rhashtable: Allow GFP_ATOMIC bucket table allocation

This patch adds the ability to allocate bucket table with GFP_ATOMIC
instead of GFP_KERNEL.  This is needed when we perform an immediate
rehash during insertion.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 15 insertions, 11 deletions

diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index 5e04403e25f5..220a11a13d40 100644
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c
@@ -58,7 +58,8 @@ EXPORT_SYMBOL_GPL(lockdep_rht_bucket_is_held);
 #endif
 
 
-static int alloc_bucket_locks(struct rhashtable *ht, struct bucket_table *tbl)
+static int alloc_bucket_locks(struct rhashtable *ht, struct bucket_table *tbl,
+                              gfp_t gfp)
 {
         unsigned int i, size;
 #if defined(CONFIG_PROVE_LOCKING)
@@ -75,12 +76,13 @@ static int alloc_bucket_locks(struct rhashtable *ht, struct bucket_table *tbl)
 
         if (sizeof(spinlock_t) != 0) {
 #ifdef CONFIG_NUMA
-                if (size * sizeof(spinlock_t) > PAGE_SIZE)
+                if (size * sizeof(spinlock_t) > PAGE_SIZE &&
+                    gfp == GFP_KERNEL)
                         tbl->locks = vmalloc(size * sizeof(spinlock_t));
                 else
 #endif
                 tbl->locks = kmalloc_array(size, sizeof(spinlock_t),
-                                           GFP_KERNEL);
+                                           gfp);
                 if (!tbl->locks)
                         return -ENOMEM;
                 for (i = 0; i < size; i++)
@@ -105,23 +107,25 @@ static void bucket_table_free_rcu(struct rcu_head *head)
 }
 
 static struct bucket_table *bucket_table_alloc(struct rhashtable *ht,
-                                               size_t nbuckets)
+                                               size_t nbuckets,
+                                               gfp_t gfp)
 {
         struct bucket_table *tbl = NULL;
         size_t size;
         int i;
 
         size = sizeof(*tbl) + nbuckets * sizeof(tbl->buckets[0]);
-        if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER))
-                tbl = kzalloc(size, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY);
-        if (tbl == NULL)
+        if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER) ||
+            gfp != GFP_KERNEL)
+                tbl = kzalloc(size, gfp | __GFP_NOWARN | __GFP_NORETRY);
+        if (tbl == NULL && gfp == GFP_KERNEL)
                 tbl = vzalloc(size);
         if (tbl == NULL)
                 return NULL;
 
         tbl->size = nbuckets;
 
-        if (alloc_bucket_locks(ht, tbl) < 0) {
+        if (alloc_bucket_locks(ht, tbl, gfp) < 0) {
                 bucket_table_free(tbl);
                 return NULL;
         }
@@ -288,7 +292,7 @@ static int rhashtable_expand(struct rhashtable *ht)
 
         old_tbl = rhashtable_last_table(ht, old_tbl);
 
-        new_tbl = bucket_table_alloc(ht, old_tbl->size * 2);
+        new_tbl = bucket_table_alloc(ht, old_tbl->size * 2, GFP_KERNEL);
         if (new_tbl == NULL)
                 return -ENOMEM;
 
@@ -332,7 +336,7 @@ static int rhashtable_shrink(struct rhashtable *ht)
         if (rht_dereference(old_tbl->future_tbl, ht))
                 return -EEXIST;
 
-        new_tbl = bucket_table_alloc(ht, size);
+        new_tbl = bucket_table_alloc(ht, size, GFP_KERNEL);
         if (new_tbl == NULL)
                 return -ENOMEM;
 
@@ -689,7 +693,7 @@ int rhashtable_init(struct rhashtable *ht,
                 }
         }
 
-        tbl = bucket_table_alloc(ht, size);
+        tbl = bucket_table_alloc(ht, size, GFP_KERNEL);
         if (tbl == NULL)
                 return -ENOMEM;