[PATCH v3 08/30] rhashtable: add schedule points

Stephen Hemminger
2018-09-13T14:58:40Z

From: Eric Dumazet <edumazet@google.com>

Rehashing and destroying large hash table takes a lot of time,
and happens in process context. It is safe to add cond_resched()
in rhashtable_rehash_table() and rhashtable_free_and_destroy()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit ae6da1f503abb5a5081f9f6c4a6881de97830f3e)
---
lib/rhashtable.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index 39215c724fc7..cebbcec877d7 100644
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c
@@ -364,6 +364,7 @@ static int rhashtable_rehash_table(struct rhashtable *ht)
err = rhashtable_rehash_chain(ht, old_hash);
if (err)
return err;
+ cond_resched();
}

/* Publish the new table pointer. */
@@ -1073,6 +1074,7 @@ void rhashtable_free_and_destroy(struct rhashtable *ht,
for (i = 0; i < tbl->size; i++) {
struct rhash_head *pos, *next;

+ cond_resched();
for (pos = rht_dereference(*rht_bucket(tbl, i), ht),
next = !rht_is_a_nulls(pos) ?
rht_dereference(pos->next, ht) : NULL;
--
2.18.0