UBI: create ubi_wl_entry slab on initialization

Similarly to ltree_entry_slab, it makes more sense to create
and destroy ubi_wl_entry slab on module initialization/exit.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

3 files changed, 44 insertions, 44 deletions

diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index 44c852144a9c..7f6820becf10 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -70,6 +70,10 @@ struct class *ubi_class;
 /* Slab cache for lock-tree entries */
 struct kmem_cache *ubi_ltree_slab;
 
+/* Slab cache for wear-leveling entries */
+struct kmem_cache *ubi_wl_entry_slab;
+
+
 /* "Show" method for files in '/<sysfs>/class/ubi/' */
 static ssize_t ubi_version_show(struct class *class, char *buf)
 {
@@ -732,6 +736,12 @@ static int __init ubi_init(void)
         if (!ubi_ltree_slab)
                 goto out_version;
 
+        ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
+                                                sizeof(struct ubi_wl_entry),
+                                                0, 0, NULL);
+        if (!ubi_wl_entry_slab)
+                goto out_ltree;
+
         /* Attach MTD devices */
         for (i = 0; i < mtd_devs; i++) {
                 struct mtd_dev_param *p = &mtd_dev_param[i];
@@ -747,6 +757,8 @@ static int __init ubi_init(void)
 out_detach:
         for (k = 0; k < i; k++)
                 detach_mtd_dev(ubi_devices[k]);
+        kmem_cache_destroy(ubi_wl_entry_slab);
+out_ltree:
         kmem_cache_destroy(ubi_ltree_slab);
 out_version:
         class_remove_file(ubi_class, &ubi_version);
@@ -762,6 +774,7 @@ static void __exit ubi_exit(void)
 
         for (i = 0; i < n; i++)
                 detach_mtd_dev(ubi_devices[i]);
+        kmem_cache_destroy(ubi_wl_entry_slab);
         kmem_cache_destroy(ubi_ltree_slab);
         class_remove_file(ubi_class, &ubi_version);
         class_destroy(ubi_class);
diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h
index 0f2ea81b3122..b7c93173e77b 100644
--- a/drivers/mtd/ubi/ubi.h
+++ b/drivers/mtd/ubi/ubi.h
@@ -98,6 +98,22 @@ extern int ubi_devices_cnt;
 extern struct ubi_device *ubi_devices[];
 
 /**
+ * struct ubi_wl_entry - wear-leveling entry.
+ * @rb: link in the corresponding RB-tree
+ * @ec: erase counter
+ * @pnum: physical eraseblock number
+ *
+ * This data structure is used in the WL unit. Each physical eraseblock has a
+ * corresponding &struct wl_entry object which may be kept in different
+ * RB-trees. See WL unit for details.
+ */
+struct ubi_wl_entry {
+        struct rb_node rb;
+        int ec;
+        int pnum;
+};
+
+/**
  * struct ubi_ltree_entry - an entry in the lock tree.
  * @rb: links RB-tree nodes
  * @vol_id: volume ID of the locked logical eraseblock
@@ -382,6 +398,7 @@ struct ubi_device {
 };
 
 extern struct kmem_cache *ubi_ltree_slab;
+extern struct kmem_cache *ubi_wl_entry_slab;
 extern struct file_operations ubi_cdev_operations;
 extern struct file_operations ubi_vol_cdev_operations;
 extern struct class *ubi_class;
diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c
index 6330c8cc72b5..a405d40faa23 100644
--- a/drivers/mtd/ubi/wl.c
+++ b/drivers/mtd/ubi/wl.c
@@ -117,21 +117,6 @@
 #define WL_MAX_FAILURES 32
 
 /**
- * struct ubi_wl_entry - wear-leveling entry.
- * @rb: link in the corresponding RB-tree
- * @ec: erase counter
- * @pnum: physical eraseblock number
- *
- * Each physical eraseblock has a corresponding &struct wl_entry object which
- * may be kept in different RB-trees.
- */
-struct ubi_wl_entry {
-        struct rb_node rb;
-        int ec;
-        int pnum;
-};
-
-/**
  * struct ubi_wl_prot_entry - PEB protection entry.
  * @rb_pnum: link in the @wl->prot.pnum RB-tree
  * @rb_aec: link in the @wl->prot.aec RB-tree
@@ -216,9 +201,6 @@ static int paranoid_check_in_wl_tree(struct ubi_wl_entry *e,
 #define paranoid_check_in_wl_tree(e, root)
 #endif
 
-/* Slab cache for wear-leveling entries */
-static struct kmem_cache *wl_entries_slab;
-
 /**
  * wl_tree_add - add a wear-leveling entry to a WL RB-tree.
  * @e: the wear-leveling entry to add
@@ -878,14 +860,14 @@ static int wear_leveling_worker(struct ubi_device *ubi, struct ubi_work *wrk,
                 dbg_wl("PEB %d was put meanwhile, erase", e2->pnum);
                 err = schedule_erase(ubi, e2, 0);
                 if (err) {
-                        kmem_cache_free(wl_entries_slab, e2);
+                        kmem_cache_free(ubi_wl_entry_slab, e2);
                         ubi_ro_mode(ubi);
                 }
         }
 
         err = schedule_erase(ubi, e1, 0);
         if (err) {
-                kmem_cache_free(wl_entries_slab, e1);
+                kmem_cache_free(ubi_wl_entry_slab, e1);
                 ubi_ro_mode(ubi);
         }
 
@@ -920,14 +902,14 @@ error:
                 dbg_wl("PEB %d was put meanwhile, erase", e1->pnum);
                 err = schedule_erase(ubi, e1, 0);
                 if (err) {
-                        kmem_cache_free(wl_entries_slab, e1);
+                        kmem_cache_free(ubi_wl_entry_slab, e1);
                         ubi_ro_mode(ubi);
                 }
         }
 
         err = schedule_erase(ubi, e2, 0);
         if (err) {
-                kmem_cache_free(wl_entries_slab, e2);
+                kmem_cache_free(ubi_wl_entry_slab, e2);
                 ubi_ro_mode(ubi);
         }
 
@@ -1020,7 +1002,7 @@ static int erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk,
         if (cancel) {
                 dbg_wl("cancel erasure of PEB %d EC %d", pnum, e->ec);
                 kfree(wl_wrk);
-                kmem_cache_free(wl_entries_slab, e);
+                kmem_cache_free(ubi_wl_entry_slab, e);
                 return 0;
         }
 
@@ -1049,7 +1031,7 @@ static int erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk,
 
         ubi_err("failed to erase PEB %d, error %d", pnum, err);
         kfree(wl_wrk);
-        kmem_cache_free(wl_entries_slab, e);
+        kmem_cache_free(ubi_wl_entry_slab, e);
 
         if (err == -EINTR || err == -ENOMEM || err == -EAGAIN ||
             err == -EBUSY) {
@@ -1294,7 +1276,7 @@ static void tree_destroy(struct rb_root *root)
                                         rb->rb_right = NULL;
                         }
 
-                        kmem_cache_free(wl_entries_slab, e);
+                        kmem_cache_free(ubi_wl_entry_slab, e);
                 }
         }
 }
@@ -1407,14 +1389,6 @@ int ubi_wl_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si)
                 return err;
         }
 
-        if (ubi_devices_cnt == 0) {
-                wl_entries_slab = kmem_cache_create("ubi_wl_entry_slab",
-                                                    sizeof(struct ubi_wl_entry),
-                                                    0, 0, NULL);
-                if (!wl_entries_slab)
-                        return -ENOMEM;
-        }
-
         err = -ENOMEM;
         ubi->lookuptbl = kzalloc(ubi->peb_count * sizeof(void *), GFP_KERNEL);
         if (!ubi->lookuptbl)
@@ -1423,7 +1397,7 @@ int ubi_wl_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si)
         list_for_each_entry_safe(seb, tmp, &si->erase, u.list) {
                 cond_resched();
 
-                e = kmem_cache_alloc(wl_entries_slab, GFP_KERNEL);
+                e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL);
                 if (!e)
                         goto out_free;
 
@@ -1431,7 +1405,7 @@ int ubi_wl_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si)
                 e->ec = seb->ec;
                 ubi->lookuptbl[e->pnum] = e;
                 if (schedule_erase(ubi, e, 0)) {
-                        kmem_cache_free(wl_entries_slab, e);
+                        kmem_cache_free(ubi_wl_entry_slab, e);
                         goto out_free;
                 }
         }
@@ -1439,7 +1413,7 @@ int ubi_wl_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si)
         list_for_each_entry(seb, &si->free, u.list) {
                 cond_resched();
 
-                e = kmem_cache_alloc(wl_entries_slab, GFP_KERNEL);
+                e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL);
                 if (!e)
                         goto out_free;
 
@@ -1453,7 +1427,7 @@ int ubi_wl_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si)
         list_for_each_entry(seb, &si->corr, u.list) {
                 cond_resched();
 
-                e = kmem_cache_alloc(wl_entries_slab, GFP_KERNEL);
+                e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL);
                 if (!e)
                         goto out_free;
 
@@ -1461,7 +1435,7 @@ int ubi_wl_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si)
                 e->ec = seb->ec;
                 ubi->lookuptbl[e->pnum] = e;
                 if (schedule_erase(ubi, e, 0)) {
-                        kmem_cache_free(wl_entries_slab, e);
+                        kmem_cache_free(ubi_wl_entry_slab, e);
                         goto out_free;
                 }
         }
@@ -1470,7 +1444,7 @@ int ubi_wl_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si)
                 ubi_rb_for_each_entry(rb2, seb, &sv->root, u.rb) {
                         cond_resched();
 
-                        e = kmem_cache_alloc(wl_entries_slab, GFP_KERNEL);
+                        e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL);
                         if (!e)
                                 goto out_free;
 
@@ -1510,8 +1484,6 @@ out_free:
         tree_destroy(&ubi->free);
         tree_destroy(&ubi->scrub);
         kfree(ubi->lookuptbl);
-        if (ubi_devices_cnt == 0)
-                kmem_cache_destroy(wl_entries_slab);
         return err;
 }
 
@@ -1541,7 +1513,7 @@ static void protection_trees_destroy(struct ubi_device *ubi)
                                         rb->rb_right = NULL;
                         }
 
-                        kmem_cache_free(wl_entries_slab, pe->e);
+                        kmem_cache_free(ubi_wl_entry_slab, pe->e);
                         kfree(pe);
                 }
         }
@@ -1565,8 +1537,6 @@ void ubi_wl_close(struct ubi_device *ubi)
         tree_destroy(&ubi->free);
         tree_destroy(&ubi->scrub);
         kfree(ubi->lookuptbl);
-        if (ubi_devices_cnt == 1)
-                kmem_cache_destroy(wl_entries_slab);
 }
 
 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID