LU-12678 lnet: convert lpni_refcount to a kref

This refcount is used exactly like a kref.  So change it to one.
kref uses refcount_t which will warn on increment-from-zero and
similar problems (which enabled with CONFIG option), so we don't
need the LASSERT calls.

Change-Id: I857dff2c9838cb7d8f4b5f023f75f2d66119344f
Signed-off-by: Mr. NeilBrown <neilb@suse.de>
Reviewed-on: https://review.whamcloud.com/41941
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Chris Horn <chris.horn@hpe.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>

diff --git a/lnet/include/lnet/lib-lnet.h b/lnet/include/lnet/lib-lnet.h
index 176c9a2..c531055 100644 (file)
--- a/lnet/include/lnet/lib-lnet.h
+++ b/lnet/include/lnet/lib-lnet.h
@@ -375,18 +375,15 @@ lnet_peer_decref_locked(struct lnet_peer *lp)
 static inline void
 lnet_peer_ni_addref_locked(struct lnet_peer_ni *lp)
 {
-       LASSERT(atomic_read(&lp->lpni_refcount) > 0);
-       atomic_inc(&lp->lpni_refcount);
+       kref_get(&lp->lpni_kref);
 }
 
-extern void lnet_destroy_peer_ni_locked(struct lnet_peer_ni *lp);
+extern void lnet_destroy_peer_ni_locked(struct kref *ref);
 
 static inline void
 lnet_peer_ni_decref_locked(struct lnet_peer_ni *lp)
 {
-       LASSERT(atomic_read(&lp->lpni_refcount) > 0);
-       if (atomic_dec_and_test(&lp->lpni_refcount))
-               lnet_destroy_peer_ni_locked(lp);
+       kref_put(&lp->lpni_kref, lnet_destroy_peer_ni_locked);
 }
 
 static inline int

diff --git a/lnet/include/lnet/lib-types.h b/lnet/include/lnet/lib-types.h
index 4ffb27c..9f8a817 100644 (file)
--- a/lnet/include/lnet/lib-types.h
+++ b/lnet/include/lnet/lib-types.h
@@ -46,6 +46,7 @@
 #include <linux/uio.h>
 #include <linux/semaphore.h>
 #include <linux/types.h>
+#include <linux/kref.h>
 
 #include <uapi/linux/lnet/lnet-dlc.h>
 #include <uapi/linux/lnet/lnetctl.h>
@@ -580,7 +581,7 @@ struct lnet_peer_ni {
        /* peer's NID */
        lnet_nid_t              lpni_nid;
        /* # refs */
-       atomic_t                lpni_refcount;
+       struct kref             lpni_kref;
        /* health value for the peer */
        atomic_t                lpni_healthv;
        /* recovery ping mdh */

diff --git a/lnet/lnet/peer.c b/lnet/lnet/peer.c
index 04765cf..678b1f4 100644 (file)
--- a/lnet/lnet/peer.c
+++ b/lnet/lnet/peer.c
@@ -169,7 +169,7 @@ lnet_peer_ni_alloc(lnet_nid_t nid)
        INIT_LIST_HEAD(&lpni->lpni_on_remote_peer_ni_list);
        INIT_LIST_HEAD(&lpni->lpni_rtr_pref_nids);
        LNetInvalidateMDHandle(&lpni->lpni_recovery_ping_mdh);
-       atomic_set(&lpni->lpni_refcount, 1);
+       kref_init(&lpni->lpni_kref);
        lpni->lpni_sel_priority = LNET_MAX_SELECTION_PRIORITY;
 
        spin_lock_init(&lpni->lpni_lock);
@@ -1873,14 +1873,16 @@ lnet_del_peer_ni(lnet_nid_t prim_nid, lnet_nid_t nid)
 }
 
 void
-lnet_destroy_peer_ni_locked(struct lnet_peer_ni *lpni)
+lnet_destroy_peer_ni_locked(struct kref *ref)
 {
+       struct lnet_peer_ni *lpni = container_of(ref, struct lnet_peer_ni,
+                                                lpni_kref);
        struct lnet_peer_table *ptable;
        struct lnet_peer_net *lpn;
 
        CDEBUG(D_NET, "%p nid %s\n", lpni, libcfs_nid2str(lpni->lpni_nid));
 
-       LASSERT(atomic_read(&lpni->lpni_refcount) == 0);
+       LASSERT(kref_read(&lpni->lpni_kref) == 0);
        LASSERT(list_empty(&lpni->lpni_txq));
        LASSERT(lpni->lpni_txqnob == 0);
        LASSERT(list_empty(&lpni->lpni_peer_nis));
@@ -3803,7 +3805,7 @@ lnet_debug_peer(lnet_nid_t nid)
                aliveness = (lnet_is_peer_ni_alive(lp)) ? "up" : "down";
 
        CDEBUG(D_WARNING, "%-24s %4d %5s %5d %5d %5d %5d %5d %ld\n",
-              libcfs_nid2str(lp->lpni_nid), atomic_read(&lp->lpni_refcount),
+              libcfs_nid2str(lp->lpni_nid), kref_read(&lp->lpni_kref),
               aliveness, lp->lpni_net->net_tunables.lct_peer_tx_credits,
               lp->lpni_rtrcredits, lp->lpni_minrtrcredits,
               lp->lpni_txcredits, lp->lpni_mintxcredits, lp->lpni_txqnob);
@@ -3859,7 +3861,7 @@ int lnet_get_peer_ni_info(__u32 peer_index, __u64 *nid,
                                         lnet_is_peer_ni_alive(lp) ? "up" : "down");
 
                        *nid = lp->lpni_nid;
-                       *refcount = atomic_read(&lp->lpni_refcount);
+                       *refcount = kref_read(&lp->lpni_kref);
                        *ni_peer_tx_credits =
                                lp->lpni_net->net_tunables.lct_peer_tx_credits;
                        *peer_tx_credits = lp->lpni_txcredits;
@@ -3945,7 +3947,7 @@ int lnet_get_peer_info(struct lnet_ioctl_peer_cfg *cfg, void __user *bulk)
                        snprintf(lpni_info->cr_aliveness, LNET_MAX_STR_LEN,
                                lnet_is_peer_ni_alive(lpni) ? "up" : "down");
 
-               lpni_info->cr_refcount = atomic_read(&lpni->lpni_refcount);
+               lpni_info->cr_refcount = kref_read(&lpni->lpni_kref);
                lpni_info->cr_ni_peer_tx_credits = (lpni->lpni_net != NULL) ?
                        lpni->lpni_net->net_tunables.lct_peer_tx_credits : 0;
                lpni_info->cr_peer_tx_credits = lpni->lpni_txcredits;

diff --git a/lnet/lnet/router_proc.c b/lnet/lnet/router_proc.c
index c99454c..8f839d4 100644 (file)
--- a/lnet/lnet/router_proc.c
+++ b/lnet/lnet/router_proc.c
@@ -484,7 +484,7 @@ proc_lnet_peers(struct ctl_table *table, int write, void __user *buffer,
 
                if (peer != NULL) {
                        lnet_nid_t nid = peer->lpni_nid;
-                       int nrefs = atomic_read(&peer->lpni_refcount);
+                       int nrefs = kref_read(&peer->lpni_kref);
                        time64_t lastalive = -1;
                        char *aliveness = "NA";
                        int maxcr = (peer->lpni_net) ?