LU-13783 libcfs: don't lookup symbol when not needed

Linux 5.8 and later do not export kallsyms_lookup_name() so we need to
remove dependence on it.
Looking up radix_tree_node_cachep is not needed in these kernels,
or any kernel were HAVE_XARRAY_SUPPORT is defined.
So avoid the lookup in those cases.

Signed-off-by: Mr NeilBrown <neilb@suse.de>
Change-Id: Ia61fe9a025653985b7dcf67b1234d32667719956
Reviewed-on: https://review.whamcloud.com/40825
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Aurelien Degremont <degremoa@amazon.com>

diff --git a/libcfs/libcfs/linux/linux-prim.c b/libcfs/libcfs/linux/linux-prim.c
index 5609c52..7fe3df3 100644 (file)
--- a/libcfs/libcfs/linux/linux-prim.c
+++ b/libcfs/libcfs/linux/linux-prim.c
@@ -113,7 +113,9 @@ int cfs_apply_workqueue_attrs(struct workqueue_struct *wq,
 }
 EXPORT_SYMBOL_GPL(cfs_apply_workqueue_attrs);
 
+#ifndef HAVE_XARRAY_SUPPORT
 struct kmem_cache (*radix_tree_node_cachep);
+#endif
 
 void __init cfs_arch_init(void)
 {
@@ -122,8 +124,10 @@ void __init cfs_arch_init(void)
 #endif
        cfs_apply_workqueue_attrs_t =
                (void *)kallsyms_lookup_name("apply_workqueue_attrs");
+#ifndef HAVE_XARRAY_SUPPORT
        radix_tree_node_cachep =
                (void *)kallsyms_lookup_name("radix_tree_node_cachep");
+#endif
 }
 
 int cfs_kernel_write(struct file *filp, const void *buf, size_t count,