Re: [PATCH v2 1/4] lib/rhashtable: simplify bucket_table_alloc()
From: Davidlohr Bueso <dave@stgolabs.net>
Date: 2018-06-22 18:35:12
Also in:
lkml
Subsystem:
library code, rhashtable, the rest · Maintainers:
Andrew Morton, Thomas Graf, Herbert Xu, Linus Torvalds
On Fri, 22 Jun 2018, Davidlohr Bueso wrote:
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().
If this is not acceptable, we can just keep the caller's current semantics - the atomic flag could also be labeled 'rehash' or something considering that it comes only from insert_rehash() when we get EAGAIN after trying to insert the first time:
diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index 9427b5766134..18740b052aec 100644
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c@@ -172,17 +172,15 @@ static struct bucket_table *bucket_table_alloc(struct rhashtable *ht, { struct bucket_table *tbl = NULL; size_t size, max_locks; + bool atomic = (gfp == GFP_ATOMIC); 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, atomic ? gfp | __GFP_NOWARN : gfp); size = nbuckets; - if (tbl == NULL && gfp != GFP_KERNEL) { + if (tbl == NULL && atomic) { tbl = nested_bucket_table_alloc(ht, nbuckets, gfp); nbuckets = 0; }