULL;
 
-       return idr_find(&worker_pool_idr, pool_id);
+       return xa_load(&worker_pools, pool_id);
 }
 
 /**
@@ -3526,8 +3519,7 @@ static void put_unbound_pool(struct worker_pool *pool)
                return;
 
        /* release id and unhash */
-       if (pool->id >= 0)
-               idr_remove(&worker_pool_idr, pool->id);
+       xa_erase(&worker_pools, pool->id);
        hash_del(&pool->hash_node);
 
        /*
@@ -4700,7 +4692,7 @@ void show_workqueue_state(void)
        struct workqueue_struct *wq;
        struct worker_pool *pool;
        unsigned long flags;
-       int pi;
+       unsigned long pi;
 
        rcu_read_lock();
 
@@ -4989,7 +4981,7 @@ int workqueue_online_cpu(unsigned int cpu)
 {
        struct worker_pool *pool;
        struct workqueue_struct *wq;
-       int pi;
+       unsigned long pi;
 
        mutex_lock(&wq_pool_mutex);
 
@@ -5695,7 +5687,7 @@ static void wq_watchdog_timer_fn(struct timer_list *unused)
        unsigned long thresh = READ_ONCE(wq_watchdog_thresh) * HZ;
        bool lockup_detected = false;
        struct worker_pool *pool;
-       int pi;
+       unsigned long pi;
 
        if (!thresh)
                return;
@@ -5849,7 +5841,7 @@ static void __init wq_numa_init(void)
  *
  * This is the first half of two-staged workqueue subsystem initialization
  * and invoked as soon as the bare basics - memory allocation, cpumasks and
- * idr are up.  It sets up all the data structures and system workqueues
+ * xarray are up.  It sets up all the data structures and system workqueues
  * and allows early boot code to create workqueues and queue/cancel work
  * items.  Actual work item execution starts only after kthreads can be
  * created and scheduled right before early initcalls.