[PATCH 03/14] staging/lustre: conflicting PW & PR extent locks on a client

From: Oleg Drokin
Date: Wed Nov 02 2016 - 21:26:35 EST


From: Andriy Skulysh <andriy.skulysh@xxxxxxxxxxx>

PW lock isn't replayed once a lock is marked
LDLM_FL_CANCELING and glimpse lock doesn't wait for
conflicting locks on the client. So the server will
grant a PR lock in response to the glimpse lock request,
which conflicts with the PW lock in LDLM_FL_CANCELING
state on the client.

Lock in LDLM_FL_CANCELING state may still have pending IO,
so it should be replayed until LDLM_FL_BL_DONE is set to
avoid granted conflicting lock by a server.

Seagate-bug-id: MRP-3311
Signed-off-by: Andriy Skulysh <andriy.skulysh@xxxxxxxxxxx>
Reviewed-on: http://review.whamcloud.com/20345
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-8175
Reviewed-by: Jinshan Xiong <jinshan.xiong@xxxxxxxxx>
Signed-off-by: Oleg Drokin <green@xxxxxxxxxxxxxx>
---
drivers/staging/lustre/lustre/include/obd_support.h | 3 +++
drivers/staging/lustre/lustre/ldlm/ldlm_extent.c | 20 ++++++++++++++++++++
drivers/staging/lustre/lustre/ldlm/ldlm_request.c | 4 ++--
drivers/staging/lustre/lustre/osc/osc_request.c | 1 +
4 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/lustre/lustre/include/obd_support.h b/drivers/staging/lustre/lustre/include/obd_support.h
index 7f3f8cd..aaedec7 100644
--- a/drivers/staging/lustre/lustre/include/obd_support.h
+++ b/drivers/staging/lustre/lustre/include/obd_support.h
@@ -321,6 +321,8 @@ extern char obd_jobid_var[];
#define OBD_FAIL_LDLM_CP_CB_WAIT4 0x322
#define OBD_FAIL_LDLM_CP_CB_WAIT5 0x323

+#define OBD_FAIL_LDLM_GRANT_CHECK 0x32a
+
/* LOCKLESS IO */
#define OBD_FAIL_LDLM_SET_CONTENTION 0x385

@@ -343,6 +345,7 @@ extern char obd_jobid_var[];
#define OBD_FAIL_OSC_CP_ENQ_RACE 0x410
#define OBD_FAIL_OSC_NO_GRANT 0x411
#define OBD_FAIL_OSC_DELAY_SETTIME 0x412
+#define OBD_FAIL_OSC_DELAY_IO 0x414

#define OBD_FAIL_PTLRPC 0x500
#define OBD_FAIL_PTLRPC_ACK 0x501
diff --git a/drivers/staging/lustre/lustre/ldlm/ldlm_extent.c b/drivers/staging/lustre/lustre/ldlm/ldlm_extent.c
index ecf472e..a7b34e4 100644
--- a/drivers/staging/lustre/lustre/ldlm/ldlm_extent.c
+++ b/drivers/staging/lustre/lustre/ldlm/ldlm_extent.c
@@ -193,6 +193,26 @@ void ldlm_extent_add_lock(struct ldlm_resource *res,
* add the locks into grant list, for debug purpose, ..
*/
ldlm_resource_add_lock(res, &res->lr_granted, lock);
+
+ if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_GRANT_CHECK)) {
+ struct ldlm_lock *lck;
+
+ list_for_each_entry_reverse(lck, &res->lr_granted,
+ l_res_link) {
+ if (lck == lock)
+ continue;
+ if (lockmode_compat(lck->l_granted_mode,
+ lock->l_granted_mode))
+ continue;
+ if (ldlm_extent_overlap(&lck->l_req_extent,
+ &lock->l_req_extent)) {
+ CDEBUG(D_ERROR, "granting conflicting lock %p %p\n",
+ lck, lock);
+ ldlm_resource_dump(D_ERROR, res);
+ LBUG();
+ }
+ }
+ }
}

/** Remove cancelled lock from resource interval tree. */
diff --git a/drivers/staging/lustre/lustre/ldlm/ldlm_request.c b/drivers/staging/lustre/lustre/ldlm/ldlm_request.c
index 43856ff..6e704c7 100644
--- a/drivers/staging/lustre/lustre/ldlm/ldlm_request.c
+++ b/drivers/staging/lustre/lustre/ldlm/ldlm_request.c
@@ -1846,7 +1846,7 @@ static int ldlm_chain_lock_for_replay(struct ldlm_lock *lock, void *closure)
* bug 17614: locks being actively cancelled. Get a reference
* on a lock so that it does not disappear under us (e.g. due to cancel)
*/
- if (!(lock->l_flags & (LDLM_FL_FAILED | LDLM_FL_CANCELING))) {
+ if (!(lock->l_flags & (LDLM_FL_FAILED | LDLM_FL_BL_DONE))) {
list_add(&lock->l_pending_chain, list);
LDLM_LOCK_GET(lock);
}
@@ -1915,7 +1915,7 @@ static int replay_one_lock(struct obd_import *imp, struct ldlm_lock *lock)
int flags;

/* Bug 11974: Do not replay a lock which is actively being canceled */
- if (ldlm_is_canceling(lock)) {
+ if (ldlm_is_bl_done(lock)) {
LDLM_DEBUG(lock, "Not replaying canceled lock:");
return 0;
}
diff --git a/drivers/staging/lustre/lustre/osc/osc_request.c b/drivers/staging/lustre/lustre/osc/osc_request.c
index 091558e..8023561 100644
--- a/drivers/staging/lustre/lustre/osc/osc_request.c
+++ b/drivers/staging/lustre/lustre/osc/osc_request.c
@@ -1823,6 +1823,7 @@ int osc_build_rpc(const struct lu_env *env, struct client_obd *cli,
DEBUG_REQ(D_INODE, req, "%d pages, aa %p. now %ur/%dw in flight",
page_count, aa, cli->cl_r_in_flight,
cli->cl_w_in_flight);
+ OBD_FAIL_TIMEOUT(OBD_FAIL_OSC_DELAY_IO, cfs_fail_val);

ptlrpcd_add_req(req);
rc = 0;
--
2.7.4