LU-12852 pfl: restrict the stripe count correctly

In function lod_get_stripe_count(), when restricting the stripe
count to the maximum xattr size, the xattr overhead should be
taken into count correctly.

Signed-off-by: Emoly Liu <emoly@whamcloud.com>
Change-Id: Ief548e47ce4d375f2e189860ccfe05d0f3c7e890
Reviewed-on: https://review.whamcloud.com/36947
Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Bobi Jam <bobijam@hotmail.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>

diff --git a/lustre/lod/lod_qos.c b/lustre/lod/lod_qos.c
index 30f1ca0..a027947 100644 (file)
--- a/lustre/lod/lod_qos.c
+++ b/lustre/lod/lod_qos.c
@@ -1837,6 +1837,7 @@ __u16 lod_get_stripe_count(struct lod_device *lod, struct lod_object *lo,
        }
 
        max_stripes = lov_mds_md_max_stripe_count(easize, LOV_MAGIC_V3);
+       max_stripes = (max_stripes == 0) ? 0 : max_stripes - 1;
 
        return (stripe_count < max_stripes) ? stripe_count : max_stripes;
 }