diff options
| author | Alexander Duyck <alexander.h.duyck@intel.com> | 2017-03-24 20:07:53 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-03-25 06:49:30 +0300 |
| commit | 545cd5e5ec5477c325e4098b6fd21213dceda408 (patch) | |
| tree | 43a2aaa0f59d8721b8ab25d0f52749f798f42122 /net/core/dev.c | |
| parent | dcb421f4279f362c3eef7479616c76588b74d782 (diff) | |
| download | linux-545cd5e5ec5477c325e4098b6fd21213dceda408.tar.xz | |
net: Busy polling should ignore sender CPUs
This patch is a cleanup/fix for NAPI IDs following the changes that made it
so that sender_cpu and napi_id were doing a better job of sharing the same
location in the sk_buff.
One issue I found is that we weren't validating the napi_id as being valid
before we started trying to setup the busy polling. This change corrects
that by using the MIN_NAPI_ID value that is now used in both allocating the
NAPI IDs, as well as validating them.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/dev.c')
| -rw-r--r-- | net/core/dev.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index 7869ae3837ca..ab337bf5bbf4 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -5066,15 +5066,20 @@ bool sk_busy_loop(struct sock *sk, int nonblock) int (*napi_poll)(struct napi_struct *napi, int budget); void *have_poll_lock = NULL; struct napi_struct *napi; + unsigned int napi_id; int rc; restart: + napi_id = READ_ONCE(sk->sk_napi_id); + if (napi_id < MIN_NAPI_ID) + return 0; + rc = false; napi_poll = NULL; rcu_read_lock(); - napi = napi_by_id(sk->sk_napi_id); + napi = napi_by_id(napi_id); if (!napi) goto out; @@ -5143,10 +5148,10 @@ static void napi_hash_add(struct napi_struct *napi) spin_lock(&napi_hash_lock); - /* 0..NR_CPUS+1 range is reserved for sender_cpu use */ + /* 0..NR_CPUS range is reserved for sender_cpu use */ do { - if (unlikely(++napi_gen_id < NR_CPUS + 1)) - napi_gen_id = NR_CPUS + 1; + if (unlikely(++napi_gen_id < MIN_NAPI_ID)) + napi_gen_id = MIN_NAPI_ID; } while (napi_by_id(napi_gen_id)); napi->napi_id = napi_gen_id; |