[PATCH v2 1/4] lib/rhashtable: simplify bucket_table_alloc()

[Davidlohr Bueso]

As of ce91f6ee5b3 (mm: kvmalloc does not fallback to vmalloc for incompatible gfp flag),
we can simplify the caller and trust kvzalloc() to just do the right thing. For the
case of the GFP_ATOMIC context, we can drop the __GFP_NORETRY flag for obvious reasons,
and for the __GFP_NOWARN case, however, it is changed such that the caller passes the
flag instead of making bucket_table_alloc() handle it.

This slightly changes the gfp flags passed on to nested_table_alloc() as it will now
also use GFP_ATOMIC | __GFP_NOWARN. However, I consider this a positive consequence
as for the same reasons we want nowarn semantics in bucket_table_alloc().

Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx>
---

v2:
- Changes based on Neil's concerns about keeping nowarn flag.
- Better changelog.


lib/rhashtable.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index 9427b5766134..083f871491a1 100644
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c
@@ -175,10 +175,7 @@ static struct bucket_table *bucket_table_alloc(struct rhashtable *ht,
	int i;

	size = sizeof(*tbl) + nbuckets * sizeof(tbl->buckets[0]);
-	if (gfp != GFP_KERNEL)
-		tbl = kzalloc(size, gfp | __GFP_NOWARN | __GFP_NORETRY);
-	else
-		tbl = kvzalloc(size, gfp);
+	tbl = kvzalloc(size, gfp);

	size = nbuckets;

@@ -459,7 +456,7 @@ static int rhashtable_insert_rehash(struct rhashtable *ht,

	err = -ENOMEM;

-	new_tbl = bucket_table_alloc(ht, size, GFP_ATOMIC);
+	new_tbl = bucket_table_alloc(ht, size, GFP_ATOMIC | __GFP_NOWARN);
	if (new_tbl == NULL)
		goto fail;

--
2.16.4