lockd: define host_for_each{_safe} macros

We've got a lot of loops like this, and I find them a little easier to
read with the macros.  More such loops are coming.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
[ cel: Forward-ported to 2.6.37 ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 55 insertions, 52 deletions

diff --git a/fs/lockd/host.c b/fs/lockd/host.c
index ed0c59fe23ce..cada3a12d557 100644
--- a/fs/lockd/host.c
+++ b/fs/lockd/host.c
@@ -26,6 +26,18 @@
 #define NLM_HOST_COLLECT        (120 * HZ)
 
 static struct hlist_head        nlm_hosts[NLM_HOST_NRHASH];
+
+#define for_each_host(host, pos, chain, table) \
+        for ((chain) = (table); \
+             (chain) < (table) + NLM_HOST_NRHASH; ++(chain)) \
+                hlist_for_each_entry((host), (pos), (chain), h_hash)
+
+#define for_each_host_safe(host, pos, next, chain, table) \
+        for ((chain) = (table); \
+             (chain) < (table) + NLM_HOST_NRHASH; ++(chain)) \
+                hlist_for_each_entry_safe((host), (pos), (next), \
+                                                (chain), h_hash)
+
 static unsigned long            next_gc;
 static int                      nrhosts;
 static DEFINE_MUTEX(nlm_host_mutex);
@@ -453,28 +465,26 @@ void nlm_host_rebooted(const struct nlm_reboot *info)
          * To avoid processing a host several times, we match the nsmstate.
          */
 again:  mutex_lock(&nlm_host_mutex);
-        for (chain = nlm_hosts; chain < nlm_hosts + NLM_HOST_NRHASH; ++chain) {
-                hlist_for_each_entry(host, pos, chain, h_hash) {
-                        if (host->h_nsmhandle == nsm
-                         && host->h_nsmstate != info->state) {
-                                host->h_nsmstate = info->state;
-                                host->h_state++;
-
-                                nlm_get_host(host);
-                                mutex_unlock(&nlm_host_mutex);
-
-                                if (host->h_server) {
-                                        /* We're server for this guy, just ditch
-                                         * all the locks he held. */
-                                        nlmsvc_free_host_resources(host);
-                                } else {
-                                        /* He's the server, initiate lock recovery. */
-                                        nlmclnt_recovery(host);
-                                }
-
-                                nlm_release_host(host);
-                                goto again;
+        for_each_host(host, pos, chain, nlm_hosts) {
+                if (host->h_nsmhandle == nsm
+                 && host->h_nsmstate != info->state) {
+                        host->h_nsmstate = info->state;
+                        host->h_state++;
+
+                        nlm_get_host(host);
+                        mutex_unlock(&nlm_host_mutex);
+
+                        if (host->h_server) {
+                                /* We're server for this guy, just ditch
+                                 * all the locks he held. */
+                                nlmsvc_free_host_resources(host);
+                        } else {
+                                /* He's the server, initiate lock recovery. */
+                                nlmclnt_recovery(host);
                         }
+
+                        nlm_release_host(host);
+                        goto again;
                 }
         }
         mutex_unlock(&nlm_host_mutex);
@@ -497,13 +507,11 @@ nlm_shutdown_hosts(void)
 
         /* First, make all hosts eligible for gc */
         dprintk("lockd: nuking all hosts...\n");
-        for (chain = nlm_hosts; chain < nlm_hosts + NLM_HOST_NRHASH; ++chain) {
-                hlist_for_each_entry(host, pos, chain, h_hash) {
-                        host->h_expires = jiffies - 1;
-                        if (host->h_rpcclnt) {
-                                rpc_shutdown_client(host->h_rpcclnt);
-                                host->h_rpcclnt = NULL;
-                        }
+        for_each_host(host, pos, chain, nlm_hosts) {
+                host->h_expires = jiffies - 1;
+                if (host->h_rpcclnt) {
+                        rpc_shutdown_client(host->h_rpcclnt);
+                        host->h_rpcclnt = NULL;
                 }
         }
 
@@ -515,12 +523,10 @@ nlm_shutdown_hosts(void)
         if (nrhosts) {
                 printk(KERN_WARNING "lockd: couldn't shutdown host module!\n");
                 dprintk("lockd: %d hosts left:\n", nrhosts);
-                for (chain = nlm_hosts; chain < nlm_hosts + NLM_HOST_NRHASH; ++chain) {
-                        hlist_for_each_entry(host, pos, chain, h_hash) {
-                                dprintk("       %s (cnt %d use %d exp %ld)\n",
-                                        host->h_name, atomic_read(&host->h_count),
-                                        host->h_inuse, host->h_expires);
-                        }
+                for_each_host(host, pos, chain, nlm_hosts) {
+                        dprintk("       %s (cnt %d use %d exp %ld)\n",
+                                host->h_name, atomic_read(&host->h_count),
+                                host->h_inuse, host->h_expires);
                 }
         }
 }
@@ -538,29 +544,26 @@ nlm_gc_hosts(void)
         struct nlm_host *host;
 
         dprintk("lockd: host garbage collection\n");
-        for (chain = nlm_hosts; chain < nlm_hosts + NLM_HOST_NRHASH; ++chain) {
-                hlist_for_each_entry(host, pos, chain, h_hash)
-                        host->h_inuse = 0;
-        }
+        for_each_host(host, pos, chain, nlm_hosts)
+                host->h_inuse = 0;
 
         /* Mark all hosts that hold locks, blocks or shares */
         nlmsvc_mark_resources();
 
-        for (chain = nlm_hosts; chain < nlm_hosts + NLM_HOST_NRHASH; ++chain) {
-                hlist_for_each_entry_safe(host, pos, next, chain, h_hash) {
-                        if (atomic_read(&host->h_count) || host->h_inuse
-                         || time_before(jiffies, host->h_expires)) {
-                                dprintk("nlm_gc_hosts skipping %s (cnt %d use %d exp %ld)\n",
-                                        host->h_name, atomic_read(&host->h_count),
-                                        host->h_inuse, host->h_expires);
-                                continue;
-                        }
-                        dprintk("lockd: delete host %s\n", host->h_name);
-                        hlist_del_init(&host->h_hash);
-
-                        nlm_destroy_host(host);
-                        nrhosts--;
+        for_each_host_safe(host, pos, next, chain, nlm_hosts) {
+                if (atomic_read(&host->h_count) || host->h_inuse
+                 || time_before(jiffies, host->h_expires)) {
+                        dprintk("nlm_gc_hosts skipping %s "
+                                "(cnt %d use %d exp %ld)\n",
+                                host->h_name, atomic_read(&host->h_count),
+                                host->h_inuse, host->h_expires);
+                        continue;
                 }
+                dprintk("lockd: delete host %s\n", host->h_name);
+                hlist_del_init(&host->h_hash);
+
+                nlm_destroy_host(host);
+                nrhosts--;
         }
 
         next_gc = jiffies + NLM_HOST_COLLECT;