nfsd: document callback_wq serialization of callback code

The callback code relies on the fact that much of it is only ever called
from the ordered workqueue callback_wq, and this is worth documenting.

Reported-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This commit is contained in:
J. Bruce Fields 2019-10-29 16:02:18 -04:00
parent 20428a8047
commit cc1ce2f13e

View File

@ -1243,6 +1243,12 @@ static struct nfsd4_conn * __nfsd4_find_backchannel(struct nfs4_client *clp)
return NULL;
}
/*
* Note there isn't a lot of locking in this code; instead we depend on
* the fact that it is run from the callback_wq, which won't run two
* work items at once. So, for example, callback_wq handles all access
* of cl_cb_client and all calls to rpc_create or rpc_shutdown_client.
*/
static void nfsd4_process_cb_update(struct nfsd4_callback *cb)
{
struct nfs4_cb_conn conn;