diff options
author | Jakub Kicinski <kuba@kernel.org> | 2025-01-23 15:16:20 -0800 |
---|---|---|
committer | Jakub Kicinski <kuba@kernel.org> | 2025-01-27 14:37:41 -0800 |
commit | 67e4bb2ced0f2d8fbd414f932daea94ba63ae4c4 (patch) | |
tree | 4d56eac815d24d22f05ee9ddf1aa34353afd954c /net/core/dev.c | |
parent | 6db9d3a536cd638e2ee17cf880e14026cec19d26 (diff) |
net: page_pool: don't try to stash the napi id
Page ppol tried to cache the NAPI ID in page pool info to avoid
having a dependency on the life cycle of the NAPI instance.
Since commit under Fixes the NAPI ID is not populated until
napi_enable() and there's a good chance that page pool is
created before NAPI gets enabled.
Protect the NAPI pointer with the existing page pool mutex,
the reading path already holds it. napi_id itself we need
to READ_ONCE(), it's protected by netdev_lock() which are
not holding in page pool.
Before this patch napi IDs were missing for mlx5:
# ./cli.py --spec netlink/specs/netdev.yaml --dump page-pool-get
[{'id': 144, 'ifindex': 2, 'inflight': 3072, 'inflight-mem': 12582912},
{'id': 143, 'ifindex': 2, 'inflight': 5568, 'inflight-mem': 22806528},
{'id': 142, 'ifindex': 2, 'inflight': 5120, 'inflight-mem': 20971520},
{'id': 141, 'ifindex': 2, 'inflight': 4992, 'inflight-mem': 20447232},
...
After:
[{'id': 144, 'ifindex': 2, 'inflight': 3072, 'inflight-mem': 12582912,
'napi-id': 565},
{'id': 143, 'ifindex': 2, 'inflight': 4224, 'inflight-mem': 17301504,
'napi-id': 525},
{'id': 142, 'ifindex': 2, 'inflight': 4288, 'inflight-mem': 17563648,
'napi-id': 524},
...
Fixes: 86e25f40aa1e ("net: napi: Add napi_config")
Reviewed-by: Mina Almasry <almasrymina@google.com>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://patch.msgid.link/20250123231620.1086401-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/core/dev.c')
-rw-r--r-- | net/core/dev.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index afa2282f2604..07b2bb1ce64f 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -6708,7 +6708,7 @@ void napi_resume_irqs(unsigned int napi_id) static void __napi_hash_add_with_id(struct napi_struct *napi, unsigned int napi_id) { - napi->napi_id = napi_id; + WRITE_ONCE(napi->napi_id, napi_id); hlist_add_head_rcu(&napi->napi_hash_node, &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]); } |