[PATCH 11/19] staging: lustre: remove back_to_sleep()

NeilBrown
2018-01-08T03:30:30Z

When 'back_to_sleep()' is passed as the 'timeout' function,
the effect is to wait indefinitely for the event, polling
once after the timeout.
If LWI_ON_SIGNAL_NOOP is given, then after the timeout
we allow fatal signals to interrupt the wait.

Make this more obvious in both places "back_to_sleep()" is
used but using two explicit sleeps.

The code in ptlrpcd_add_req() looks odd - why not just have one
wait_event_idle()? However I believe this is a faithful
transformation of the existing code.

Signed-off-by: NeilBrown <neilb@suse.com>
---
drivers/staging/lustre/lustre/include/lustre_lib.h | 4 ----
drivers/staging/lustre/lustre/ptlrpc/import.c | 11 ++++++-----
drivers/staging/lustre/lustre/ptlrpc/ptlrpcd.c | 9 +++++----
3 files changed, 11 insertions(+), 13 deletions(-)

diff --git a/drivers/staging/lustre/lustre/include/lustre_lib.h b/drivers/staging/lustre/lustre/include/lustre_lib.h
index b2a64d0e682c..1939e959b92a 100644
--- a/drivers/staging/lustre/lustre/include/lustre_lib.h
+++ b/drivers/staging/lustre/lustre/include/lustre_lib.h
@@ -140,10 +140,6 @@ void target_send_reply(struct ptlrpc_request *req, int rc, int fail_id);
* XXX nikita: some ptlrpc daemon threads have races of that sort.
*
*/
-static inline int back_to_sleep(void *arg)
-{
- return 0;
-}

#define LWI_ON_SIGNAL_NOOP ((void (*)(void *))(-1))

diff --git a/drivers/staging/lustre/lustre/ptlrpc/import.c b/drivers/staging/lustre/lustre/ptlrpc/import.c
index 5d62c9de27eb..faf0f606f013 100644
--- a/drivers/staging/lustre/lustre/ptlrpc/import.c
+++ b/drivers/staging/lustre/lustre/ptlrpc/import.c
@@ -1496,7 +1496,6 @@ int ptlrpc_disconnect_import(struct obd_import *imp, int noclose)
}

if (ptlrpc_import_in_recovery(imp)) {
- struct l_wait_info lwi;
long timeout;

if (AT_OFF) {
@@ -1510,10 +1509,12 @@ int ptlrpc_disconnect_import(struct obd_import *imp, int noclose)
timeout = at_get(&imp->imp_at.iat_service_estimate[idx]) * HZ;
}

- lwi = LWI_TIMEOUT_INTR(cfs_timeout_cap(timeout),
- back_to_sleep, LWI_ON_SIGNAL_NOOP, NULL);
- rc = l_wait_event(imp->imp_recovery_waitq,
- !ptlrpc_import_in_recovery(imp), &lwi);
+ if (wait_event_idle_timeout(imp->imp_recovery_waitq,
+ !ptlrpc_import_in_recovery(imp),
+ cfs_timeout_cap(timeout)) == 0)
+ l_wait_event_abortable(
+ imp->imp_recovery_waitq,
+ !ptlrpc_import_in_recovery(imp));
}

spin_lock(&imp->imp_lock);
diff --git a/drivers/staging/lustre/lustre/ptlrpc/ptlrpcd.c b/drivers/staging/lustre/lustre/ptlrpc/ptlrpcd.c
index dad2f9290f70..437b4b2a9072 100644
--- a/drivers/staging/lustre/lustre/ptlrpc/ptlrpcd.c
+++ b/drivers/staging/lustre/lustre/ptlrpc/ptlrpcd.c
@@ -230,12 +230,13 @@ void ptlrpcd_add_req(struct ptlrpc_request *req)

spin_lock(&req->rq_lock);
if (req->rq_invalid_rqset) {
- struct l_wait_info lwi = LWI_TIMEOUT(5 * HZ,
- back_to_sleep, NULL);
-
req->rq_invalid_rqset = 0;
spin_unlock(&req->rq_lock);
- l_wait_event(req->rq_set_waitq, !req->rq_set, &lwi);
+ if (wait_event_idle_timeout(req->rq_set_waitq,
+ !req->rq_set,
+ 5 * HZ) == 0)
+ wait_event_idle(req->rq_set_waitq,
+ !req->rq_set);
} else if (req->rq_set) {
/* If we have a valid "rq_set", just reuse it to avoid double
* linked.