SUNRPC/NFSD: clean up get/put functions.

svc_destroy() is poorly named - it doesn't necessarily destroy the svc,
it might just reduce the ref count.
nfsd_destroy() is poorly named for the same reason.

This patch:
 - removes the refcount functionality from svc_destroy(), moving it to
   a new svc_put().  Almost all previous callers of svc_destroy() now
   call svc_put().
 - renames nfsd_destroy() to nfsd_put() and improves the code, using
   the new svc_destroy() rather than svc_put()
 - removes a few comments that explain the important for balanced
   get/put calls.  This should be obvious.

The only non-trivial part of this is that svc_destroy() would call
svc_sock_update() on a non-final decrement.  It can no longer do that,
and svc_put() isn't really a good place of it.  This call is now made
from svc_exit_thread() which seems like a good place.  This makes the
call *before* sv_nrthreads is decremented rather than after.  This
is not particularly important as the call just sets a flag which
causes sv_nrthreads set be checked later.  A subsequent patch will
improve the ordering.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

1 files changed, 5 insertions, 14 deletions

diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 4292278a9552..55a1bf0d129f 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -528,17 +528,7 @@ EXPORT_SYMBOL_GPL(svc_shutdown_net);
 void
 svc_destroy(struct svc_serv *serv)
 {
-	dprintk("svc: svc_destroy(%s, %d)\n",
-				serv->sv_program->pg_name,
-				serv->sv_nrthreads);
-
-	if (serv->sv_nrthreads) {
-		if (--(serv->sv_nrthreads) != 0) {
-			svc_sock_update_bufs(serv);
-			return;
-		}
-	} else
-		printk("svc_destroy: no threads for serv=%p!\n", serv);
+	dprintk("svc: svc_destroy(%s)\n", serv->sv_program->pg_name);
 
 	del_timer_sync(&serv->sv_temptimer);
 
@@ -892,9 +882,10 @@ svc_exit_thread(struct svc_rqst *rqstp)
 
 	svc_rqst_free(rqstp);
 
-	/* Release the server */
-	if (serv)
-		svc_destroy(serv);
+	if (!serv)
+		return;
+	svc_sock_update_bufs(serv);
+	svc_destroy(serv);
 }
 EXPORT_SYMBOL_GPL(svc_exit_thread);