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>

diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index 5e04403e25f5503f2372633b7c765285503ad908..220a11a13d4046a709efd3db69e2274ea2fa7562 100644 (file)
--- 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;