orangefs: sanitize handling of request list

* checking that daemon is running (to decide whether we want to limit
the timeout) should be done *after* the damn thing is included into
the list; doing that before means that if the daemon gets shut down
in between, we'll end up waiting indefinitely (== up to kill -9).

* cancels should go into the head of the queue - the sooner they
are picked, the less work daemon has to do and the sooner we get to
free the slot held by aborted operation.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

1 files changed, 18 insertions, 50 deletions

diff --git a/fs/orangefs/waitqueue.c b/fs/orangefs/waitqueue.c
index 89622717a06d..6cae77400a5b 100644
--- a/fs/orangefs/waitqueue.c
+++ b/fs/orangefs/waitqueue.c
@@ -41,37 +41,6 @@ void purge_waiting_ops(void)
         spin_unlock(&orangefs_request_list_lock);
 }
 
-static inline void
-__add_op_to_request_list(struct orangefs_kernel_op_s *op)
-{
-        spin_lock(&op->lock);
-        set_op_state_waiting(op);
-        list_add_tail(&op->list, &orangefs_request_list);
-        spin_unlock(&op->lock);
-        wake_up_interruptible(&orangefs_request_list_waitq);
-}
-
-static inline void
-add_op_to_request_list(struct orangefs_kernel_op_s *op)
-{
-        spin_lock(&orangefs_request_list_lock);
-        __add_op_to_request_list(op);
-        spin_unlock(&orangefs_request_list_lock);
-}
-
-static inline
-void add_priority_op_to_request_list(struct orangefs_kernel_op_s *op)
-{
-        spin_lock(&orangefs_request_list_lock);
-        spin_lock(&op->lock);
-        set_op_state_waiting(op);
-
-        list_add(&op->list, &orangefs_request_list);
-        spin_unlock(&orangefs_request_list_lock);
-        spin_unlock(&op->lock);
-        wake_up_interruptible(&orangefs_request_list_waitq);
-}
-
 /*
  * submits a ORANGEFS operation and waits for it to complete
  *
@@ -126,32 +95,28 @@ retry_servicing:
                 }
         }
 
-        gossip_debug(GOSSIP_WAIT_DEBUG,
-                     "%s:About to call is_daemon_in_service().\n",
-                     __func__);
-
-        if (is_daemon_in_service() < 0) {
+        /* queue up the operation */
+        spin_lock(&orangefs_request_list_lock);
+        spin_lock(&op->lock);
+        set_op_state_waiting(op);
+        if (flags & ORANGEFS_OP_PRIORITY)
+                list_add(&op->list, &orangefs_request_list);
+        else
+                list_add_tail(&op->list, &orangefs_request_list);
+        spin_unlock(&op->lock);
+        wake_up_interruptible(&orangefs_request_list_waitq);
+        if (!__is_daemon_in_service()) {
                 /*
                  * By incrementing the per-operation attempt counter, we
                  * directly go into the timeout logic while waiting for
                  * the matching downcall to be read
                  */
                 gossip_debug(GOSSIP_WAIT_DEBUG,
-                             "%s:client core is NOT in service(%d).\n",
-                             __func__,
-                             is_daemon_in_service());
-                op->attempts++;
-        }
-
-        /* queue up the operation */
-        if (flags & ORANGEFS_OP_PRIORITY) {
-                add_priority_op_to_request_list(op);
-        } else {
-                gossip_debug(GOSSIP_WAIT_DEBUG,
-                             "%s:About to call add_op_to_request_list().\n",
+                             "%s:client core is NOT in service.\n",
                              __func__);
-                add_op_to_request_list(op);
+                op->attempts++;
         }
+        spin_unlock(&orangefs_request_list_lock);
 
         if (!(flags & ORANGEFS_OP_NO_SEMAPHORE))
                 mutex_unlock(&request_mutex);
@@ -292,7 +257,10 @@ bool orangefs_cancel_op_in_progress(struct orangefs_kernel_op_s *op)
                 spin_unlock(&orangefs_request_list_lock);
                 return false;
         }
-        __add_op_to_request_list(op);
+        spin_lock(&op->lock);
+        set_op_state_waiting(op);
+        list_add(&op->list, &orangefs_request_list);
+        spin_unlock(&op->lock);
         spin_unlock(&orangefs_request_list_lock);
 
         gossip_debug(GOSSIP_UTILS_DEBUG,