LU-13131 osc: Ensure immediate departure of sync write pages

Except for the case of direct-io and server-lock, we are
hold potentially multiple locks that are next to impossible
to find and cross reference.
So instead just send it all right away - should only
be a factor in rare cases of out of quota or close to out
of space.

Change-Id: I961cd9ba7f3266d22dfc5eff758c2f4ebbe148a4
Signed-off-by: Oleg Drokin <green@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/38453
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Wang Shilong <wshilong@ddn.com>
Reviewed-by: Bobi Jam <bobijam@hotmail.com>

diff --git a/lustre/osc/osc_cache.c b/lustre/osc/osc_cache.c
index 93cd2d6..613a056 100644 (file)
--- a/lustre/osc/osc_cache.c
+++ b/lustre/osc/osc_cache.c
@@ -1964,7 +1964,6 @@ static unsigned int get_write_extents(struct osc_object *obj,
        while (!list_empty(&obj->oo_hp_exts)) {
                ext = list_entry(obj->oo_hp_exts.next, struct osc_extent,
                                 oe_link);
-               LASSERT(ext->oe_state == OES_CACHE);
                if (!try_to_add_extent_for_io(cli, ext, &data))
                        return data.erd_page_count;
                EASSERT(ext->oe_nr_pages <= data.erd_max_pages, ext);
@@ -2643,7 +2642,21 @@ int osc_queue_sync_pages(const struct lu_env *env, const struct cl_io *io,
        /* Reuse the initial refcount for RPC, don't drop it */
        osc_extent_state_set(ext, OES_LOCK_DONE);
        if (!ext->oe_rw) { /* write */
-               list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
+               if (!ext->oe_srvlock && !ext->oe_dio) {
+                       /* The most likely case here is from lack of grants
+                        * so we are either out of quota or out of space.
+                        * Since this means we are holding locks across
+                        * potentially multi-striped IO, we must send out
+                        * everything out instantly to avoid prolonged
+                        * waits resulting in lock eviction (likely since
+                        * the extended wait in osc_cache_enter() did not
+                        * yield any additional grant due to a timeout.
+                        * LU-13131 */
+                       ext->oe_hp = 1;
+                       list_add_tail(&ext->oe_link, &obj->oo_hp_exts);
+               } else {
+                       list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
+               }
                osc_update_pending(obj, OBD_BRW_WRITE, page_count);
        } else {
                list_add_tail(&ext->oe_link, &obj->oo_reading_exts);