[RFC PATCH v2 3/3] x86/unwind/orc: remove run-time ORC unwind tables sort

From: shile . zhang
Date: Fri Nov 08 2019 - 02:11:28 EST


From: Shile Zhang <shile.zhang@xxxxxxxxxxxxxxxxx>

The orc_unwind and orc_unwind_ip tables are sorted in vmlinux link phase
at build time, just remove the run-time sort.

Signed-off-by: Shile Zhang <shile.zhang@xxxxxxxxxxxxxxxxx>
---
arch/x86/kernel/unwind_orc.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c
index 332ae6530fa8..eccb9ac1e2fe 100644
--- a/arch/x86/kernel/unwind_orc.c
+++ b/arch/x86/kernel/unwind_orc.c
@@ -273,9 +273,10 @@ void __init unwind_init(void)
return;
}

- /* Sort the .orc_unwind and .orc_unwind_ip tables: */
- sort(__start_orc_unwind_ip, num_entries, sizeof(int), orc_sort_cmp,
- orc_sort_swap);
+ /*
+ * Note, orc_unwind and orc_unwind_ip tables has been sorted in
+ * vmlinux link phase at build time. Its ready for binary search.
+ */

/* Initialize the fast lookup table: */
lookup_num_blocks = orc_lookup_end - orc_lookup;
--
2.24.0.rc2