[RFC PATCH v4 7/7] x86/unwind/orc: remove run-time ORC unwind tables sort

From: Shile Zhang <shile.zhang@linux.alibaba.com>
To: Peter Zijlstra <peterz@infradead.org>,
	Josh Poimboeuf <jpoimboe@redhat.com>,
	Masahiro Yamada <yamada.masahiro@socionext.com>,
	Michal Marek <michal.lkml@markovi.net>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	x86@kernel.org
Cc: "H . Peter Anvin" <hpa@zytor.com>,
	linux-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org,
	Shile Zhang <shile.zhang@linux.alibaba.com>
Subject: [RFC PATCH v4 7/7] x86/unwind/orc: remove run-time ORC unwind tables sort
Date: Sat, 16 Nov 2019 00:45:39 +0800	[thread overview]
Message-ID: <20191115164539.57930-8-shile.zhang@linux.alibaba.com> (raw)
In-Reply-To: <20191115164539.57930-1-shile.zhang@linux.alibaba.com>

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@linux.alibaba.com>
---
 arch/x86/kernel/unwind_orc.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c
index 332ae6530fa8..280da6fa9922 100644
--- a/arch/x86/kernel/unwind_orc.c
+++ b/arch/x86/kernel/unwind_orc.c
@@ -273,9 +273,11 @@ 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 by sorttable tool at build time.
+	 * Its ready for binary search now.
+	 */
 
 	/* Initialize the fast lookup table: */
 	lookup_num_blocks = orc_lookup_end - orc_lookup;
-- 
2.24.0.rc2

