[PATCH 08/12] lib/rhashtable: simplify bucket_table_alloc()

From: Manfred Spraul
Date: Mon Jul 09 2018 - 11:13:34 EST


From: Davidlohr Bueso <dave@xxxxxxxxxxxx>

As of commit ce91f6ee5b3b ("mm: kvmalloc does not fallback to vmalloc for
incompatible gfp flags") 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>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>

(commit id extended to 12 digits, line wraps updated)
Signed-off-by: Manfred Spraul <manfred@xxxxxxxxxxxxxxxx>
---
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;

--
2.17.1