LU-6010 lnet: prevent assert on LNet module unload

[fs/lustre-release.git] / lnet / lnet / module.c

diff --git a/lnet/lnet/module.c b/lnet/lnet/module.c
index 31503b7..a8f39b3 100644 (file)
--- a/lnet/lnet/module.c
+++ b/lnet/lnet/module.c
@@ -44,7 +44,7 @@ CFS_MODULE_PARM(config_on_load, "i", int, 0444,
 
 static struct mutex lnet_config_mutex;
 
-int
+static int
 lnet_configure(void *arg)
 {
        /* 'arg' only there so I can be passed to cfs_create_thread() */
@@ -53,38 +53,48 @@ lnet_configure(void *arg)
        LNET_MUTEX_LOCK(&lnet_config_mutex);
 
        if (!the_lnet.ln_niinit_self) {
+               rc = try_module_get(THIS_MODULE);
+
+               if (rc != 1)
+                       goto out;
+
                rc = LNetNIInit(LNET_PID_LUSTRE);
                if (rc >= 0) {
                        the_lnet.ln_niinit_self = 1;
                        rc = 0;
+               } else {
+                       module_put(THIS_MODULE);
                }
        }
 
+out:
        LNET_MUTEX_UNLOCK(&lnet_config_mutex);
        return rc;
 }
 
-int
+static int
 lnet_unconfigure (void)
 {
-        int   refcount;
-        
-        LNET_MUTEX_LOCK(&lnet_config_mutex);
+       int   refcount;
+
+       LNET_MUTEX_LOCK(&lnet_config_mutex);
 
-        if (the_lnet.ln_niinit_self) {
-                the_lnet.ln_niinit_self = 0;
-                LNetNIFini();
-        }
+       if (the_lnet.ln_niinit_self) {
+               the_lnet.ln_niinit_self = 0;
+               LNetNIFini();
+               module_put(THIS_MODULE);
+       }
+
+       LNET_MUTEX_LOCK(&the_lnet.ln_api_mutex);
+       refcount = the_lnet.ln_refcount;
+       LNET_MUTEX_UNLOCK(&the_lnet.ln_api_mutex);
 
-        LNET_MUTEX_LOCK(&the_lnet.ln_api_mutex);
-        refcount = the_lnet.ln_refcount;
-        LNET_MUTEX_UNLOCK(&the_lnet.ln_api_mutex);
+       LNET_MUTEX_UNLOCK(&lnet_config_mutex);
 
-        LNET_MUTEX_UNLOCK(&lnet_config_mutex);
-        return (refcount == 0) ? 0 : -EBUSY;
+       return (refcount == 0) ? 0 : -EBUSY;
 }
 
-int
+static int
 lnet_dyn_configure(struct libcfs_ioctl_hdr *hdr)
 {
        struct lnet_ioctl_config_data *conf =
@@ -109,7 +119,7 @@ lnet_dyn_configure(struct libcfs_ioctl_hdr *hdr)
        return rc;
 }
 
-int
+static int
 lnet_dyn_unconfigure(struct libcfs_ioctl_hdr *hdr)
 {
        struct lnet_ioctl_config_data *conf =
@@ -126,7 +136,7 @@ lnet_dyn_unconfigure(struct libcfs_ioctl_hdr *hdr)
        return rc;
 }
 
-int
+static int
 lnet_ioctl(unsigned int cmd, struct libcfs_ioctl_hdr *hdr)
 {
        int   rc;
@@ -163,22 +173,22 @@ lnet_ioctl(unsigned int cmd, struct libcfs_ioctl_hdr *hdr)
 
 DECLARE_IOCTL_HANDLER(lnet_ioctl_handler, lnet_ioctl);
 
-int
-init_lnet(void)
+static int
+lnet_module_init(void)
 {
-        int                  rc;
-        ENTRY;
+       int rc;
+       ENTRY;
 
        mutex_init(&lnet_config_mutex);
 
-        rc = LNetInit();
-        if (rc != 0) {
-                CERROR("LNetInit: error %d\n", rc);
-                RETURN(rc);
-        }
+       rc = lnet_init();
+       if (rc != 0) {
+               CERROR("lnet_init: error %d\n", rc);
+               RETURN(rc);
+       }
 
-        rc = libcfs_register_ioctl(&lnet_ioctl_handler);
-        LASSERT (rc == 0);
+       rc = libcfs_register_ioctl(&lnet_ioctl_handler);
+       LASSERT(rc == 0);
 
        if (config_on_load) {
                /* Have to schedule a separate thread to avoid deadlocking
@@ -186,22 +196,22 @@ init_lnet(void)
                (void) kthread_run(lnet_configure, NULL, "lnet_initd");
        }
 
-        RETURN(0);
+       RETURN(0);
 }
 
-void
-fini_lnet(void)
+static void
+lnet_module_exit(void)
 {
-        int rc;
+       int rc;
 
-        rc = libcfs_deregister_ioctl(&lnet_ioctl_handler);
-        LASSERT (rc == 0);
+       rc = libcfs_deregister_ioctl(&lnet_ioctl_handler);
+       LASSERT(rc == 0);
 
-        LNetFini();
+       lnet_fini();
 }
 
 MODULE_AUTHOR("Peter J. Braam <braam@clusterfs.com>");
 MODULE_DESCRIPTION("Portals v3.1");
 MODULE_LICENSE("GPL");
 
-cfs_module(lnet, "1.0.0", init_lnet, fini_lnet);
+cfs_module(lnet, "1.0.0", lnet_module_init, lnet_module_exit);