On 10/1/21 1:53 PM, J. Bruce Fields wrote:
On Tue, Sep 28, 2021 at 08:56:39PM -0400, Dai Ngo wrote:
Hi Bruce,
This series of patches implement the NFSv4 Courteous Server.
Apologies, I keep meaning to get back to this and haven't yet.
I do notice I'm seeing a timeout on pynfs 4.0 test OPEN18.
It's weird, this test passes on my system:
[root@nfsvmf25 nfs4.0]# ./testserver.py $server --rundeps -v OPEN18
INIT st_setclientid.testValid : RUNNING
INIT st_setclientid.testValid : PASS
MKFILE st_open.testOpen : RUNNING
MKFILE st_open.testOpen : PASS
OPEN18 st_open.testShareConflict1 : RUNNING
OPEN18 st_open.testShareConflict1 : PASS
**************************************************
INIT st_setclientid.testValid : PASS
OPEN18 st_open.testShareConflict1 : PASS
MKFILE st_open.testOpen : PASS
**************************************************
Command line asked for 3 of 673 tests
Of those: 0 Skipped, 0 Failed, 0 Warned, 3 Passed
[root@nfsvmf25 nfs4.0]#
Do you have a network trace?
-Dai
--b.
A server which does not immediately expunge the state on lease expiration
is known as a Courteous Server. A Courteous Server continues to recognize
previously generated state tokens as valid until conflict arises between
the expired state and the requests from another client, or the server
reboots.
The v2 patch includes the following:
. add new callback, lm_expire_lock, to lock_manager_operations to
allow the lock manager to take appropriate action with conflict lock.
. handle conflicts of NFSv4 locks with NFSv3/NLM and local locks.
. expire courtesy client after 24hr if client has not reconnected.
. do not allow expired client to become courtesy client if there are
waiters for client's locks.
. modify client_info_show to show courtesy client and seconds from
last renew.
. fix a problem with NFSv4.1 server where the it keeps returning
SEQ4_STATUS_CB_PATH_DOWN in the successful SEQUENCE reply, after
the courtesy client re-connects, causing the client to keep sending
BCTS requests to server.
The v3 patch includes the following:
. modified posix_test_lock to check and resolve conflict locks
to handle NLM TEST and NFSv4 LOCKT requests.
. separate out fix for back channel stuck in SEQ4_STATUS_CB_PATH_DOWN.
The v4 patch includes:
. rework nfsd_check_courtesy to avoid dead lock of fl_lock and client_lock
by asking the laudromat thread to destroy the courtesy client.
. handle NFSv4 share reservation conflicts with courtesy client. This
includes conflicts between access mode and deny mode and vice versa.
. drop the patch for back channel stuck in SEQ4_STATUS_CB_PATH_DOWN.
The v5 patch includes:
. fix recursive locking of file_rwsem from posix_lock_file.
. retest with LOCKDEP enabled.
NOTE: I will submit pynfs tests for courteous server including tests
for share reservation conflicts in a separate patch.
