From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932788AbXJQK51 (ORCPT ); Wed, 17 Oct 2007 06:57:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759248AbXJQK5U (ORCPT ); Wed, 17 Oct 2007 06:57:20 -0400 Received: from ozlabs.org ([203.10.76.45]:37453 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759090AbXJQK5T (ORCPT ); Wed, 17 Oct 2007 06:57:19 -0400 From: Rusty Russell To: Linus Torvalds Subject: [PATCH 5/5] Introduce "used_vectors" bitmap which can be used to reserve vectors. Date: Wed, 17 Oct 2007 20:56:04 +1000 User-Agent: KMail/1.9.6 (enterprise 0.20070907.709405) Cc: Andrew Morton , Ingo Molnar , linux-kernel@vger.kernel.org References: <200710172046.55454.rusty@rustcorp.com.au> <200710172052.47230.rusty@rustcorp.com.au> <200710172054.45652.rusty@rustcorp.com.au> In-Reply-To: <200710172054.45652.rusty@rustcorp.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200710172056.05123.rusty@rustcorp.com.au> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org This simplifies the io_apic.c __assign_irq_vector() logic and removes the explicit SYSCALL_VECTOR check, and also allows for vectors to be reserved by other mechanisms (ie. lguest). Signed-off-by: Rusty Russell Signed-off-by: Andi Kleen --- arch/x86/kernel/i8259_32.c | 3 ++- arch/x86/kernel/io_apic_32.c | 13 ++++++++----- arch/x86/kernel/traps_32.c | 10 ++++++++++ include/asm-x86/irq_32.h | 3 +++ 4 files changed, 23 insertions(+), 6 deletions(-) =================================================================== --- a/arch/x86/kernel/i8259_32.c +++ b/arch/x86/kernel/i8259_32.c @@ -400,7 +400,8 @@ void __init native_init_IRQ(void) int vector = FIRST_EXTERNAL_VECTOR + i; if (i >= NR_IRQS) break; - if (vector != SYSCALL_VECTOR) + /* SYSCALL_VECTOR was reserved in trap_init. */ + if (!test_bit(vector, used_vectors)) set_intr_gate(vector, interrupt[i]); } =================================================================== --- a/arch/x86/kernel/io_apic_32.c +++ b/arch/x86/kernel/io_apic_32.c @@ -1198,7 +1198,7 @@ static int __assign_irq_vector(int irq) static int __assign_irq_vector(int irq) { static int current_vector = FIRST_DEVICE_VECTOR, current_offset = 0; - int vector, offset, i; + int vector, offset; BUG_ON((unsigned)irq >= NR_IRQ_VECTORS); @@ -1215,11 +1215,8 @@ next: } if (vector == current_vector) return -ENOSPC; - if (vector == SYSCALL_VECTOR) + if (test_and_set_bit(vector, used_vectors)) goto next; - for (i = 0; i < NR_IRQ_VECTORS; i++) - if (irq_vector[i] == vector) - goto next; current_vector = vector; current_offset = offset; @@ -2290,6 +2287,12 @@ static inline void __init check_timer(vo void __init setup_IO_APIC(void) { + int i; + + /* Reserve all the system vectors. */ + for (i = FIRST_SYSTEM_VECTOR; i < NR_VECTORS; i++) + set_bit(i, used_vectors); + enable_IO_APIC(); if (acpi_ioapic) =================================================================== --- a/arch/x86/kernel/traps_32.c +++ b/arch/x86/kernel/traps_32.c @@ -64,6 +64,9 @@ #include "mach_traps.h" int panic_on_unrecovered_nmi; + +DECLARE_BITMAP(used_vectors, NR_VECTORS); +EXPORT_SYMBOL_GPL(used_vectors); asmlinkage int system_call(void); @@ -1156,6 +1159,8 @@ static void __init set_task_gate(unsigne void __init trap_init(void) { + int i; + #ifdef CONFIG_EISA void __iomem *p = ioremap(0x0FFFD9, 4); if (readl(p) == 'E'+('I'<<8)+('S'<<16)+('A'<<24)) { @@ -1215,6 +1220,11 @@ void __init trap_init(void) set_system_gate(SYSCALL_VECTOR,&system_call); + /* Reserve all the builtin and the syscall vector. */ + for (i = 0; i < FIRST_EXTERNAL_VECTOR; i++) + set_bit(i, used_vectors); + set_bit(SYSCALL_VECTOR, used_vectors); + /* * Should be a barrier for any external CPU state. */ =================================================================== --- a/include/asm-x86/irq_32.h +++ b/include/asm-x86/irq_32.h @@ -45,4 +45,7 @@ void init_IRQ(void); void init_IRQ(void); void __init native_init_IRQ(void); +/* Interrupt vector management */ +extern DECLARE_BITMAP(used_vectors, NR_VECTORS); + #endif /* _ASM_IRQ_H */