From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755561AbbCaRBh (ORCPT ); Tue, 31 Mar 2015 13:01:37 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48766 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752398AbbCaRB3 (ORCPT ); Tue, 31 Mar 2015 13:01:29 -0400 From: Denys Vlasenko To: Ingo Molnar Cc: Denys Vlasenko , Linus Torvalds , Steven Rostedt , Borislav Petkov , "H. Peter Anvin" , Andy Lutomirski , Oleg Nesterov , Frederic Weisbecker , Alexei Starovoitov , Will Drewry , Kees Cook , x86@kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/9] x86/asm/entry/64: simplify retint_kernel label usage, make retint_restore_args label local Date: Tue, 31 Mar 2015 19:00:05 +0200 Message-Id: <1427821211-25099-3-git-send-email-dvlasenk@redhat.com> In-Reply-To: <1427821211-25099-1-git-send-email-dvlasenk@redhat.com> References: <1427821211-25099-1-git-send-email-dvlasenk@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Get rid of #define obfuscation of retint_kernel in CONFIG_PREEMPT case by defining retint_kernel label always, not only for CONFIG_PREEMPT. Strip retint_kernel of .global-ness (ENTRY macro) - it has no users outside of this file. This looks like cosmetics, but it is not: "je LABEL" can be optimized to short jump by assember only if LABEL is not global, for global labels jump is always a near one with relocation. Convert retint_restore_args to a local numeric label, making it clearer that it is not used elsewhere in the file. Signed-off-by: Denys Vlasenko CC: Linus Torvalds CC: Steven Rostedt CC: Ingo Molnar CC: Borislav Petkov CC: "H. Peter Anvin" CC: Andy Lutomirski CC: Oleg Nesterov CC: Frederic Weisbecker CC: Alexei Starovoitov CC: Will Drewry CC: Kees Cook CC: x86@kernel.org CC: linux-kernel@vger.kernel.org --- arch/x86/kernel/entry_64.S | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index f6e37de..1879c55 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -57,10 +57,6 @@ .section .entry.text, "ax" -#ifndef CONFIG_PREEMPT -#define retint_kernel retint_restore_args -#endif - #ifdef CONFIG_PARAVIRT ENTRY(native_usergs_sysret64) swapgs @@ -741,18 +737,18 @@ opportunistic_sysret_failed: jmp restore_args /* Returning to kernel space */ +retint_kernel: #ifdef CONFIG_PREEMPT /* Interrupts are off */ /* Check if we need preemption */ -ENTRY(retint_kernel) cmpl $0,PER_CPU_VAR(__preempt_count) - jnz retint_restore_args + jnz 1f bt $9,EFLAGS(%rsp) /* interrupts were off? */ - jnc retint_restore_args + jnc 1f call preempt_schedule_irq jmp exit_intr +1: #endif -retint_restore_args: DISABLE_INTERRUPTS(CLBR_ANY) /* * The iretq could re-enable interrupts: -- 1.8.1.4