LU-5010 llite: disable readahead optimization

[fs/lustre-release.git] / lustre / llite / rw.c

diff --git a/lustre/llite/rw.c b/lustre/llite/rw.c
index ef26a13..355d07e 100644 (file)
--- a/lustre/llite/rw.c
+++ b/lustre/llite/rw.c
@@ -332,8 +332,11 @@ static int cl_read_ahead_page(const struct lu_env *env, struct cl_io *io,
        if (!cp->cpg_defer_uptodate && !PageUptodate(vmpage)) {
                CDEBUG(D_READA, "page index %lu, max_index: %lu\n",
                       ccc_index(cp), *max_index);
-               if (*max_index == 0 || ccc_index(cp) > *max_index)
-                       rc = cl_page_is_under_lock(env, io, page, max_index);
+               /* Disable the optimization on prefetching maximum readahead
+                * index because there is a race with lock cancellation. This
+                * optimization will be revived later.
+                * if (*max_index == 0 || ccc_index(cp) > *max_index) */
+               rc = cl_page_is_under_lock(env, io, page, max_index);
                if (rc == 0) {
                        cp->cpg_defer_uptodate = 1;
                        cp->cpg_ra_used = 0;