kern/kmem: remove the KMEM_CACHE_NORECLAIM flag

Don't encourage anyone to use non reclaimable pools of resources, it's
a Bad Thing To Do.

2 files changed, 8 insertions, 24 deletions

diff --git a/kern/kmem.c b/kern/kmem.c
index be2c78c7..af3eccac 100644
--- a/kern/kmem.c
+++ b/kern/kmem.c
@@ -270,7 +270,6 @@ kmem_slab_create(struct kmem_cache *cache, size_t color)
         return NULL;
 
     if (cache->flags & KMEM_CF_SLAB_EXTERNAL) {
-        assert(!(cache->flags & KMEM_CF_NO_RECLAIM));
         slab = kmem_cache_alloc(&kmem_slab_cache);
 
         if (slab == NULL) {
@@ -543,12 +542,6 @@ kmem_cache_init(struct kmem_cache *cache, const char *name, size_t obj_size,
     if (flags & KMEM_CACHE_NOCPUPOOL)
         cache->flags |= KMEM_CF_NO_CPU_POOL;
 
-    if (flags & KMEM_CACHE_NORECLAIM) {
-        assert(slab_free_fn == NULL);
-        flags |= KMEM_CACHE_NOOFFSLAB;
-        cache->flags |= KMEM_CF_NO_RECLAIM;
-    }
-
     if (flags & KMEM_CACHE_VERIFY)
         cache->flags |= KMEM_CF_VERIFY;
 
@@ -1257,7 +1250,6 @@ kmem_info(void)
 {
     struct kmem_cache *cache, *cache_stats;
     size_t mem_usage, mem_reclaimable;
-    int not_reclaimable;
 
     cache_stats = kmem_alloc(sizeof(*cache_stats));
 
@@ -1275,7 +1267,6 @@ kmem_info(void)
 
     list_for_each_entry(&kmem_cache_list, cache, node) {
         /* mutex_lock(&cache->mutex); */
-        not_reclaimable = cache->flags & KMEM_CF_NO_RECLAIM;
         cache_stats->obj_size = cache->obj_size;
         cache_stats->slab_size = cache->slab_size;
         cache_stats->bufs_per_slab = cache->bufs_per_slab;
@@ -1287,12 +1278,8 @@ kmem_info(void)
         /* mutex_unlock(&cache->mutex); */
 
         mem_usage = (cache_stats->nr_slabs * cache_stats->slab_size) >> 10;
-
-        if (not_reclaimable)
-            mem_reclaimable = 0;
-        else
-            mem_reclaimable =
-                (cache_stats->nr_free_slabs * cache_stats->slab_size) >> 10;
+        mem_reclaimable =
+            (cache_stats->nr_free_slabs * cache_stats->slab_size) >> 10;
 
         printk("kmem: %-19s %6zu %3zuk  %4lu %6lu %6lu %7zuk %10zuk\n",
                cache_stats->name, cache_stats->obj_size,
diff --git a/kern/kmem.h b/kern/kmem.h
index f0beec11..169497c2 100644
--- a/kern/kmem.h
+++ b/kern/kmem.h
@@ -182,11 +182,10 @@ typedef void (*kmem_slab_free_fn_t)(unsigned long, size_t);
  *
  * The flags don't change once set and can be tested without locking.
  */
-#define KMEM_CF_NO_CPU_POOL     0x01    /* CPU pool layer disabled */
-#define KMEM_CF_SLAB_EXTERNAL   0x02    /* Slab data is off slab */
-#define KMEM_CF_NO_RECLAIM      0x04    /* Slabs are not reclaimable */
-#define KMEM_CF_VERIFY          0x08    /* Debugging facilities enabled */
-#define KMEM_CF_DIRECT          0x10    /* No buf-to-slab tree lookup */
+#define KMEM_CF_NO_CPU_POOL     0x1 /* CPU pool layer disabled */
+#define KMEM_CF_SLAB_EXTERNAL   0x2 /* Slab data is off slab */
+#define KMEM_CF_VERIFY          0x4 /* Debugging facilities enabled */
+#define KMEM_CF_DIRECT          0x8 /* No buf-to-slab tree lookup */
 
 /*
  * Cache of objects.
@@ -237,15 +236,13 @@ struct kmem_cache {
  */
 #define KMEM_CACHE_NOCPUPOOL    0x1 /* Don't use the per-cpu pools */
 #define KMEM_CACHE_NOOFFSLAB    0x2 /* Don't allocate external slab data */
-#define KMEM_CACHE_NORECLAIM    0x4 /* Never give slabs back to their source,
-                                       implies KMEM_CACHE_NOOFFSLAB */
-#define KMEM_CACHE_VERIFY       0x8 /* Use debugging facilities */
+#define KMEM_CACHE_VERIFY       0x4 /* Use debugging facilities */
 
 /*
  * Initialize a cache.
  *
  * If a slab allocation/free function pointer is NULL, the default backend
- * (vm_kmem on the kmem map) is used for the allocation/free action.
+ * (vm_kmem on the kernel map) is used for the allocation/free action.
  */
 void kmem_cache_init(struct kmem_cache *cache, const char *name,
                      size_t obj_size, size_t align, kmem_cache_ctor_t ctor,