Revert "LU-2139 osc: Track and limit "unstable" pages"

[fs/lustre-release.git] / lustre / osc / osc_cache.c

diff --git a/lustre/osc/osc_cache.c b/lustre/osc/osc_cache.c
index fc896eb..0d61628 100644 (file)
--- a/lustre/osc/osc_cache.c
+++ b/lustre/osc/osc_cache.c
@@ -27,7 +27,7 @@
  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
  *
- * Copyright (c) 2012, Intel Corporation.
+ * Copyright (c) 2012, 2013, Intel Corporation.
  *
  */
 /*
@@ -1283,8 +1283,6 @@ static int osc_completion(const struct lu_env *env, struct osc_async_page *oap,
        opg->ops_submit_time = 0;
        srvlock = oap->oap_brw_flags & OBD_BRW_SRVLOCK;
 
-       cl_page_completion(env, page, crt, rc);
-
        /* statistic */
        if (rc == 0 && srvlock) {
                struct lu_device *ld    = opg->ops_cl.cpl_obj->co_lu.lo_dev;
@@ -1303,12 +1301,9 @@ static int osc_completion(const struct lu_env *env, struct osc_async_page *oap,
         * reference counter protects page from concurrent reclaim.
         */
        lu_ref_del(&page->cp_reference, "transfer", page);
-       /*
-        * As page->cp_obj is pinned by a reference from page->cp_req, it is
-        * safe to call cl_page_put() without risking object destruction in a
-        * non-blocking context.
-        */
-       cl_page_put(env, page);
+
+       cl_page_completion(env, page, crt, rc);
+
        RETURN(0);
 }
 
@@ -1487,7 +1482,7 @@ static int ocw_granted(struct client_obd *cli, struct osc_cache_waiter *ocw)
 {
        int rc;
        client_obd_list_lock(&cli->cl_loi_list_lock);
-       rc = cfs_list_empty(&ocw->ocw_entry) || cli->cl_w_in_flight == 0;
+       rc = cfs_list_empty(&ocw->ocw_entry);
        client_obd_list_unlock(&cli->cl_loi_list_lock);
        return rc;
 }
@@ -1533,17 +1528,12 @@ static int osc_enter_cache(const struct lu_env *env, struct client_obd *cli,
        cfs_waitq_init(&ocw.ocw_waitq);
        ocw.ocw_oap   = oap;
        ocw.ocw_grant = bytes;
-       if (cli->cl_dirty > 0 || cli->cl_w_in_flight > 0) {
+       while (cli->cl_dirty > 0 || cli->cl_w_in_flight > 0) {
                cfs_list_add_tail(&ocw.ocw_entry, &cli->cl_cache_waiters);
                ocw.ocw_rc = 0;
                client_obd_list_unlock(&cli->cl_loi_list_lock);
 
-               /* First osc_io_unplug() tries to put current object
-                * on ready list, second osc_io_unplug() makes sure that
-                * dirty flush can still be triggered even if current
-                * object hasn't any dirty pages */
-               osc_io_unplug(env, cli, osc, PDL_POLICY_ROUND);
-               osc_io_unplug(env, cli, NULL, PDL_POLICY_ROUND);
+               osc_io_unplug_async(env, cli, NULL);
 
                CDEBUG(D_CACHE, "%s: sleeping for cache space @ %p for %p\n",
                       cli->cl_import->imp_obd->obd_name, &ocw, oap);
@@ -1558,20 +1548,13 @@ static int osc_enter_cache(const struct lu_env *env, struct client_obd *cli,
                        GOTO(out, rc);
                }
 
-               /* If ocw_entry isn't empty, which means it's not waked up
-                * by osc_wake_cache_waiters(), then the page must not be
-                * granted yet. */
-               if (!cfs_list_empty(&ocw.ocw_entry)) {
-                       rc = -EDQUOT;
-                       cfs_list_del_init(&ocw.ocw_entry);
-               } else {
-                       rc = ocw.ocw_rc;
-               }
+               LASSERT(cfs_list_empty(&ocw.ocw_entry));
+               rc = ocw.ocw_rc;
 
                if (rc != -EDQUOT)
                        GOTO(out, rc);
                if (osc_enter_cache_try(cli, oap, bytes, 0))
-                       rc = 0;
+                       GOTO(out, rc = 0);
        }
        EXIT;
 out:
@@ -1588,31 +1571,25 @@ void osc_wake_cache_waiters(struct client_obd *cli)
 
        ENTRY;
        cfs_list_for_each_safe(l, tmp, &cli->cl_cache_waiters) {
-               /* if we can't dirty more, we must wait until some is written */
+               ocw = cfs_list_entry(l, struct osc_cache_waiter, ocw_entry);
+               cfs_list_del_init(&ocw->ocw_entry);
+
+               ocw->ocw_rc = -EDQUOT;
+               /* we can't dirty more */
                if ((cli->cl_dirty + CFS_PAGE_SIZE > cli->cl_dirty_max) ||
                    (cfs_atomic_read(&obd_dirty_pages) + 1 >
                     obd_max_dirty_pages)) {
                        CDEBUG(D_CACHE, "no dirty room: dirty: %ld "
                               "osc max %ld, sys max %d\n", cli->cl_dirty,
                               cli->cl_dirty_max, obd_max_dirty_pages);
-                       return;
+                       goto wakeup;
                }
 
-               /* if still dirty cache but no grant wait for pending RPCs that
-                * may yet return us some grant before doing sync writes */
-               if (cli->cl_w_in_flight && cli->cl_avail_grant < CFS_PAGE_SIZE) {
-                       CDEBUG(D_CACHE, "%u BRW writes in flight, no grant\n",
-                              cli->cl_w_in_flight);
-                       return;
-               }
-
-               ocw = cfs_list_entry(l, struct osc_cache_waiter, ocw_entry);
-               cfs_list_del_init(&ocw->ocw_entry);
-
                ocw->ocw_rc = 0;
                if (!osc_enter_cache_try(cli, ocw->ocw_oap, ocw->ocw_grant, 0))
                        ocw->ocw_rc = -EDQUOT;
 
+wakeup:
                CDEBUG(D_CACHE, "wake up %p for oap %p, avail grant %ld, %d\n",
                       ocw, ocw->ocw_oap, cli->cl_avail_grant, ocw->ocw_rc);
 
@@ -2155,7 +2132,11 @@ static int osc_io_unplug0(const struct lu_env *env, struct client_obd *cli,
                has_rpcs = __osc_list_maint(cli, osc);
        if (has_rpcs) {
                if (!async) {
+                       /* disable osc_lru_shrink() temporarily to avoid
+                        * potential stack overrun problem. LU-2859 */
+                       cfs_atomic_inc(&cli->cl_lru_shrinkers);
                        osc_check_rpcs(env, cli, pol);
+                       cfs_atomic_dec(&cli->cl_lru_shrinkers);
                } else {
                        CDEBUG(D_CACHE, "Queue writeback work for client %p.\n",
                               cli);
@@ -2602,7 +2583,7 @@ int osc_queue_sync_pages(const struct lu_env *env, struct osc_object *obj,
        }
        osc_object_unlock(obj);
 
-       osc_io_unplug(env, cli, obj, PDL_POLICY_ROUND);
+       osc_io_unplug_async(env, cli, obj);
        RETURN(0);
 }